Merge "Add error propagation into Unwinder/Elf objects."
am: 19ab4580be

Change-Id: I05d8efab28d7098755d9eba21a0849e582ff8107
diff --git a/libunwindstack/ArmExidx.cpp b/libunwindstack/ArmExidx.cpp
index 6b0646f..65638ae 100644
--- a/libunwindstack/ArmExidx.cpp
+++ b/libunwindstack/ArmExidx.cpp
@@ -57,6 +57,7 @@
   uint32_t data;
   if (!elf_memory_->Read32(entry_offset + 4, &data)) {
     status_ = ARM_STATUS_READ_FAILED;
+    status_address_ = entry_offset + 4;
     return false;
   }
   if (data == 1) {
@@ -97,6 +98,7 @@
   uint32_t addr = (entry_offset + 4) + signed_data;
   if (!elf_memory_->Read32(addr, &data)) {
     status_ = ARM_STATUS_READ_FAILED;
+    status_address_ = addr;
     return false;
   }
 
@@ -128,6 +130,7 @@
     addr += 4;
     if (!elf_memory_->Read32(addr, &data)) {
       status_ = ARM_STATUS_READ_FAILED;
+      status_address_ = addr;
       return false;
     }
     num_table_words = (data >> 24) & 0xff;
@@ -145,6 +148,7 @@
   for (size_t i = 0; i < num_table_words; i++) {
     if (!elf_memory_->Read32(addr, &data)) {
       status_ = ARM_STATUS_READ_FAILED;
+      status_address_ = addr;
       return false;
     }
     data_.push_back((data >> 24) & 0xff);
@@ -216,6 +220,7 @@
     if (registers & (1 << reg)) {
       if (!process_memory_->Read32(cfa_, &(*regs_)[reg])) {
         status_ = ARM_STATUS_READ_FAILED;
+        status_address_ = cfa_;
         return false;
       }
       cfa_ += 4;
@@ -284,6 +289,7 @@
   for (size_t i = 4; i <= 4 + (byte & 0x7); i++) {
     if (!process_memory_->Read32(cfa_, &(*regs_)[i])) {
       status_ = ARM_STATUS_READ_FAILED;
+      status_address_ = cfa_;
       return false;
     }
     cfa_ += 4;
@@ -291,6 +297,7 @@
   if (byte & 0x8) {
     if (!process_memory_->Read32(cfa_, &(*regs_)[ARM_REG_R14])) {
       status_ = ARM_STATUS_READ_FAILED;
+      status_address_ = cfa_;
       return false;
     }
     cfa_ += 4;
@@ -357,6 +364,7 @@
     if (byte & (1 << reg)) {
       if (!process_memory_->Read32(cfa_, &(*regs_)[reg])) {
         status_ = ARM_STATUS_READ_FAILED;
+        status_address_ = cfa_;
         return false;
       }
       cfa_ += 4;
diff --git a/libunwindstack/ArmExidx.h b/libunwindstack/ArmExidx.h
index f4361d4..96756a0 100644
--- a/libunwindstack/ArmExidx.h
+++ b/libunwindstack/ArmExidx.h
@@ -61,6 +61,7 @@
   std::deque<uint8_t>* data() { return &data_; }
 
   ArmStatus status() { return status_; }
+  uint64_t status_address() { return status_address_; }
 
   RegsArm* regs() { return regs_; }
 
@@ -97,6 +98,7 @@
   uint32_t cfa_ = 0;
   std::deque<uint8_t> data_;
   ArmStatus status_ = ARM_STATUS_NONE;
+  uint64_t status_address_ = 0;
 
   Memory* elf_memory_;
   Memory* process_memory_;
diff --git a/libunwindstack/Check.h b/libunwindstack/Check.h
index 2d216d7..9643d76 100644
--- a/libunwindstack/Check.h
+++ b/libunwindstack/Check.h
@@ -14,8 +14,8 @@
  * limitations under the License.
  */
 
-#ifndef _LIBUNWINDSTACK_ERROR_H
-#define _LIBUNWINDSTACK_ERROR_H
+#ifndef _LIBUNWINDSTACK_CHECK_H
+#define _LIBUNWINDSTACK_CHECK_H
 
 #include <stdlib.h>
 
@@ -31,4 +31,4 @@
 
 }  // namespace unwindstack
 
-#endif  // _LIBUNWINDSTACK_ERROR_H
+#endif  // _LIBUNWINDSTACK_CHECK_H
diff --git a/libunwindstack/DwarfCfa.cpp b/libunwindstack/DwarfCfa.cpp
index b1d55ba..4fc95c7 100644
--- a/libunwindstack/DwarfCfa.cpp
+++ b/libunwindstack/DwarfCfa.cpp
@@ -23,12 +23,12 @@
 
 #include <android-base/stringprintf.h>
 
+#include <unwindstack/DwarfError.h>
 #include <unwindstack/DwarfLocation.h>
 #include <unwindstack/Log.h>
 
 #include "DwarfCfa.h"
 #include "DwarfEncoding.h"
-#include "DwarfError.h"
 #include "DwarfOp.h"
 
 namespace unwindstack {
@@ -44,7 +44,8 @@
       (*loc_regs)[entry.first] = entry.second;
     }
   }
-  last_error_ = DWARF_ERROR_NONE;
+  last_error_.code = DWARF_ERROR_NONE;
+  last_error_.address = 0;
 
   memory_->set_cur_offset(start_offset);
   uint64_t cfa_offset;
@@ -54,7 +55,8 @@
     // Read the cfa information.
     uint8_t cfa_value;
     if (!memory_->ReadBytes(&cfa_value, 1)) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_->cur_offset();
       return false;
     }
     uint8_t cfa_low = cfa_value & 0x3f;
@@ -66,7 +68,8 @@
       case 2: {
         uint64_t offset;
         if (!memory_->ReadULEB128(&offset)) {
-          last_error_ = DWARF_ERROR_MEMORY_INVALID;
+          last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+          last_error_.address = memory_->cur_offset();
           return false;
         }
         SignedType signed_offset =
@@ -78,7 +81,7 @@
       case 3: {
         if (cie_loc_regs_ == nullptr) {
           log(0, "restore while processing cie");
-          last_error_ = DWARF_ERROR_ILLEGAL_STATE;
+          last_error_.code = DWARF_ERROR_ILLEGAL_STATE;
           return false;
         }
 
@@ -93,7 +96,7 @@
       case 0: {
         const auto handle_func = DwarfCfa<AddressType>::kCallbackTable[cfa_low];
         if (handle_func == nullptr) {
-          last_error_ = DWARF_ERROR_ILLEGAL_VALUE;
+          last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
           return false;
         }
 
@@ -102,7 +105,8 @@
           if (cfa->operands[i] == DW_EH_PE_block) {
             uint64_t block_length;
             if (!memory_->ReadULEB128(&block_length)) {
-              last_error_ = DWARF_ERROR_MEMORY_INVALID;
+              last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+              last_error_.address = memory_->cur_offset();
               return false;
             }
             operands_.push_back(block_length);
@@ -111,7 +115,8 @@
           }
           uint64_t value;
           if (!memory_->ReadEncodedValue<AddressType>(cfa->operands[i], &value)) {
-            last_error_ = DWARF_ERROR_MEMORY_INVALID;
+            last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+            last_error_.address = memory_->cur_offset();
             return false;
           }
           operands_.push_back(value);
@@ -334,7 +339,7 @@
   AddressType reg = operands_[0];
   if (cie_loc_regs_ == nullptr) {
     log(0, "restore while processing cie");
-    last_error_ = DWARF_ERROR_ILLEGAL_STATE;
+    last_error_.code = DWARF_ERROR_ILLEGAL_STATE;
     return false;
   }
   auto reg_entry = cie_loc_regs_->find(reg);
@@ -396,7 +401,7 @@
   auto cfa_location = loc_regs->find(CFA_REG);
   if (cfa_location == loc_regs->end() || cfa_location->second.type != DWARF_LOCATION_REGISTER) {
     log(0, "Attempt to set new register, but cfa is not already set to a register.");
-    last_error_ = DWARF_ERROR_ILLEGAL_STATE;
+    last_error_.code = DWARF_ERROR_ILLEGAL_STATE;
     return false;
   }
 
@@ -410,7 +415,7 @@
   auto cfa_location = loc_regs->find(CFA_REG);
   if (cfa_location == loc_regs->end() || cfa_location->second.type != DWARF_LOCATION_REGISTER) {
     log(0, "Attempt to set offset, but cfa is not set to a register.");
-    last_error_ = DWARF_ERROR_ILLEGAL_STATE;
+    last_error_.code = DWARF_ERROR_ILLEGAL_STATE;
     return false;
   }
   cfa_location->second.values[1] = operands_[0];
@@ -454,7 +459,7 @@
   auto cfa_location = loc_regs->find(CFA_REG);
   if (cfa_location == loc_regs->end() || cfa_location->second.type != DWARF_LOCATION_REGISTER) {
     log(0, "Attempt to set offset, but cfa is not set to a register.");
-    last_error_ = DWARF_ERROR_ILLEGAL_STATE;
+    last_error_.code = DWARF_ERROR_ILLEGAL_STATE;
     return false;
   }
   SignedType offset = static_cast<SignedType>(operands_[0]) * fde_->cie->data_alignment_factor;
diff --git a/libunwindstack/DwarfCfa.h b/libunwindstack/DwarfCfa.h
index 62b9b7a..16c66e2 100644
--- a/libunwindstack/DwarfCfa.h
+++ b/libunwindstack/DwarfCfa.h
@@ -24,12 +24,11 @@
 #include <type_traits>
 #include <vector>
 
+#include <unwindstack/DwarfError.h>
 #include <unwindstack/DwarfLocation.h>
 #include <unwindstack/DwarfMemory.h>
 #include <unwindstack/DwarfStructs.h>
 
-#include "DwarfError.h"
-
 namespace unwindstack {
 
 // DWARF Standard home: http://dwarfstd.org/
@@ -75,7 +74,9 @@
   bool Log(uint32_t indent, uint64_t pc, uint64_t load_bias, uint64_t start_offset,
            uint64_t end_offset);
 
-  DwarfError last_error() { return last_error_; }
+  const DwarfErrorData& last_error() { return last_error_; }
+  DwarfErrorCode LastErrorCode() { return last_error_.code; }
+  uint64_t LastErrorAddress() { return last_error_.address; }
 
   AddressType cur_pc() { return cur_pc_; }
 
@@ -89,7 +90,7 @@
   bool LogInstruction(uint32_t indent, uint64_t cfa_offset, uint8_t op, uint64_t* cur_pc);
 
  private:
-  DwarfError last_error_;
+  DwarfErrorData last_error_;
   DwarfMemory* memory_;
   const DwarfFde* fde_;
 
diff --git a/libunwindstack/DwarfEhFrameWithHdr.cpp b/libunwindstack/DwarfEhFrameWithHdr.cpp
index e0f1eed..a131abe 100644
--- a/libunwindstack/DwarfEhFrameWithHdr.cpp
+++ b/libunwindstack/DwarfEhFrameWithHdr.cpp
@@ -16,12 +16,12 @@
 
 #include <stdint.h>
 
+#include <unwindstack/DwarfError.h>
 #include <unwindstack/DwarfStructs.h>
 #include <unwindstack/Memory.h>
 
 #include "Check.h"
 #include "DwarfEhFrameWithHdr.h"
-#include "DwarfError.h"
 
 namespace unwindstack {
 
@@ -36,14 +36,15 @@
 
   // Read the first four bytes all at once.
   if (!memory_.ReadBytes(data, 4)) {
-    last_error_ = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.address = memory_.cur_offset();
     return false;
   }
 
   version_ = data[0];
   if (version_ != 1) {
     // Unknown version.
-    last_error_ = DWARF_ERROR_UNSUPPORTED_VERSION;
+    last_error_.code = DWARF_ERROR_UNSUPPORTED_VERSION;
     return false;
   }
 
@@ -54,18 +55,20 @@
 
   memory_.set_pc_offset(memory_.cur_offset());
   if (!memory_.template ReadEncodedValue<AddressType>(ptr_encoding_, &ptr_offset_)) {
-    last_error_ = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.address = memory_.cur_offset();
     return false;
   }
 
   memory_.set_pc_offset(memory_.cur_offset());
   if (!memory_.template ReadEncodedValue<AddressType>(fde_count_encoding, &fde_count_)) {
-    last_error_ = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.address = memory_.cur_offset();
     return false;
   }
 
   if (fde_count_ == 0) {
-    last_error_ = DWARF_ERROR_NO_FDES;
+    last_error_.code = DWARF_ERROR_NO_FDES;
     return false;
   }
 
@@ -101,7 +104,8 @@
   uint64_t value;
   if (!memory_.template ReadEncodedValue<AddressType>(table_encoding_, &value) ||
       !memory_.template ReadEncodedValue<AddressType>(table_encoding_, &info->offset)) {
-    last_error_ = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.address = memory_.cur_offset();
     fde_info_.erase(index);
     return nullptr;
   }
@@ -147,7 +151,9 @@
 template <typename AddressType>
 bool DwarfEhFrameWithHdr<AddressType>::GetFdeOffsetSequential(uint64_t pc, uint64_t* fde_offset) {
   CHECK(fde_count_ != 0);
-  last_error_ = DWARF_ERROR_NONE;
+  last_error_.code = DWARF_ERROR_NONE;
+  last_error_.address = 0;
+
   // We can do a binary search if the pc is in the range of the elements
   // that have already been cached.
   if (!fde_info_.empty()) {
@@ -176,14 +182,16 @@
     memory_.set_pc_offset(memory_.cur_offset());
     uint64_t value;
     if (!memory_.template ReadEncodedValue<AddressType>(table_encoding_, &value)) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_.cur_offset();
       return false;
     }
 
     FdeInfo* info = &fde_info_[current];
     if (!memory_.template ReadEncodedValue<AddressType>(table_encoding_, &info->offset)) {
       fde_info_.erase(current);
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_.cur_offset();
       return false;
     }
     info->pc = value + 4;
diff --git a/libunwindstack/DwarfOp.cpp b/libunwindstack/DwarfOp.cpp
index 3b3d340..dcf04e6 100644
--- a/libunwindstack/DwarfOp.cpp
+++ b/libunwindstack/DwarfOp.cpp
@@ -22,12 +22,12 @@
 
 #include <android-base/stringprintf.h>
 
+#include <unwindstack/DwarfError.h>
 #include <unwindstack/DwarfMemory.h>
 #include <unwindstack/Log.h>
 #include <unwindstack/Memory.h>
 #include <unwindstack/Regs.h>
 
-#include "DwarfError.h"
 #include "DwarfOp.h"
 
 namespace unwindstack {
@@ -48,7 +48,7 @@
     // To protect against a branch that creates an infinite loop,
     // terminate if the number of iterations gets too high.
     if (iterations++ == 1000) {
-      last_error_ = DWARF_ERROR_TOO_MANY_ITERATIONS;
+      last_error_.code = DWARF_ERROR_TOO_MANY_ITERATIONS;
       return false;
     }
   }
@@ -57,28 +57,29 @@
 
 template <typename AddressType>
 bool DwarfOp<AddressType>::Decode(uint8_t dwarf_version) {
-  last_error_ = DWARF_ERROR_NONE;
+  last_error_.code = DWARF_ERROR_NONE;
   if (!memory_->ReadBytes(&cur_op_, 1)) {
-    last_error_ = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.address = memory_->cur_offset();
     return false;
   }
 
   const auto* op = &kCallbackTable[cur_op_];
   const auto handle_func = op->handle_func;
   if (handle_func == nullptr) {
-    last_error_ = DWARF_ERROR_ILLEGAL_VALUE;
+    last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
     return false;
   }
 
   // Check for an unsupported opcode.
   if (dwarf_version < op->supported_version) {
-    last_error_ = DWARF_ERROR_ILLEGAL_VALUE;
+    last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
     return false;
   }
 
   // Make sure that the required number of stack elements is available.
   if (stack_.size() < op->num_required_stack_values) {
-    last_error_ = DWARF_ERROR_STACK_INDEX_NOT_VALID;
+    last_error_.code = DWARF_ERROR_STACK_INDEX_NOT_VALID;
     return false;
   }
 
@@ -86,7 +87,8 @@
   for (size_t i = 0; i < op->num_operands; i++) {
     uint64_t value;
     if (!memory_->ReadEncodedValue<AddressType>(op->operands[i], &value)) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_->cur_offset();
       return false;
     }
     operands_.push_back(value);
@@ -142,7 +144,8 @@
   AddressType addr = StackPop();
   AddressType value;
   if (!regular_memory()->ReadFully(addr, &value, sizeof(value))) {
-    last_error_ = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.address = addr;
     return false;
   }
   stack_.push_front(value);
@@ -153,14 +156,15 @@
 bool DwarfOp<AddressType>::op_deref_size() {
   AddressType bytes_to_read = OperandAt(0);
   if (bytes_to_read > sizeof(AddressType) || bytes_to_read == 0) {
-    last_error_ = DWARF_ERROR_ILLEGAL_VALUE;
+    last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
     return false;
   }
   // Read the address and dereference it.
   AddressType addr = StackPop();
   AddressType value = 0;
   if (!regular_memory()->ReadFully(addr, &value, bytes_to_read)) {
-    last_error_ = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.address = addr;
     return false;
   }
   stack_.push_front(value);
@@ -198,7 +202,7 @@
 bool DwarfOp<AddressType>::op_pick() {
   AddressType index = OperandAt(0);
   if (index > StackSize()) {
-    last_error_ = DWARF_ERROR_STACK_INDEX_NOT_VALID;
+    last_error_.code = DWARF_ERROR_STACK_INDEX_NOT_VALID;
     return false;
   }
   stack_.push_front(StackAt(index));
@@ -243,7 +247,7 @@
 bool DwarfOp<AddressType>::op_div() {
   AddressType top = StackPop();
   if (top == 0) {
-    last_error_ = DWARF_ERROR_ILLEGAL_VALUE;
+    last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
     return false;
   }
   SignedType signed_divisor = static_cast<SignedType>(top);
@@ -263,7 +267,7 @@
 bool DwarfOp<AddressType>::op_mod() {
   AddressType top = StackPop();
   if (top == 0) {
-    last_error_ = DWARF_ERROR_ILLEGAL_VALUE;
+    last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
     return false;
   }
   stack_[0] %= top;
@@ -431,7 +435,7 @@
 bool DwarfOp<AddressType>::op_breg() {
   uint16_t reg = cur_op() - 0x70;
   if (reg >= regs_->total_regs()) {
-    last_error_ = DWARF_ERROR_ILLEGAL_VALUE;
+    last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
     return false;
   }
   stack_.push_front((*regs_)[reg] + OperandAt(0));
@@ -442,7 +446,7 @@
 bool DwarfOp<AddressType>::op_bregx() {
   AddressType reg = OperandAt(0);
   if (reg >= regs_->total_regs()) {
-    last_error_ = DWARF_ERROR_ILLEGAL_VALUE;
+    last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
     return false;
   }
   stack_.push_front((*regs_)[reg] + OperandAt(1));
@@ -456,7 +460,7 @@
 
 template <typename AddressType>
 bool DwarfOp<AddressType>::op_not_implemented() {
-  last_error_ = DWARF_ERROR_NOT_IMPLEMENTED;
+  last_error_.code = DWARF_ERROR_NOT_IMPLEMENTED;
   return false;
 }
 
diff --git a/libunwindstack/DwarfOp.h b/libunwindstack/DwarfOp.h
index c29bf35..40b7b23 100644
--- a/libunwindstack/DwarfOp.h
+++ b/libunwindstack/DwarfOp.h
@@ -24,8 +24,9 @@
 #include <type_traits>
 #include <vector>
 
+#include <unwindstack/DwarfError.h>
+
 #include "DwarfEncoding.h"
-#include "DwarfError.h"
 
 namespace unwindstack {
 
@@ -72,7 +73,9 @@
 
   void set_regs(RegsImpl<AddressType>* regs) { regs_ = regs; }
 
-  DwarfError last_error() { return last_error_; }
+  const DwarfErrorData& last_error() { return last_error_; }
+  DwarfErrorCode LastErrorCode() { return last_error_.code; }
+  uint64_t LastErrorAddress() { return last_error_.address; }
 
   bool is_register() { return is_register_; }
 
@@ -96,7 +99,7 @@
 
   RegsImpl<AddressType>* regs_;
   bool is_register_ = false;
-  DwarfError last_error_ = DWARF_ERROR_NONE;
+  DwarfErrorData last_error_{DWARF_ERROR_NONE, 0};
   uint8_t cur_op_;
   std::vector<AddressType> operands_;
   std::deque<AddressType> stack_;
diff --git a/libunwindstack/DwarfSection.cpp b/libunwindstack/DwarfSection.cpp
index 04a1fae..4e94f88 100644
--- a/libunwindstack/DwarfSection.cpp
+++ b/libunwindstack/DwarfSection.cpp
@@ -16,6 +16,7 @@
 
 #include <stdint.h>
 
+#include <unwindstack/DwarfError.h>
 #include <unwindstack/DwarfLocation.h>
 #include <unwindstack/DwarfMemory.h>
 #include <unwindstack/DwarfSection.h>
@@ -26,7 +27,6 @@
 
 #include "DwarfCfa.h"
 #include "DwarfEncoding.h"
-#include "DwarfError.h"
 #include "DwarfOp.h"
 
 #include "DwarfDebugFrame.h"
@@ -36,7 +36,7 @@
 
 constexpr uint64_t DEX_PC_REG = 0x20444558;
 
-DwarfSection::DwarfSection(Memory* memory) : memory_(memory), last_error_(DWARF_ERROR_NONE) {}
+DwarfSection::DwarfSection(Memory* memory) : memory_(memory) {}
 
 const DwarfFde* DwarfSection::GetFdeFromPc(uint64_t pc) {
   uint64_t fde_offset;
@@ -52,15 +52,15 @@
   if (pc < fde->pc_end) {
     return fde;
   }
-  last_error_ = DWARF_ERROR_ILLEGAL_STATE;
+  last_error_.code = DWARF_ERROR_ILLEGAL_STATE;
   return nullptr;
 }
 
 bool DwarfSection::Step(uint64_t pc, Regs* regs, Memory* process_memory, bool* finished) {
-  last_error_ = DWARF_ERROR_NONE;
+  last_error_.code = DWARF_ERROR_NONE;
   const DwarfFde* fde = GetFdeFromPc(pc);
   if (fde == nullptr || fde->cie == nullptr) {
-    last_error_ = DWARF_ERROR_ILLEGAL_STATE;
+    last_error_.code = DWARF_ERROR_ILLEGAL_STATE;
     return false;
   }
 
@@ -87,12 +87,12 @@
     return false;
   }
   if (op.StackSize() == 0) {
-    last_error_ = DWARF_ERROR_ILLEGAL_STATE;
+    last_error_.code = DWARF_ERROR_ILLEGAL_STATE;
     return false;
   }
   // We don't support an expression that evaluates to a register number.
   if (op.is_register()) {
-    last_error_ = DWARF_ERROR_NOT_IMPLEMENTED;
+    last_error_.code = DWARF_ERROR_NOT_IMPLEMENTED;
     return false;
   }
   *value = op.StackAt(0);
@@ -119,7 +119,8 @@
   switch (loc->type) {
     case DWARF_LOCATION_OFFSET:
       if (!regular_memory->ReadFully(eval_info->cfa + loc->values[0], reg_ptr, sizeof(AddressType))) {
-        last_error_ = DWARF_ERROR_MEMORY_INVALID;
+        last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+        last_error_.address = eval_info->cfa + loc->values[0];
         return false;
       }
       break;
@@ -129,7 +130,7 @@
     case DWARF_LOCATION_REGISTER: {
       uint32_t cur_reg = loc->values[0];
       if (cur_reg >= eval_info->cur_regs->total_regs()) {
-        last_error_ = DWARF_ERROR_ILLEGAL_VALUE;
+        last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
         return false;
       }
       AddressType* cur_reg_ptr = &(*eval_info->cur_regs)[cur_reg];
@@ -158,7 +159,8 @@
       }
       if (loc->type == DWARF_LOCATION_EXPRESSION) {
         if (!regular_memory->ReadFully(value, reg_ptr, sizeof(AddressType))) {
-          last_error_ = DWARF_ERROR_MEMORY_INVALID;
+          last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+          last_error_.address = value;
           return false;
         }
       } else {
@@ -183,14 +185,14 @@
                                          bool* finished) {
   RegsImpl<AddressType>* cur_regs = reinterpret_cast<RegsImpl<AddressType>*>(regs);
   if (cie->return_address_register >= cur_regs->total_regs()) {
-    last_error_ = DWARF_ERROR_ILLEGAL_VALUE;
+    last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
     return false;
   }
 
   // Get the cfa value;
   auto cfa_entry = loc_regs.find(CFA_REG);
   if (cfa_entry == loc_regs.end()) {
-    last_error_ = DWARF_ERROR_CFA_NOT_DEFINED;
+    last_error_.code = DWARF_ERROR_CFA_NOT_DEFINED;
     return false;
   }
 
@@ -206,7 +208,7 @@
   switch (loc->type) {
     case DWARF_LOCATION_REGISTER:
       if (loc->values[0] >= cur_regs->total_regs()) {
-        last_error_ = DWARF_ERROR_ILLEGAL_VALUE;
+        last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
         return false;
       }
       // If the stack pointer register is the CFA, and the stack
@@ -227,7 +229,8 @@
       }
       if (loc->type == DWARF_LOCATION_EXPRESSION) {
         if (!regular_memory->ReadFully(value, &eval_info.cfa, sizeof(AddressType))) {
-          last_error_ = DWARF_ERROR_MEMORY_INVALID;
+          last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+          last_error_.address = value;
           return false;
         }
       } else {
@@ -236,7 +239,7 @@
       break;
     }
     default:
-      last_error_ = DWARF_ERROR_ILLEGAL_VALUE;
+      last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
       return false;
   }
 
@@ -305,7 +308,8 @@
 bool DwarfSectionImpl<AddressType>::FillInCie(DwarfCie* cie) {
   uint32_t length32;
   if (!memory_.ReadBytes(&length32, sizeof(length32))) {
-    last_error_ = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.address = memory_.cur_offset();
     return false;
   }
   // Set the default for the lsda encoding.
@@ -315,7 +319,8 @@
     // 64 bit Cie
     uint64_t length64;
     if (!memory_.ReadBytes(&length64, sizeof(length64))) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_.cur_offset();
       return false;
     }
 
@@ -324,12 +329,13 @@
 
     uint64_t cie_id;
     if (!memory_.ReadBytes(&cie_id, sizeof(cie_id))) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_.cur_offset();
       return false;
     }
     if (cie_id != cie64_value_) {
       // This is not a Cie, something has gone horribly wrong.
-      last_error_ = DWARF_ERROR_ILLEGAL_VALUE;
+      last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
       return false;
     }
   } else {
@@ -339,24 +345,26 @@
 
     uint32_t cie_id;
     if (!memory_.ReadBytes(&cie_id, sizeof(cie_id))) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_.cur_offset();
       return false;
     }
     if (cie_id != cie32_value_) {
       // This is not a Cie, something has gone horribly wrong.
-      last_error_ = DWARF_ERROR_ILLEGAL_VALUE;
+      last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
       return false;
     }
   }
 
   if (!memory_.ReadBytes(&cie->version, sizeof(cie->version))) {
-    last_error_ = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.address = memory_.cur_offset();
     return false;
   }
 
   if (cie->version != 1 && cie->version != 3 && cie->version != 4) {
     // Unrecognized version.
-    last_error_ = DWARF_ERROR_UNSUPPORTED_VERSION;
+    last_error_.code = DWARF_ERROR_UNSUPPORTED_VERSION;
     return false;
   }
 
@@ -364,7 +372,8 @@
   char aug_value;
   do {
     if (!memory_.ReadBytes(&aug_value, 1)) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_.cur_offset();
       return false;
     }
     cie->augmentation_string.push_back(aug_value);
@@ -376,20 +385,23 @@
 
     // Segment Size
     if (!memory_.ReadBytes(&cie->segment_size, 1)) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_.cur_offset();
       return false;
     }
   }
 
   // Code Alignment Factor
   if (!memory_.ReadULEB128(&cie->code_alignment_factor)) {
-    last_error_ = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.address = memory_.cur_offset();
     return false;
   }
 
   // Data Alignment Factor
   if (!memory_.ReadSLEB128(&cie->data_alignment_factor)) {
-    last_error_ = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.address = memory_.cur_offset();
     return false;
   }
 
@@ -397,12 +409,14 @@
     // Return Address is a single byte.
     uint8_t return_address_register;
     if (!memory_.ReadBytes(&return_address_register, 1)) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_.cur_offset();
       return false;
     }
     cie->return_address_register = return_address_register;
   } else if (!memory_.ReadULEB128(&cie->return_address_register)) {
-    last_error_ = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.address = memory_.cur_offset();
     return false;
   }
 
@@ -413,7 +427,8 @@
 
   uint64_t aug_length;
   if (!memory_.ReadULEB128(&aug_length)) {
-    last_error_ = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.address = memory_.cur_offset();
     return false;
   }
   cie->cfa_instructions_offset = memory_.cur_offset() + aug_length;
@@ -422,24 +437,28 @@
     switch (cie->augmentation_string[i]) {
       case 'L':
         if (!memory_.ReadBytes(&cie->lsda_encoding, 1)) {
-          last_error_ = DWARF_ERROR_MEMORY_INVALID;
+          last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+          last_error_.address = memory_.cur_offset();
           return false;
         }
         break;
       case 'P': {
         uint8_t encoding;
         if (!memory_.ReadBytes(&encoding, 1)) {
-          last_error_ = DWARF_ERROR_MEMORY_INVALID;
+          last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+          last_error_.address = memory_.cur_offset();
           return false;
         }
         if (!memory_.ReadEncodedValue<AddressType>(encoding, &cie->personality_handler)) {
-          last_error_ = DWARF_ERROR_MEMORY_INVALID;
+          last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+          last_error_.address = memory_.cur_offset();
           return false;
         }
       } break;
       case 'R':
         if (!memory_.ReadBytes(&cie->fde_address_encoding, 1)) {
-          last_error_ = DWARF_ERROR_MEMORY_INVALID;
+          last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+          last_error_.address = memory_.cur_offset();
           return false;
         }
         break;
@@ -467,7 +486,8 @@
 bool DwarfSectionImpl<AddressType>::FillInFde(DwarfFde* fde) {
   uint32_t length32;
   if (!memory_.ReadBytes(&length32, sizeof(length32))) {
-    last_error_ = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.address = memory_.cur_offset();
     return false;
   }
 
@@ -475,19 +495,21 @@
     // 64 bit Fde.
     uint64_t length64;
     if (!memory_.ReadBytes(&length64, sizeof(length64))) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_.cur_offset();
       return false;
     }
     fde->cfa_instructions_end = memory_.cur_offset() + length64;
 
     uint64_t value64;
     if (!memory_.ReadBytes(&value64, sizeof(value64))) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_.cur_offset();
       return false;
     }
     if (value64 == cie64_value_) {
       // This is a Cie, this means something has gone wrong.
-      last_error_ = DWARF_ERROR_ILLEGAL_VALUE;
+      last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
       return false;
     }
 
@@ -500,12 +522,13 @@
 
     uint32_t value32;
     if (!memory_.ReadBytes(&value32, sizeof(value32))) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_.cur_offset();
       return false;
     }
     if (value32 == cie32_value_) {
       // This is a Cie, this means something has gone wrong.
-      last_error_ = DWARF_ERROR_ILLEGAL_VALUE;
+      last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
       return false;
     }
 
@@ -528,13 +551,15 @@
   memory_.set_cur_offset(cur_offset);
 
   if (!memory_.ReadEncodedValue<AddressType>(cie->fde_address_encoding & 0xf, &fde->pc_start)) {
-    last_error_ = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.address = memory_.cur_offset();
     return false;
   }
   fde->pc_start = AdjustPcFromFde(fde->pc_start);
 
   if (!memory_.ReadEncodedValue<AddressType>(cie->fde_address_encoding & 0xf, &fde->pc_end)) {
-    last_error_ = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.address = memory_.cur_offset();
     return false;
   }
   fde->pc_end += fde->pc_start;
@@ -542,13 +567,15 @@
     // Augmentation Size
     uint64_t aug_length;
     if (!memory_.ReadULEB128(&aug_length)) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_.cur_offset();
       return false;
     }
     uint64_t cur_offset = memory_.cur_offset();
 
     if (!memory_.ReadEncodedValue<AddressType>(cie->lsda_encoding, &fde->lsda_address)) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_.cur_offset();
       return false;
     }
 
@@ -619,7 +646,8 @@
 bool DwarfSectionImpl<AddressType>::GetCieInfo(uint8_t* segment_size, uint8_t* encoding) {
   uint8_t version;
   if (!memory_.ReadBytes(&version, 1)) {
-    last_error_ = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.address = memory_.cur_offset();
     return false;
   }
   // Read the augmentation string.
@@ -628,7 +656,8 @@
   bool get_encoding = false;
   do {
     if (!memory_.ReadBytes(&aug_value, 1)) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_.cur_offset();
       return false;
     }
     if (aug_value == 'R') {
@@ -643,7 +672,8 @@
 
     // Read the segment size.
     if (!memory_.ReadBytes(segment_size, 1)) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_.cur_offset();
       return false;
     }
   } else {
@@ -659,7 +689,8 @@
   uint8_t value;
   do {
     if (!memory_.ReadBytes(&value, 1)) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_.cur_offset();
       return false;
     }
   } while (value & 0x80);
@@ -667,7 +698,8 @@
   // Skip data alignment factor
   do {
     if (!memory_.ReadBytes(&value, 1)) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_.cur_offset();
       return false;
     }
   } while (value & 0x80);
@@ -679,7 +711,8 @@
     // Skip return address register.
     do {
       if (!memory_.ReadBytes(&value, 1)) {
-        last_error_ = DWARF_ERROR_MEMORY_INVALID;
+        last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+        last_error_.address = memory_.cur_offset();
         return false;
       }
     } while (value & 0x80);
@@ -688,7 +721,8 @@
   // Skip the augmentation length.
   do {
     if (!memory_.ReadBytes(&value, 1)) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_.cur_offset();
       return false;
     }
   } while (value & 0x80);
@@ -696,7 +730,8 @@
   for (size_t i = 1; i < aug_string.size(); i++) {
     if (aug_string[i] == 'R') {
       if (!memory_.ReadBytes(encoding, 1)) {
-        last_error_ = DWARF_ERROR_MEMORY_INVALID;
+        last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+        last_error_.address = memory_.cur_offset();
         return false;
       }
       // Got the encoding, that's all we are looking for.
@@ -706,12 +741,14 @@
     } else if (aug_string[i] == 'P') {
       uint8_t encoding;
       if (!memory_.ReadBytes(&encoding, 1)) {
-        last_error_ = DWARF_ERROR_MEMORY_INVALID;
+        last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+        last_error_.address = memory_.cur_offset();
         return false;
       }
       uint64_t value;
       if (!memory_.template ReadEncodedValue<AddressType>(encoding, &value)) {
-        last_error_ = DWARF_ERROR_MEMORY_INVALID;
+        last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+        last_error_.address = memory_.cur_offset();
         return false;
       }
     }
@@ -730,14 +767,16 @@
 
   uint64_t start;
   if (!memory_.template ReadEncodedValue<AddressType>(encoding & 0xf, &start)) {
-    last_error_ = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.address = memory_.cur_offset();
     return false;
   }
   start = AdjustPcFromFde(start);
 
   uint64_t length;
   if (!memory_.template ReadEncodedValue<AddressType>(encoding & 0xf, &length)) {
-    last_error_ = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+    last_error_.address = memory_.cur_offset();
     return false;
   }
   if (length != 0) {
@@ -764,7 +803,8 @@
     // Figure out the entry length and type.
     uint32_t value32;
     if (!memory_.ReadBytes(&value32, sizeof(value32))) {
-      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+      last_error_.address = memory_.cur_offset();
       return false;
     }
 
@@ -772,14 +812,16 @@
     if (value32 == static_cast<uint32_t>(-1)) {
       uint64_t value64;
       if (!memory_.ReadBytes(&value64, sizeof(value64))) {
-        last_error_ = DWARF_ERROR_MEMORY_INVALID;
+        last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+        last_error_.address = memory_.cur_offset();
         return false;
       }
       next_entry_offset = memory_.cur_offset() + value64;
 
       // Read the Cie Id of a Cie or the pointer of the Fde.
       if (!memory_.ReadBytes(&value64, sizeof(value64))) {
-        last_error_ = DWARF_ERROR_MEMORY_INVALID;
+        last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+        last_error_.address = memory_.cur_offset();
         return false;
       }
 
@@ -794,7 +836,7 @@
         uint64_t last_cie_offset = GetCieOffsetFromFde64(value64);
         if (last_cie_offset != cie_offset) {
           // This means that this Fde is not following the Cie.
-          last_error_ = DWARF_ERROR_ILLEGAL_VALUE;
+          last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
           return false;
         }
 
@@ -808,7 +850,8 @@
 
       // Read the Cie Id of a Cie or the pointer of the Fde.
       if (!memory_.ReadBytes(&value32, sizeof(value32))) {
-        last_error_ = DWARF_ERROR_MEMORY_INVALID;
+        last_error_.code = DWARF_ERROR_MEMORY_INVALID;
+        last_error_.address = memory_.cur_offset();
         return false;
       }
 
@@ -823,7 +866,7 @@
         uint64_t last_cie_offset = GetCieOffsetFromFde32(value32);
         if (last_cie_offset != cie_offset) {
           // This means that this Fde is not following the Cie.
-          last_error_ = DWARF_ERROR_ILLEGAL_VALUE;
+          last_error_.code = DWARF_ERROR_ILLEGAL_VALUE;
           return false;
         }
 
diff --git a/libunwindstack/Elf.cpp b/libunwindstack/Elf.cpp
index 220e549..f120da2 100644
--- a/libunwindstack/Elf.cpp
+++ b/libunwindstack/Elf.cpp
@@ -134,6 +134,26 @@
   return true;
 }
 
+void Elf::GetLastError(ErrorData* data) {
+  if (valid_) {
+    *data = interface_->last_error();
+  }
+}
+
+ErrorCode Elf::GetLastErrorCode() {
+  if (valid_) {
+    return interface_->LastErrorCode();
+  }
+  return ERROR_NONE;
+}
+
+uint64_t Elf::GetLastErrorAddress() {
+  if (valid_) {
+    return interface_->LastErrorAddress();
+  }
+  return 0;
+}
+
 // The relative pc is always relative to the start of the map from which it comes.
 bool Elf::Step(uint64_t rel_pc, uint64_t adjusted_rel_pc, uint64_t elf_offset, Regs* regs,
                Memory* process_memory, bool* finished) {
diff --git a/libunwindstack/ElfInterface.cpp b/libunwindstack/ElfInterface.cpp
index 17cc16a..e413081 100644
--- a/libunwindstack/ElfInterface.cpp
+++ b/libunwindstack/ElfInterface.cpp
@@ -24,6 +24,7 @@
 #include <Xz.h>
 #include <XzCrc64.h>
 
+#include <unwindstack/DwarfError.h>
 #include <unwindstack/DwarfSection.h>
 #include <unwindstack/ElfInterface.h>
 #include <unwindstack/Log.h>
@@ -160,6 +161,8 @@
 bool ElfInterface::ReadAllHeaders(uint64_t* load_bias) {
   EhdrType ehdr;
   if (!memory_->ReadFully(0, &ehdr, sizeof(ehdr))) {
+    last_error_.code = ERROR_MEMORY_INVALID;
+    last_error_.address = 0;
     return false;
   }
 
@@ -201,6 +204,9 @@
   for (size_t i = 0; i < ehdr.e_phnum; i++, offset += ehdr.e_phentsize) {
     PhdrType phdr;
     if (!memory_->ReadField(offset, &phdr, &phdr.p_type, sizeof(phdr.p_type))) {
+      last_error_.code = ERROR_MEMORY_INVALID;
+      last_error_.address =
+          offset + reinterpret_cast<uintptr_t>(&phdr.p_type) - reinterpret_cast<uintptr_t>(&phdr);
       return false;
     }
 
@@ -213,6 +219,9 @@
     {
       // Get the flags first, if this isn't an executable header, ignore it.
       if (!memory_->ReadField(offset, &phdr, &phdr.p_flags, sizeof(phdr.p_flags))) {
+        last_error_.code = ERROR_MEMORY_INVALID;
+        last_error_.address = offset + reinterpret_cast<uintptr_t>(&phdr.p_flags) -
+                              reinterpret_cast<uintptr_t>(&phdr);
         return false;
       }
       if ((phdr.p_flags & PF_X) == 0) {
@@ -220,12 +229,21 @@
       }
 
       if (!memory_->ReadField(offset, &phdr, &phdr.p_vaddr, sizeof(phdr.p_vaddr))) {
+        last_error_.code = ERROR_MEMORY_INVALID;
+        last_error_.address = offset + reinterpret_cast<uintptr_t>(&phdr.p_vaddr) -
+                              reinterpret_cast<uintptr_t>(&phdr);
         return false;
       }
       if (!memory_->ReadField(offset, &phdr, &phdr.p_offset, sizeof(phdr.p_offset))) {
+        last_error_.code = ERROR_MEMORY_INVALID;
+        last_error_.address = offset + reinterpret_cast<uintptr_t>(&phdr.p_offset) -
+                              reinterpret_cast<uintptr_t>(&phdr);
         return false;
       }
       if (!memory_->ReadField(offset, &phdr, &phdr.p_memsz, sizeof(phdr.p_memsz))) {
+        last_error_.code = ERROR_MEMORY_INVALID;
+        last_error_.address = offset + reinterpret_cast<uintptr_t>(&phdr.p_memsz) -
+                              reinterpret_cast<uintptr_t>(&phdr);
         return false;
       }
       pt_loads_[phdr.p_offset] = LoadInfo{phdr.p_offset, phdr.p_vaddr,
@@ -238,11 +256,17 @@
 
     case PT_GNU_EH_FRAME:
       if (!memory_->ReadField(offset, &phdr, &phdr.p_offset, sizeof(phdr.p_offset))) {
+        last_error_.code = ERROR_MEMORY_INVALID;
+        last_error_.address = offset + reinterpret_cast<uintptr_t>(&phdr.p_offset) -
+                              reinterpret_cast<uintptr_t>(&phdr);
         return false;
       }
       // This is really the pointer to the .eh_frame_hdr section.
       eh_frame_hdr_offset_ = phdr.p_offset;
       if (!memory_->ReadField(offset, &phdr, &phdr.p_memsz, sizeof(phdr.p_memsz))) {
+        last_error_.code = ERROR_MEMORY_INVALID;
+        last_error_.address = offset + reinterpret_cast<uintptr_t>(&phdr.p_memsz) -
+                              reinterpret_cast<uintptr_t>(&phdr);
         return false;
       }
       eh_frame_hdr_size_ = phdr.p_memsz;
@@ -250,14 +274,23 @@
 
     case PT_DYNAMIC:
       if (!memory_->ReadField(offset, &phdr, &phdr.p_offset, sizeof(phdr.p_offset))) {
+        last_error_.code = ERROR_MEMORY_INVALID;
+        last_error_.address = offset + reinterpret_cast<uintptr_t>(&phdr.p_offset) -
+                              reinterpret_cast<uintptr_t>(&phdr);
         return false;
       }
       dynamic_offset_ = phdr.p_offset;
       if (!memory_->ReadField(offset, &phdr, &phdr.p_vaddr, sizeof(phdr.p_vaddr))) {
+        last_error_.code = ERROR_MEMORY_INVALID;
+        last_error_.address = offset + reinterpret_cast<uintptr_t>(&phdr.p_vaddr) -
+                              reinterpret_cast<uintptr_t>(&phdr);
         return false;
       }
       dynamic_vaddr_ = phdr.p_vaddr;
       if (!memory_->ReadField(offset, &phdr, &phdr.p_memsz, sizeof(phdr.p_memsz))) {
+        last_error_.code = ERROR_MEMORY_INVALID;
+        last_error_.address = offset + reinterpret_cast<uintptr_t>(&phdr.p_memsz) -
+                              reinterpret_cast<uintptr_t>(&phdr);
         return false;
       }
       dynamic_size_ = phdr.p_memsz;
@@ -290,31 +323,47 @@
   offset += ehdr.e_shentsize;
   for (size_t i = 1; i < ehdr.e_shnum; i++, offset += ehdr.e_shentsize) {
     if (!memory_->ReadField(offset, &shdr, &shdr.sh_type, sizeof(shdr.sh_type))) {
+      last_error_.code = ERROR_MEMORY_INVALID;
+      last_error_.address =
+          offset + reinterpret_cast<uintptr_t>(&shdr.sh_type) - reinterpret_cast<uintptr_t>(&shdr);
       return false;
     }
 
     if (shdr.sh_type == SHT_SYMTAB || shdr.sh_type == SHT_DYNSYM) {
       if (!memory_->ReadFully(offset, &shdr, sizeof(shdr))) {
+        last_error_.code = ERROR_MEMORY_INVALID;
+        last_error_.address = offset;
         return false;
       }
       // Need to go get the information about the section that contains
       // the string terminated names.
       ShdrType str_shdr;
       if (shdr.sh_link >= ehdr.e_shnum) {
+        last_error_.code = ERROR_UNWIND_INFO;
         return false;
       }
       uint64_t str_offset = ehdr.e_shoff + shdr.sh_link * ehdr.e_shentsize;
       if (!memory_->ReadField(str_offset, &str_shdr, &str_shdr.sh_type, sizeof(str_shdr.sh_type))) {
+        last_error_.code = ERROR_MEMORY_INVALID;
+        last_error_.address = str_offset + reinterpret_cast<uintptr_t>(&str_shdr.sh_type) -
+                              reinterpret_cast<uintptr_t>(&str_shdr);
         return false;
       }
       if (str_shdr.sh_type != SHT_STRTAB) {
+        last_error_.code = ERROR_UNWIND_INFO;
         return false;
       }
       if (!memory_->ReadField(str_offset, &str_shdr, &str_shdr.sh_offset,
                               sizeof(str_shdr.sh_offset))) {
+        last_error_.code = ERROR_MEMORY_INVALID;
+        last_error_.address = str_offset + reinterpret_cast<uintptr_t>(&str_shdr.sh_offset) -
+                              reinterpret_cast<uintptr_t>(&str_shdr);
         return false;
       }
       if (!memory_->ReadField(str_offset, &str_shdr, &str_shdr.sh_size, sizeof(str_shdr.sh_size))) {
+        last_error_.code = ERROR_MEMORY_INVALID;
+        last_error_.address = str_offset + reinterpret_cast<uintptr_t>(&str_shdr.sh_size) -
+                              reinterpret_cast<uintptr_t>(&str_shdr);
         return false;
       }
       symbols_.push_back(new Symbols(shdr.sh_offset, shdr.sh_size, shdr.sh_entsize,
@@ -322,6 +371,9 @@
     } else if (shdr.sh_type == SHT_PROGBITS && sec_size != 0) {
       // Look for the .debug_frame and .gnu_debugdata.
       if (!memory_->ReadField(offset, &shdr, &shdr.sh_name, sizeof(shdr.sh_name))) {
+        last_error_.code = ERROR_MEMORY_INVALID;
+        last_error_.address = offset + reinterpret_cast<uintptr_t>(&shdr.sh_name) -
+                              reinterpret_cast<uintptr_t>(&shdr);
         return false;
       }
       if (shdr.sh_name < sec_size) {
@@ -377,6 +429,8 @@
   uint64_t max_offset = offset + dynamic_size_;
   for (uint64_t offset = dynamic_offset_; offset < max_offset; offset += sizeof(DynType)) {
     if (!memory_->ReadFully(offset, &dyn, sizeof(dyn))) {
+      last_error_.code = ERROR_MEMORY_INVALID;
+      last_error_.address = offset;
       return false;
     }
 
@@ -434,8 +488,12 @@
 
 bool ElfInterface::Step(uint64_t pc, uint64_t load_bias, Regs* regs, Memory* process_memory,
                         bool* finished) {
+  last_error_.code = ERROR_NONE;
+  last_error_.address = 0;
+
   // Adjust the load bias to get the real relative pc.
   if (pc < load_bias) {
+    last_error_.code = ERROR_UNWIND_INFO;
     return false;
   }
   uint64_t adjusted_pc = pc - load_bias;
@@ -458,6 +516,46 @@
       gnu_debugdata_interface_->Step(pc, 0, regs, process_memory, finished)) {
     return true;
   }
+
+  // Set the error code based on the first error encountered.
+  DwarfSection* section = nullptr;
+  if (debug_frame_ != nullptr) {
+    section = debug_frame_.get();
+  } else if (eh_frame_ != nullptr) {
+    section = eh_frame_.get();
+  } else if (gnu_debugdata_interface_ != nullptr) {
+    last_error_ = gnu_debugdata_interface_->last_error();
+    return false;
+  } else {
+    return false;
+  }
+
+  // Convert the DWARF ERROR to an external error.
+  DwarfErrorCode code = section->LastErrorCode();
+  switch (code) {
+    case DWARF_ERROR_NONE:
+      last_error_.code = ERROR_NONE;
+      break;
+
+    case DWARF_ERROR_MEMORY_INVALID:
+      last_error_.code = ERROR_MEMORY_INVALID;
+      last_error_.address = section->LastErrorAddress();
+      break;
+
+    case DWARF_ERROR_ILLEGAL_VALUE:
+    case DWARF_ERROR_ILLEGAL_STATE:
+    case DWARF_ERROR_STACK_INDEX_NOT_VALID:
+    case DWARF_ERROR_TOO_MANY_ITERATIONS:
+    case DWARF_ERROR_CFA_NOT_DEFINED:
+    case DWARF_ERROR_NO_FDES:
+      last_error_.code = ERROR_UNWIND_INFO;
+      break;
+
+    case DWARF_ERROR_NOT_IMPLEMENTED:
+    case DWARF_ERROR_UNSUPPORTED_VERSION:
+      last_error_.code = ERROR_UNSUPPORTED;
+      break;
+  }
   return false;
 }
 
diff --git a/libunwindstack/ElfInterfaceArm.cpp b/libunwindstack/ElfInterfaceArm.cpp
index 5d99bd7..616d1b1 100644
--- a/libunwindstack/ElfInterfaceArm.cpp
+++ b/libunwindstack/ElfInterfaceArm.cpp
@@ -28,6 +28,7 @@
 
 bool ElfInterfaceArm::FindEntry(uint32_t pc, uint64_t* entry_offset) {
   if (start_offset_ == 0 || total_entries_ == 0) {
+    last_error_.code = ERROR_UNWIND_INFO;
     return false;
   }
 
@@ -56,12 +57,15 @@
     *entry_offset = start_offset_ + (last - 1) * 8;
     return true;
   }
+  last_error_.code = ERROR_UNWIND_INFO;
   return false;
 }
 
 bool ElfInterfaceArm::GetPrel31Addr(uint32_t offset, uint32_t* addr) {
   uint32_t data;
   if (!memory_->Read32(offset, &data)) {
+    last_error_.code = ERROR_MEMORY_INVALID;
+    last_error_.address = offset;
     return false;
   }
 
@@ -106,6 +110,7 @@
                                 bool* finished) {
   // Adjust the load bias to get the real relative pc.
   if (pc < load_bias) {
+    last_error_.code = ERROR_UNWIND_INFO;
     return false;
   }
   pc -= load_bias;
@@ -139,6 +144,30 @@
     *finished = true;
     return true;
   }
+
+  if (!return_value) {
+    switch (arm.status()) {
+      case ARM_STATUS_NONE:
+      case ARM_STATUS_NO_UNWIND:
+      case ARM_STATUS_FINISH:
+        last_error_.code = ERROR_NONE;
+        break;
+
+      case ARM_STATUS_RESERVED:
+      case ARM_STATUS_SPARE:
+      case ARM_STATUS_TRUNCATED:
+      case ARM_STATUS_MALFORMED:
+      case ARM_STATUS_INVALID_ALIGNMENT:
+      case ARM_STATUS_INVALID_PERSONALITY:
+        last_error_.code = ERROR_UNWIND_INFO;
+        break;
+
+      case ARM_STATUS_READ_FAILED:
+        last_error_.code = ERROR_MEMORY_INVALID;
+        last_error_.address = arm.status_address();
+        break;
+    }
+  }
   return return_value;
 }
 
diff --git a/libunwindstack/Unwinder.cpp b/libunwindstack/Unwinder.cpp
index d711772..f70ed7b 100644
--- a/libunwindstack/Unwinder.cpp
+++ b/libunwindstack/Unwinder.cpp
@@ -78,6 +78,8 @@
 void Unwinder::Unwind(const std::vector<std::string>* initial_map_names_to_skip,
                       const std::vector<std::string>* map_suffixes_to_ignore) {
   frames_.clear();
+  last_error_.code = ERROR_NONE;
+  last_error_.address = 0;
 
   bool return_address_attempt = false;
   bool adjust_pc = false;
@@ -95,6 +97,7 @@
       rel_pc = regs_->pc();
       adjusted_rel_pc = rel_pc;
       adjusted_pc = rel_pc;
+      last_error_.code = ERROR_INVALID_MAP;
     } else {
       if (ShouldStop(map_suffixes_to_ignore, map_info->name)) {
         break;
@@ -155,6 +158,7 @@
           bool finished;
           stepped = elf->Step(rel_pc, adjusted_pc, map_info->elf_offset, regs_,
                               process_memory_.get(), &finished);
+          elf->GetLastError(&last_error_);
           if (stepped && finished) {
             break;
           }
@@ -180,10 +184,14 @@
       }
     } else {
       return_address_attempt = false;
+      if (max_frames_ == frames_.size()) {
+        last_error_.code = ERROR_MAX_FRAMES_EXCEEDED;
+      }
     }
 
     // If the pc and sp didn't change, then consider everything stopped.
     if (cur_pc == regs_->pc() && cur_sp == regs_->sp()) {
+      last_error_.code = ERROR_REPEATED_FRAME;
       break;
     }
   }
diff --git a/libunwindstack/include/unwindstack/DwarfError.h b/libunwindstack/include/unwindstack/DwarfError.h
new file mode 100644
index 0000000..763e2cb
--- /dev/null
+++ b/libunwindstack/include/unwindstack/DwarfError.h
@@ -0,0 +1,44 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _LIBUNWINDSTACK_DWARF_ERROR_H
+#define _LIBUNWINDSTACK_DWARF_ERROR_H
+
+#include <stdint.h>
+
+namespace unwindstack {
+
+enum DwarfErrorCode : uint8_t {
+  DWARF_ERROR_NONE,
+  DWARF_ERROR_MEMORY_INVALID,
+  DWARF_ERROR_ILLEGAL_VALUE,
+  DWARF_ERROR_ILLEGAL_STATE,
+  DWARF_ERROR_STACK_INDEX_NOT_VALID,
+  DWARF_ERROR_NOT_IMPLEMENTED,
+  DWARF_ERROR_TOO_MANY_ITERATIONS,
+  DWARF_ERROR_CFA_NOT_DEFINED,
+  DWARF_ERROR_UNSUPPORTED_VERSION,
+  DWARF_ERROR_NO_FDES,
+};
+
+struct DwarfErrorData {
+  DwarfErrorCode code;
+  uint64_t address;
+};
+
+}  // namespace unwindstack
+
+#endif  // _LIBUNWINDSTACK_DWARF_ERROR_H
diff --git a/libunwindstack/include/unwindstack/DwarfSection.h b/libunwindstack/include/unwindstack/DwarfSection.h
index e0004aa..03f40d6 100644
--- a/libunwindstack/include/unwindstack/DwarfSection.h
+++ b/libunwindstack/include/unwindstack/DwarfSection.h
@@ -22,6 +22,7 @@
 #include <iterator>
 #include <unordered_map>
 
+#include <unwindstack/DwarfError.h>
 #include <unwindstack/DwarfLocation.h>
 #include <unwindstack/DwarfMemory.h>
 #include <unwindstack/DwarfStructs.h>
@@ -29,7 +30,6 @@
 namespace unwindstack {
 
 // Forward declarations.
-enum DwarfError : uint8_t;
 class Memory;
 class Regs;
 
@@ -72,7 +72,8 @@
   iterator begin() { return iterator(this, 0); }
   iterator end() { return iterator(this, fde_count_); }
 
-  DwarfError last_error() { return last_error_; }
+  DwarfErrorCode LastErrorCode() { return last_error_.code; }
+  uint64_t LastErrorAddress() { return last_error_.address; }
 
   virtual bool Init(uint64_t offset, uint64_t size) = 0;
 
@@ -100,7 +101,7 @@
 
  protected:
   DwarfMemory memory_;
-  DwarfError last_error_;
+  DwarfErrorData last_error_{DWARF_ERROR_NONE, 0};
 
   uint32_t cie32_value_ = 0;
   uint64_t cie64_value_ = 0;
diff --git a/libunwindstack/include/unwindstack/Elf.h b/libunwindstack/include/unwindstack/Elf.h
index 5f34391..e562d6d 100644
--- a/libunwindstack/include/unwindstack/Elf.h
+++ b/libunwindstack/include/unwindstack/Elf.h
@@ -72,6 +72,10 @@
 
   bool IsValidPc(uint64_t pc);
 
+  void GetLastError(ErrorData* data);
+  ErrorCode GetLastErrorCode();
+  uint64_t GetLastErrorAddress();
+
   bool valid() { return valid_; }
 
   uint32_t machine_type() { return machine_type_; }
diff --git a/libunwindstack/include/unwindstack/ElfInterface.h b/libunwindstack/include/unwindstack/ElfInterface.h
index faa61ee..ea9ec9d 100644
--- a/libunwindstack/include/unwindstack/ElfInterface.h
+++ b/libunwindstack/include/unwindstack/ElfInterface.h
@@ -26,6 +26,7 @@
 #include <vector>
 
 #include <unwindstack/DwarfSection.h>
+#include <unwindstack/Error.h>
 
 namespace unwindstack {
 
@@ -90,6 +91,10 @@
   DwarfSection* eh_frame() { return eh_frame_.get(); }
   DwarfSection* debug_frame() { return debug_frame_.get(); }
 
+  const ErrorData& last_error() { return last_error_; }
+  ErrorCode LastErrorCode() { return last_error_.code; }
+  uint64_t LastErrorAddress() { return last_error_.address; }
+
   template <typename EhdrType, typename PhdrType>
   static uint64_t GetLoadBias(Memory* memory);
 
@@ -144,6 +149,8 @@
   uint8_t soname_type_ = SONAME_UNKNOWN;
   std::string soname_;
 
+  ErrorData last_error_{ERROR_NONE, 0};
+
   std::unique_ptr<DwarfSection> eh_frame_;
   std::unique_ptr<DwarfSection> debug_frame_;
   // The Elf object owns the gnu_debugdata interface object.
diff --git a/libunwindstack/include/unwindstack/Error.h b/libunwindstack/include/unwindstack/Error.h
new file mode 100644
index 0000000..6ed0e0f
--- /dev/null
+++ b/libunwindstack/include/unwindstack/Error.h
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _LIBUNWINDSTACK_ERROR_H
+#define _LIBUNWINDSTACK_ERROR_H
+
+#include <stdint.h>
+
+namespace unwindstack {
+
+enum ErrorCode : uint8_t {
+  ERROR_NONE,                 // No error.
+  ERROR_MEMORY_INVALID,       // Memory read failed.
+  ERROR_UNWIND_INFO,          // Unable to use unwind information to unwind.
+  ERROR_UNSUPPORTED,          // Encountered unsupported feature.
+  ERROR_INVALID_MAP,          // Unwind in an invalid map.
+  ERROR_MAX_FRAMES_EXCEEDED,  // The number of frames exceed the total allowed.
+  ERROR_REPEATED_FRAME,       // The last frame has the same pc/sp as the next.
+};
+
+struct ErrorData {
+  ErrorCode code;
+  uint64_t address;  // Only valid when code is ERROR_MEMORY_INVALID.
+                     // Indicates the failing address.
+};
+
+}  // namespace unwindstack
+
+#endif  // _LIBUNWINDSTACK_ERROR_H
diff --git a/libunwindstack/include/unwindstack/Unwinder.h b/libunwindstack/include/unwindstack/Unwinder.h
index 32858ae..a7b57e6 100644
--- a/libunwindstack/include/unwindstack/Unwinder.h
+++ b/libunwindstack/include/unwindstack/Unwinder.h
@@ -24,6 +24,7 @@
 #include <string>
 #include <vector>
 
+#include <unwindstack/Error.h>
 #include <unwindstack/Maps.h>
 #include <unwindstack/Memory.h>
 #include <unwindstack/Regs.h>
@@ -74,6 +75,9 @@
 
   void SetJitDebug(JitDebug* jit_debug, ArchEnum arch);
 
+  ErrorCode LastErrorCode() { return last_error_.code; }
+  uint64_t LastErrorAddress() { return last_error_.address; }
+
  private:
   void FillInFrame(MapInfo* map_info, Elf* elf, uint64_t adjusted_rel_pc, uint64_t adjusted_pc);
 
@@ -83,6 +87,7 @@
   std::vector<FrameData> frames_;
   std::shared_ptr<Memory> process_memory_;
   JitDebug* jit_debug_ = nullptr;
+  ErrorData last_error_;
 };
 
 }  // namespace unwindstack
diff --git a/libunwindstack/tests/ArmExidxExtractTest.cpp b/libunwindstack/tests/ArmExidxExtractTest.cpp
index caad131..8d0f0e5 100644
--- a/libunwindstack/tests/ArmExidxExtractTest.cpp
+++ b/libunwindstack/tests/ArmExidxExtractTest.cpp
@@ -257,22 +257,27 @@
 TEST_F(ArmExidxExtractTest, read_failures) {
   ASSERT_FALSE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(ARM_STATUS_READ_FAILED, exidx_->status());
+  EXPECT_EQ(0x5004U, exidx_->status_address());
 
   elf_memory_.SetData32(0x5000, 0x100);
   ASSERT_FALSE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(ARM_STATUS_READ_FAILED, exidx_->status());
+  EXPECT_EQ(0x5004U, exidx_->status_address());
 
   elf_memory_.SetData32(0x5004, 0x100);
   ASSERT_FALSE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(ARM_STATUS_READ_FAILED, exidx_->status());
+  EXPECT_EQ(0x5104U, exidx_->status_address());
 
   elf_memory_.SetData32(0x5104, 0x1);
   ASSERT_FALSE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(ARM_STATUS_READ_FAILED, exidx_->status());
+  EXPECT_EQ(0x5108U, exidx_->status_address());
 
   elf_memory_.SetData32(0x5108, 0x01010203);
   ASSERT_FALSE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(ARM_STATUS_READ_FAILED, exidx_->status());
+  EXPECT_EQ(0x510cU, exidx_->status_address());
 }
 
 TEST_F(ArmExidxExtractTest, malformed) {
diff --git a/libunwindstack/tests/DwarfCfaTest.cpp b/libunwindstack/tests/DwarfCfaTest.cpp
index 73a67ac..68dc30c 100644
--- a/libunwindstack/tests/DwarfCfaTest.cpp
+++ b/libunwindstack/tests/DwarfCfaTest.cpp
@@ -21,13 +21,13 @@
 
 #include <gtest/gtest.h>
 
+#include <unwindstack/DwarfError.h>
 #include <unwindstack/DwarfLocation.h>
 #include <unwindstack/DwarfMemory.h>
 #include <unwindstack/DwarfStructs.h>
 #include <unwindstack/Log.h>
 
 #include "DwarfCfa.h"
-#include "DwarfError.h"
 
 #include "LogFake.h"
 #include "MemoryFake.h"
@@ -78,7 +78,7 @@
     dwarf_loc_regs_t loc_regs;
 
     ASSERT_FALSE(this->cfa_->GetLocationInfo(this->fde_.pc_start, 0x2000, 0x2001, &loc_regs));
-    ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->cfa_->last_error());
+    ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->cfa_->LastErrorCode());
     ASSERT_EQ(0x2001U, this->dmem_->cur_offset());
 
     ASSERT_EQ("", GetFakeLogPrint());
@@ -198,7 +198,7 @@
   dwarf_loc_regs_t loc_regs;
 
   ASSERT_FALSE(this->cfa_->GetLocationInfo(this->fde_.pc_start, 0x2000, 0x2001, &loc_regs));
-  ASSERT_EQ(DWARF_ERROR_ILLEGAL_STATE, this->cfa_->last_error());
+  ASSERT_EQ(DWARF_ERROR_ILLEGAL_STATE, this->cfa_->LastErrorCode());
   ASSERT_EQ(0x2001U, this->dmem_->cur_offset());
   ASSERT_EQ(0U, loc_regs.size());
 
@@ -227,7 +227,7 @@
   dwarf_loc_regs_t loc_regs;
 
   ASSERT_FALSE(this->cfa_->GetLocationInfo(this->fde_.pc_start, 0x4000, 0x4002, &loc_regs));
-  ASSERT_EQ(DWARF_ERROR_ILLEGAL_STATE, this->cfa_->last_error());
+  ASSERT_EQ(DWARF_ERROR_ILLEGAL_STATE, this->cfa_->LastErrorCode());
   ASSERT_EQ(0x4002U, this->dmem_->cur_offset());
   ASSERT_EQ(0U, loc_regs.size());
 
@@ -594,7 +594,7 @@
   // This fails because the cfa is not defined as a register.
   ASSERT_FALSE(this->cfa_->GetLocationInfo(this->fde_.pc_start, 0x100, 0x102, &loc_regs));
   ASSERT_EQ(0U, loc_regs.size());
-  ASSERT_EQ(DWARF_ERROR_ILLEGAL_STATE, this->cfa_->last_error());
+  ASSERT_EQ(DWARF_ERROR_ILLEGAL_STATE, this->cfa_->LastErrorCode());
 
   ASSERT_EQ("4 unwind Attempt to set new register, but cfa is not already set to a register.\n",
             GetFakeLogPrint());
@@ -637,7 +637,7 @@
   // This fails because the cfa is not defined as a register.
   ASSERT_FALSE(this->cfa_->GetLocationInfo(this->fde_.pc_start, 0x100, 0x102, &loc_regs));
   ASSERT_EQ(0U, loc_regs.size());
-  ASSERT_EQ(DWARF_ERROR_ILLEGAL_STATE, this->cfa_->last_error());
+  ASSERT_EQ(DWARF_ERROR_ILLEGAL_STATE, this->cfa_->LastErrorCode());
 
   ASSERT_EQ("4 unwind Attempt to set offset, but cfa is not set to a register.\n",
             GetFakeLogPrint());
@@ -679,7 +679,7 @@
 
   // This fails because the cfa is not defined as a register.
   ASSERT_FALSE(this->cfa_->GetLocationInfo(this->fde_.pc_start, 0x100, 0x102, &loc_regs));
-  ASSERT_EQ(DWARF_ERROR_ILLEGAL_STATE, this->cfa_->last_error());
+  ASSERT_EQ(DWARF_ERROR_ILLEGAL_STATE, this->cfa_->LastErrorCode());
 
   ASSERT_EQ("4 unwind Attempt to set offset, but cfa is not set to a register.\n",
             GetFakeLogPrint());
diff --git a/libunwindstack/tests/DwarfDebugFrameTest.cpp b/libunwindstack/tests/DwarfDebugFrameTest.cpp
index 243198e..c28a41e 100644
--- a/libunwindstack/tests/DwarfDebugFrameTest.cpp
+++ b/libunwindstack/tests/DwarfDebugFrameTest.cpp
@@ -19,9 +19,10 @@
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
 
+#include <unwindstack/DwarfError.h>
+
 #include "DwarfDebugFrame.h"
 #include "DwarfEncoding.h"
-#include "DwarfError.h"
 
 #include "LogFake.h"
 #include "MemoryFake.h"
@@ -142,7 +143,7 @@
   this->memory_.SetData32(0x510c, 0x200);
 
   ASSERT_FALSE(this->debug_frame_->Init(0x5000, 0x600));
-  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->debug_frame_->last_error());
+  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->debug_frame_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfDebugFrameTest, Init32_do_not_fail_on_bad_next_entry) {
@@ -267,7 +268,7 @@
   this->memory_.SetData64(0x511c, 0x200);
 
   ASSERT_FALSE(this->debug_frame_->Init(0x5000, 0x600));
-  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->debug_frame_->last_error());
+  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->debug_frame_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfDebugFrameTest, Init64_do_not_fail_on_bad_next_entry) {
@@ -404,11 +405,11 @@
   this->debug_frame_->TestSetFdeCount(0);
   uint64_t fde_offset;
   ASSERT_FALSE(this->debug_frame_->GetFdeOffsetFromPc(0x1000, &fde_offset));
-  ASSERT_EQ(DWARF_ERROR_NONE, this->debug_frame_->last_error());
+  ASSERT_EQ(DWARF_ERROR_NONE, this->debug_frame_->LastErrorCode());
 
   this->debug_frame_->TestSetFdeCount(9);
   ASSERT_FALSE(this->debug_frame_->GetFdeOffsetFromPc(0x100, &fde_offset));
-  ASSERT_EQ(DWARF_ERROR_NONE, this->debug_frame_->last_error());
+  ASSERT_EQ(DWARF_ERROR_NONE, this->debug_frame_->LastErrorCode());
   // Odd number of elements.
   for (size_t i = 0; i < 9; i++) {
     TypeParam pc = 0x1000 * (i + 1);
@@ -422,7 +423,7 @@
     EXPECT_EQ(0x5000 + i * 0x20, fde_offset) << "Failed at index " << i;
     ASSERT_FALSE(this->debug_frame_->GetFdeOffsetFromPc(pc + 0xfff, &fde_offset))
         << "Failed at index " << i;
-    ASSERT_EQ(DWARF_ERROR_NONE, this->debug_frame_->last_error());
+    ASSERT_EQ(DWARF_ERROR_NONE, this->debug_frame_->LastErrorCode());
   }
 
   // Even number of elements.
@@ -444,7 +445,7 @@
     EXPECT_EQ(0x5000 + i * 0x20, fde_offset) << "Failed at index " << i;
     ASSERT_FALSE(this->debug_frame_->GetFdeOffsetFromPc(pc + 0xfff, &fde_offset))
         << "Failed at index " << i;
-    ASSERT_EQ(DWARF_ERROR_NONE, this->debug_frame_->last_error());
+    ASSERT_EQ(DWARF_ERROR_NONE, this->debug_frame_->LastErrorCode());
   }
 }
 
diff --git a/libunwindstack/tests/DwarfEhFrameTest.cpp b/libunwindstack/tests/DwarfEhFrameTest.cpp
index 3a629f8..a73db65 100644
--- a/libunwindstack/tests/DwarfEhFrameTest.cpp
+++ b/libunwindstack/tests/DwarfEhFrameTest.cpp
@@ -19,9 +19,10 @@
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
 
+#include <unwindstack/DwarfError.h>
+
 #include "DwarfEhFrame.h"
 #include "DwarfEncoding.h"
-#include "DwarfError.h"
 
 #include "LogFake.h"
 #include "MemoryFake.h"
@@ -142,7 +143,7 @@
   this->memory_.SetData32(0x510c, 0x200);
 
   ASSERT_FALSE(this->eh_frame_->Init(0x5000, 0x600));
-  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->eh_frame_->last_error());
+  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->eh_frame_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfEhFrameTest, Init64) {
@@ -228,7 +229,7 @@
   this->memory_.SetData64(0x511c, 0x200);
 
   ASSERT_FALSE(this->eh_frame_->Init(0x5000, 0x600));
-  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->eh_frame_->last_error());
+  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->eh_frame_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfEhFrameTest, Init_version1) {
@@ -320,11 +321,11 @@
   this->eh_frame_->TestSetFdeCount(0);
   uint64_t fde_offset;
   ASSERT_FALSE(this->eh_frame_->GetFdeOffsetFromPc(0x1000, &fde_offset));
-  ASSERT_EQ(DWARF_ERROR_NONE, this->eh_frame_->last_error());
+  ASSERT_EQ(DWARF_ERROR_NONE, this->eh_frame_->LastErrorCode());
 
   this->eh_frame_->TestSetFdeCount(9);
   ASSERT_FALSE(this->eh_frame_->GetFdeOffsetFromPc(0x100, &fde_offset));
-  ASSERT_EQ(DWARF_ERROR_NONE, this->eh_frame_->last_error());
+  ASSERT_EQ(DWARF_ERROR_NONE, this->eh_frame_->LastErrorCode());
   // Odd number of elements.
   for (size_t i = 0; i < 9; i++) {
     TypeParam pc = 0x1000 * (i + 1);
@@ -337,7 +338,7 @@
     EXPECT_EQ(0x5000 + i * 0x20, fde_offset) << "Failed at index " << i;
     ASSERT_FALSE(this->eh_frame_->GetFdeOffsetFromPc(pc + 0xfff, &fde_offset))
         << "Failed at index " << i;
-    ASSERT_EQ(DWARF_ERROR_NONE, this->eh_frame_->last_error());
+    ASSERT_EQ(DWARF_ERROR_NONE, this->eh_frame_->LastErrorCode());
   }
 
   // Even number of elements.
@@ -358,7 +359,7 @@
     EXPECT_EQ(0x5000 + i * 0x20, fde_offset) << "Failed at index " << i;
     ASSERT_FALSE(this->eh_frame_->GetFdeOffsetFromPc(pc + 0xfff, &fde_offset))
         << "Failed at index " << i;
-    ASSERT_EQ(DWARF_ERROR_NONE, this->eh_frame_->last_error());
+    ASSERT_EQ(DWARF_ERROR_NONE, this->eh_frame_->LastErrorCode());
   }
 }
 
diff --git a/libunwindstack/tests/DwarfEhFrameWithHdrTest.cpp b/libunwindstack/tests/DwarfEhFrameWithHdrTest.cpp
index ef2fb32..a2ae5eb 100644
--- a/libunwindstack/tests/DwarfEhFrameWithHdrTest.cpp
+++ b/libunwindstack/tests/DwarfEhFrameWithHdrTest.cpp
@@ -19,9 +19,10 @@
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
 
+#include <unwindstack/DwarfError.h>
+
 #include "DwarfEhFrameWithHdr.h"
 #include "DwarfEncoding.h"
-#include "DwarfError.h"
 
 #include "LogFake.h"
 #include "MemoryFake.h"
@@ -97,25 +98,29 @@
   // Verify a zero fde count fails to init.
   this->memory_.SetData32(0x1006, 0);
   ASSERT_FALSE(this->eh_frame_->Init(0x1000, 0x100));
-  ASSERT_EQ(DWARF_ERROR_NO_FDES, this->eh_frame_->last_error());
+  ASSERT_EQ(DWARF_ERROR_NO_FDES, this->eh_frame_->LastErrorCode());
 
   // Verify an unexpected version will cause a fail.
   this->memory_.SetData32(0x1006, 126);
   this->memory_.SetData8(0x1000, 0);
   ASSERT_FALSE(this->eh_frame_->Init(0x1000, 0x100));
-  ASSERT_EQ(DWARF_ERROR_UNSUPPORTED_VERSION, this->eh_frame_->last_error());
+  ASSERT_EQ(DWARF_ERROR_UNSUPPORTED_VERSION, this->eh_frame_->LastErrorCode());
   this->memory_.SetData8(0x1000, 2);
   ASSERT_FALSE(this->eh_frame_->Init(0x1000, 0x100));
-  ASSERT_EQ(DWARF_ERROR_UNSUPPORTED_VERSION, this->eh_frame_->last_error());
+  ASSERT_EQ(DWARF_ERROR_UNSUPPORTED_VERSION, this->eh_frame_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfEhFrameWithHdrTest, GetFdeInfoFromIndex_expect_cache_fail) {
   this->eh_frame_->TestSetTableEntrySize(0x10);
   this->eh_frame_->TestSetTableEncoding(DW_EH_PE_udata4);
+  this->eh_frame_->TestSetEntriesOffset(0x1000);
+
   ASSERT_TRUE(this->eh_frame_->GetFdeInfoFromIndex(0) == nullptr);
-  ASSERT_EQ(DWARF_ERROR_MEMORY_INVALID, this->eh_frame_->last_error());
+  ASSERT_EQ(DWARF_ERROR_MEMORY_INVALID, this->eh_frame_->LastErrorCode());
+  EXPECT_EQ(0x1000U, this->eh_frame_->LastErrorAddress());
   ASSERT_TRUE(this->eh_frame_->GetFdeInfoFromIndex(0) == nullptr);
-  ASSERT_EQ(DWARF_ERROR_MEMORY_INVALID, this->eh_frame_->last_error());
+  ASSERT_EQ(DWARF_ERROR_MEMORY_INVALID, this->eh_frame_->LastErrorCode());
+  EXPECT_EQ(0x1000U, this->eh_frame_->LastErrorAddress());
 }
 
 TYPED_TEST_P(DwarfEhFrameWithHdrTest, GetFdeInfoFromIndex_read_pcrel) {
@@ -184,7 +189,7 @@
   uint64_t fde_offset;
   EXPECT_FALSE(this->eh_frame_->GetFdeOffsetBinary(0x100, &fde_offset, 10));
   // Not an error, just not found.
-  ASSERT_EQ(DWARF_ERROR_NONE, this->eh_frame_->last_error());
+  ASSERT_EQ(DWARF_ERROR_NONE, this->eh_frame_->LastErrorCode());
   // Even number of elements.
   for (size_t i = 0; i < 10; i++) {
     TypeParam pc = 0x1000 * (i + 1);
@@ -280,7 +285,7 @@
 
   uint64_t fde_offset;
   ASSERT_FALSE(this->eh_frame_->GetFdeOffsetSequential(0x540, &fde_offset));
-  ASSERT_EQ(DWARF_ERROR_NONE, this->eh_frame_->last_error());
+  ASSERT_EQ(DWARF_ERROR_NONE, this->eh_frame_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfEhFrameWithHdrTest, GetFdeOffsetFromPc_fail_fde_count) {
@@ -288,7 +293,7 @@
 
   uint64_t fde_offset;
   ASSERT_FALSE(this->eh_frame_->GetFdeOffsetFromPc(0x100, &fde_offset));
-  ASSERT_EQ(DWARF_ERROR_NONE, this->eh_frame_->last_error());
+  ASSERT_EQ(DWARF_ERROR_NONE, this->eh_frame_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfEhFrameWithHdrTest, GetFdeOffsetFromPc_binary_search) {
diff --git a/libunwindstack/tests/DwarfOpLogTest.cpp b/libunwindstack/tests/DwarfOpLogTest.cpp
index 234d1c9..3f09dd8 100644
--- a/libunwindstack/tests/DwarfOpLogTest.cpp
+++ b/libunwindstack/tests/DwarfOpLogTest.cpp
@@ -21,11 +21,11 @@
 
 #include <gtest/gtest.h>
 
+#include <unwindstack/DwarfError.h>
 #include <unwindstack/DwarfMemory.h>
 #include <unwindstack/Log.h>
 #include <unwindstack/Regs.h>
 
-#include "DwarfError.h"
 #include "DwarfOp.h"
 
 #include "MemoryFake.h"
diff --git a/libunwindstack/tests/DwarfOpTest.cpp b/libunwindstack/tests/DwarfOpTest.cpp
index 2d5007b..036226d 100644
--- a/libunwindstack/tests/DwarfOpTest.cpp
+++ b/libunwindstack/tests/DwarfOpTest.cpp
@@ -21,10 +21,10 @@
 
 #include <gtest/gtest.h>
 
+#include <unwindstack/DwarfError.h>
 #include <unwindstack/DwarfMemory.h>
 #include <unwindstack/Log.h>
 
-#include "DwarfError.h"
 #include "DwarfOp.h"
 
 #include "MemoryFake.h"
@@ -53,13 +53,14 @@
 TYPED_TEST_P(DwarfOpTest, decode) {
   // Memory error.
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_MEMORY_INVALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_MEMORY_INVALID, this->op_->LastErrorCode());
+  EXPECT_EQ(0U, this->op_->LastErrorAddress());
 
   // No error.
   this->op_memory_.SetMemory(0, std::vector<uint8_t>{0x96});
   this->mem_->set_cur_offset(0);
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_NONE, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_NONE, this->op_->LastErrorCode());
   ASSERT_EQ(0x96U, this->op_->cur_op());
   ASSERT_EQ(1U, this->mem_->cur_offset());
 }
@@ -67,7 +68,8 @@
 TYPED_TEST_P(DwarfOpTest, eval) {
   // Memory error.
   ASSERT_FALSE(this->op_->Eval(0, 2, DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_MEMORY_INVALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_MEMORY_INVALID, this->op_->LastErrorCode());
+  EXPECT_EQ(0U, this->op_->LastErrorAddress());
 
   // Register set.
   // Do this first, to verify that subsequent calls reset the value.
@@ -84,7 +86,7 @@
   this->op_memory_.SetMemory(0, opcode_buffer);
 
   ASSERT_TRUE(this->op_->Eval(0, 8, DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_NONE, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_NONE, this->op_->LastErrorCode());
   ASSERT_FALSE(this->op_->is_register());
   ASSERT_EQ(8U, this->mem_->cur_offset());
   ASSERT_EQ(4U, this->op_->StackSize());
@@ -96,7 +98,7 @@
   // Infinite loop.
   this->op_memory_.SetMemory(0, std::vector<uint8_t>{0x2f, 0xfd, 0xff});
   ASSERT_FALSE(this->op_->Eval(0, 4, DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_TOO_MANY_ITERATIONS, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_TOO_MANY_ITERATIONS, this->op_->LastErrorCode());
   ASSERT_FALSE(this->op_->is_register());
   ASSERT_EQ(0U, this->op_->StackSize());
 }
@@ -111,7 +113,7 @@
 
   for (size_t i = 0; i < opcode_buffer.size(); i++) {
     ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-    ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->op_->last_error());
+    ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->op_->LastErrorCode());
     ASSERT_EQ(opcode_buffer[i], this->op_->cur_op());
   }
 }
@@ -122,7 +124,7 @@
 
   for (size_t i = 0; i < opcode_buffer.size(); i++) {
     ASSERT_FALSE(this->op_->Decode(2));
-    ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->op_->last_error());
+    ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->op_->LastErrorCode());
     ASSERT_EQ(opcode_buffer[i], this->op_->cur_op());
   }
 }
@@ -133,7 +135,7 @@
 
   for (size_t i = 0; i < opcode_buffer.size(); i++) {
     ASSERT_FALSE(this->op_->Decode(3));
-    ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->op_->last_error());
+    ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->op_->LastErrorCode());
     ASSERT_EQ(opcode_buffer[i], this->op_->cur_op());
   }
 }
@@ -178,7 +180,7 @@
 
   while (this->mem_->cur_offset() < opcode_buffer.size()) {
     ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-    ASSERT_EQ(DWARF_ERROR_NOT_IMPLEMENTED, this->op_->last_error());
+    ASSERT_EQ(DWARF_ERROR_NOT_IMPLEMENTED, this->op_->LastErrorCode());
   }
 }
 
@@ -216,7 +218,7 @@
   this->regular_memory_.SetMemory(0x2010, &value, sizeof(value));
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(1U, this->op_->StackSize());
@@ -226,7 +228,8 @@
   ASSERT_EQ(value, this->op_->StackAt(0));
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_MEMORY_INVALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_MEMORY_INVALID, this->op_->LastErrorCode());
+  ASSERT_EQ(0x12345678U, this->op_->LastErrorAddress());
 }
 
 TYPED_TEST_P(DwarfOpTest, op_deref_size) {
@@ -235,7 +238,7 @@
   this->regular_memory_.SetMemory(0x2010, &value, sizeof(value));
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   // Read all byte sizes up to the sizeof the type.
   for (size_t i = 1; i < sizeof(TypeParam); i++) {
@@ -252,17 +255,18 @@
   // Zero byte read.
   this->op_memory_.SetMemory(0, std::vector<uint8_t>{0x0a, 0x10, 0x20, 0x94, 0x00});
   ASSERT_FALSE(this->op_->Eval(0, 5, DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->op_->LastErrorCode());
 
   // Read too many bytes.
   this->op_memory_.SetMemory(0, std::vector<uint8_t>{0x0a, 0x10, 0x20, 0x94, sizeof(TypeParam) + 1});
   ASSERT_FALSE(this->op_->Eval(0, 5, DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->op_->LastErrorCode());
 
   // Force bad memory read.
   this->op_memory_.SetMemory(0, std::vector<uint8_t>{0x0a, 0x10, 0x40, 0x94, 0x01});
   ASSERT_FALSE(this->op_->Eval(0, 5, DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_MEMORY_INVALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_MEMORY_INVALID, this->op_->LastErrorCode());
+  EXPECT_EQ(0x4010U, this->op_->LastErrorAddress());
 }
 
 TYPED_TEST_P(DwarfOpTest, const_unsigned) {
@@ -529,7 +533,7 @@
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(0x12, this->op_->cur_op());
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(1U, this->op_->StackSize());
@@ -577,7 +581,7 @@
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(0x13, this->op_->cur_op());
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfOpTest, op_over) {
@@ -612,7 +616,7 @@
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(0x14, this->op_->cur_op());
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfOpTest, op_pick) {
@@ -654,7 +658,7 @@
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(0x15, this->op_->cur_op());
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfOpTest, op_swap) {
@@ -686,7 +690,7 @@
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(0x16, this->op_->cur_op());
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfOpTest, op_rot) {
@@ -703,19 +707,19 @@
   this->op_memory_.SetMemory(0, opcode_buffer);
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(1U, this->op_->StackSize());
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(2U, this->op_->StackSize());
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(3U, this->op_->StackSize());
@@ -753,7 +757,7 @@
   this->op_memory_.SetMemory(0, opcode_buffer);
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(1U, this->op_->StackSize());
@@ -805,13 +809,13 @@
   this->op_memory_.SetMemory(0, opcode_buffer);
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(1U, this->op_->StackSize());
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   // Two positive values.
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
@@ -854,7 +858,7 @@
   ASSERT_EQ(5U, this->op_->StackSize());
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->op_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfOpTest, op_div) {
@@ -871,13 +875,13 @@
   this->op_memory_.SetMemory(0, opcode_buffer);
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(1U, this->op_->StackSize());
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(2U, this->op_->StackSize());
@@ -902,13 +906,13 @@
   this->op_memory_.SetMemory(0, opcode_buffer);
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(1U, this->op_->StackSize());
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(2U, this->op_->StackSize());
@@ -935,13 +939,13 @@
   this->op_memory_.SetMemory(0, opcode_buffer);
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(1U, this->op_->StackSize());
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(2U, this->op_->StackSize());
@@ -957,7 +961,7 @@
   ASSERT_EQ(3U, this->op_->StackSize());
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->op_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfOpTest, op_mul) {
@@ -974,13 +978,13 @@
   this->op_memory_.SetMemory(0, opcode_buffer);
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(1U, this->op_->StackSize());
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(2U, this->op_->StackSize());
@@ -1003,7 +1007,7 @@
   this->op_memory_.SetMemory(0, opcode_buffer);
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(1U, this->op_->StackSize());
@@ -1034,7 +1038,7 @@
   this->op_memory_.SetMemory(0, opcode_buffer);
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(1U, this->op_->StackSize());
@@ -1067,13 +1071,13 @@
   this->op_memory_.SetMemory(0, opcode_buffer);
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(1U, this->op_->StackSize());
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(2U, this->op_->StackSize());
@@ -1098,13 +1102,13 @@
   this->op_memory_.SetMemory(0, opcode_buffer);
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(1U, this->op_->StackSize());
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(2U, this->op_->StackSize());
@@ -1125,7 +1129,7 @@
   this->op_memory_.SetMemory(0, opcode_buffer);
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(1U, this->op_->StackSize());
@@ -1150,13 +1154,13 @@
   this->op_memory_.SetMemory(0, opcode_buffer);
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(1U, this->op_->StackSize());
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(2U, this->op_->StackSize());
@@ -1181,13 +1185,13 @@
   this->op_memory_.SetMemory(0, opcode_buffer);
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(1U, this->op_->StackSize());
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(2U, this->op_->StackSize());
@@ -1216,13 +1220,13 @@
   this->op_memory_.SetMemory(0, opcode_buffer);
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(1U, this->op_->StackSize());
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(2U, this->op_->StackSize());
@@ -1247,13 +1251,13 @@
   this->op_memory_.SetMemory(0, opcode_buffer);
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(1U, this->op_->StackSize());
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
   ASSERT_EQ(2U, this->op_->StackSize());
@@ -1280,7 +1284,7 @@
   this->op_memory_.SetMemory(0, opcode_buffer);
 
   ASSERT_FALSE(this->op_->Decode(DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
   // Push on a non-zero value with a positive branch.
   ASSERT_TRUE(this->op_->Decode(DWARF_VERSION_MAX));
@@ -1342,12 +1346,12 @@
 
     ASSERT_FALSE(this->op_->Eval(0, 1, DWARF_VERSION_MAX));
     ASSERT_EQ(opcode, this->op_->cur_op());
-    ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+    ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
 
     ASSERT_FALSE(this->op_->Eval(1, 4, DWARF_VERSION_MAX));
     ASSERT_EQ(opcode, this->op_->cur_op());
     ASSERT_EQ(1U, this->op_->StackSize());
-    ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->last_error());
+    ASSERT_EQ(DWARF_ERROR_STACK_INDEX_NOT_VALID, this->op_->LastErrorCode());
   }
 }
 
@@ -1532,7 +1536,7 @@
 
   // Should fail since this references a non-existent register.
   ASSERT_FALSE(this->op_->Eval(2, 4, DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->op_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfOpTest, op_bregx) {
@@ -1560,7 +1564,7 @@
   ASSERT_EQ(0x90U, this->op_->StackAt(0));
 
   ASSERT_FALSE(this->op_->Eval(7, 12, DWARF_VERSION_MAX));
-  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->op_->last_error());
+  ASSERT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->op_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfOpTest, op_nop) {
diff --git a/libunwindstack/tests/DwarfSectionImplTest.cpp b/libunwindstack/tests/DwarfSectionImplTest.cpp
index dfd2ce0..7e10935 100644
--- a/libunwindstack/tests/DwarfSectionImplTest.cpp
+++ b/libunwindstack/tests/DwarfSectionImplTest.cpp
@@ -19,10 +19,10 @@
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
 
+#include <unwindstack/DwarfError.h>
 #include <unwindstack/DwarfSection.h>
 
 #include "DwarfEncoding.h"
-#include "DwarfError.h"
 
 #include "LogFake.h"
 #include "MemoryFake.h"
@@ -67,7 +67,7 @@
   }
   void TestClearCachedCieLocRegs() { this->cie_loc_regs_.clear(); }
 
-  void TestClearError() { this->last_error_ = DWARF_ERROR_NONE; }
+  void TestClearError() { this->last_error_.code = DWARF_ERROR_NONE; }
 };
 
 template <typename TypeParam>
@@ -102,7 +102,8 @@
   loc_regs[CFA_REG] = DwarfLocation{DWARF_LOCATION_EXPRESSION, {0x2, 0x5000}};
   bool finished;
   ASSERT_FALSE(this->section_->Eval(&cie, &this->memory_, loc_regs, &regs, &finished));
-  EXPECT_EQ(DWARF_ERROR_MEMORY_INVALID, this->section_->last_error());
+  EXPECT_EQ(DWARF_ERROR_MEMORY_INVALID, this->section_->LastErrorCode());
+  EXPECT_EQ(0x5000U, this->section_->LastErrorAddress());
 }
 
 TYPED_TEST_P(DwarfSectionImplTest, Eval_cfa_expr_no_stack) {
@@ -118,7 +119,7 @@
   loc_regs[CFA_REG] = DwarfLocation{DWARF_LOCATION_EXPRESSION, {0x2, 0x5000}};
   bool finished;
   ASSERT_FALSE(this->section_->Eval(&cie, &this->memory_, loc_regs, &regs, &finished));
-  EXPECT_EQ(DWARF_ERROR_ILLEGAL_STATE, this->section_->last_error());
+  EXPECT_EQ(DWARF_ERROR_ILLEGAL_STATE, this->section_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfSectionImplTest, Eval_cfa_expr) {
@@ -172,7 +173,7 @@
   loc_regs[CFA_REG] = DwarfLocation{DWARF_LOCATION_EXPRESSION, {0x2, 0x5000}};
   bool finished;
   ASSERT_FALSE(this->section_->Eval(&cie, &this->memory_, loc_regs, &regs, &finished));
-  EXPECT_EQ(DWARF_ERROR_NOT_IMPLEMENTED, this->section_->last_error());
+  EXPECT_EQ(DWARF_ERROR_NOT_IMPLEMENTED, this->section_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfSectionImplTest, Eval_bad_regs) {
@@ -182,7 +183,7 @@
 
   bool finished;
   ASSERT_FALSE(this->section_->Eval(&cie, &this->memory_, loc_regs, &regs, &finished));
-  EXPECT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->section_->last_error());
+  EXPECT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->section_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfSectionImplTest, Eval_no_cfa) {
@@ -192,7 +193,7 @@
 
   bool finished;
   ASSERT_FALSE(this->section_->Eval(&cie, &this->memory_, loc_regs, &regs, &finished));
-  EXPECT_EQ(DWARF_ERROR_CFA_NOT_DEFINED, this->section_->last_error());
+  EXPECT_EQ(DWARF_ERROR_CFA_NOT_DEFINED, this->section_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfSectionImplTest, Eval_cfa_bad) {
@@ -203,25 +204,25 @@
   loc_regs[CFA_REG] = DwarfLocation{DWARF_LOCATION_REGISTER, {20, 0}};
   bool finished;
   ASSERT_FALSE(this->section_->Eval(&cie, &this->memory_, loc_regs, &regs, &finished));
-  EXPECT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->section_->last_error());
+  EXPECT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->section_->LastErrorCode());
 
   this->section_->TestClearError();
   loc_regs.erase(CFA_REG);
   loc_regs[CFA_REG] = DwarfLocation{DWARF_LOCATION_INVALID, {0, 0}};
   ASSERT_FALSE(this->section_->Eval(&cie, &this->memory_, loc_regs, &regs, &finished));
-  EXPECT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->section_->last_error());
+  EXPECT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->section_->LastErrorCode());
 
   this->section_->TestClearError();
   loc_regs.erase(CFA_REG);
   loc_regs[CFA_REG] = DwarfLocation{DWARF_LOCATION_OFFSET, {0, 0}};
   ASSERT_FALSE(this->section_->Eval(&cie, &this->memory_, loc_regs, &regs, &finished));
-  EXPECT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->section_->last_error());
+  EXPECT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->section_->LastErrorCode());
 
   this->section_->TestClearError();
   loc_regs.erase(CFA_REG);
   loc_regs[CFA_REG] = DwarfLocation{DWARF_LOCATION_VAL_OFFSET, {0, 0}};
   ASSERT_FALSE(this->section_->Eval(&cie, &this->memory_, loc_regs, &regs, &finished));
-  EXPECT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->section_->last_error());
+  EXPECT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->section_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfSectionImplTest, Eval_cfa_register_prev) {
@@ -341,7 +342,7 @@
   loc_regs[1] = DwarfLocation{DWARF_LOCATION_REGISTER, {10, 0}};
   bool finished;
   ASSERT_FALSE(this->section_->Eval(&cie, &this->memory_, loc_regs, &regs, &finished));
-  EXPECT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->section_->last_error());
+  EXPECT_EQ(DWARF_ERROR_ILLEGAL_VALUE, this->section_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfSectionImplTest, Eval_different_reg_locations) {
@@ -489,10 +490,12 @@
 
 TYPED_TEST_P(DwarfSectionImplTest, GetCie_fail_should_not_cache) {
   ASSERT_TRUE(this->section_->GetCie(0x4000) == nullptr);
-  EXPECT_EQ(DWARF_ERROR_MEMORY_INVALID, this->section_->last_error());
+  EXPECT_EQ(DWARF_ERROR_MEMORY_INVALID, this->section_->LastErrorCode());
+  EXPECT_EQ(0x4000U, this->section_->LastErrorAddress());
   this->section_->TestClearError();
   ASSERT_TRUE(this->section_->GetCie(0x4000) == nullptr);
-  EXPECT_EQ(DWARF_ERROR_MEMORY_INVALID, this->section_->last_error());
+  EXPECT_EQ(DWARF_ERROR_MEMORY_INVALID, this->section_->LastErrorCode());
+  EXPECT_EQ(0x4000U, this->section_->LastErrorAddress());
 }
 
 TYPED_TEST_P(DwarfSectionImplTest, GetCie_32_version_check) {
@@ -518,24 +521,24 @@
   EXPECT_EQ(4U, cie->code_alignment_factor);
   EXPECT_EQ(8, cie->data_alignment_factor);
   EXPECT_EQ(0x20U, cie->return_address_register);
-  EXPECT_EQ(DWARF_ERROR_NONE, this->section_->last_error());
+  EXPECT_EQ(DWARF_ERROR_NONE, this->section_->LastErrorCode());
 
   this->section_->TestClearCachedCieEntry();
   // Set version to 0, 2, 5 and verify we fail.
   this->memory_.SetData8(0x5008, 0x0);
   this->section_->TestClearError();
   ASSERT_TRUE(this->section_->GetCie(0x5000) == nullptr);
-  EXPECT_EQ(DWARF_ERROR_UNSUPPORTED_VERSION, this->section_->last_error());
+  EXPECT_EQ(DWARF_ERROR_UNSUPPORTED_VERSION, this->section_->LastErrorCode());
 
   this->memory_.SetData8(0x5008, 0x2);
   this->section_->TestClearError();
   ASSERT_TRUE(this->section_->GetCie(0x5000) == nullptr);
-  EXPECT_EQ(DWARF_ERROR_UNSUPPORTED_VERSION, this->section_->last_error());
+  EXPECT_EQ(DWARF_ERROR_UNSUPPORTED_VERSION, this->section_->LastErrorCode());
 
   this->memory_.SetData8(0x5008, 0x5);
   this->section_->TestClearError();
   ASSERT_TRUE(this->section_->GetCie(0x5000) == nullptr);
-  EXPECT_EQ(DWARF_ERROR_UNSUPPORTED_VERSION, this->section_->last_error());
+  EXPECT_EQ(DWARF_ERROR_UNSUPPORTED_VERSION, this->section_->LastErrorCode());
 }
 
 TYPED_TEST_P(DwarfSectionImplTest, GetCie_negative_data_alignment_factor) {
@@ -681,10 +684,12 @@
 
 TYPED_TEST_P(DwarfSectionImplTest, GetFdeFromOffset_fail_should_not_cache) {
   ASSERT_TRUE(this->section_->GetFdeFromOffset(0x4000) == nullptr);
-  EXPECT_EQ(DWARF_ERROR_MEMORY_INVALID, this->section_->last_error());
+  EXPECT_EQ(DWARF_ERROR_MEMORY_INVALID, this->section_->LastErrorCode());
+  EXPECT_EQ(0x4000U, this->section_->LastErrorAddress());
   this->section_->TestClearError();
   ASSERT_TRUE(this->section_->GetFdeFromOffset(0x4000) == nullptr);
-  EXPECT_EQ(DWARF_ERROR_MEMORY_INVALID, this->section_->last_error());
+  EXPECT_EQ(DWARF_ERROR_MEMORY_INVALID, this->section_->LastErrorCode());
+  EXPECT_EQ(0x4000U, this->section_->LastErrorAddress());
 }
 
 TYPED_TEST_P(DwarfSectionImplTest, GetFdeFromOffset_32_no_augment) {
diff --git a/libunwindstack/tests/ElfFake.h b/libunwindstack/tests/ElfFake.h
index 099026c..e232986 100644
--- a/libunwindstack/tests/ElfFake.h
+++ b/libunwindstack/tests/ElfFake.h
@@ -87,6 +87,10 @@
     steps_.clear();
   }
 
+  void FakeSetErrorCode(ErrorCode code) { last_error_.code = code; }
+
+  void FakeSetErrorAddress(uint64_t address) { last_error_.address = address; }
+
  private:
   std::unordered_map<std::string, uint64_t> globals_;
 
diff --git a/libunwindstack/tests/ElfInterfaceArmTest.cpp b/libunwindstack/tests/ElfInterfaceArmTest.cpp
index e6763ab..31d6a63 100644
--- a/libunwindstack/tests/ElfInterfaceArmTest.cpp
+++ b/libunwindstack/tests/ElfInterfaceArmTest.cpp
@@ -303,6 +303,7 @@
   // FindEntry fails.
   bool finished;
   ASSERT_FALSE(interface.StepExidx(0x7000, 0, nullptr, nullptr, &finished));
+  EXPECT_EQ(ERROR_UNWIND_INFO, interface.LastErrorCode());
 
   // ExtractEntry should fail.
   interface.FakeSetStartOffset(0x1000);
@@ -316,14 +317,18 @@
   regs.set_sp(regs[ARM_REG_SP]);
   regs.set_pc(0x1234);
   ASSERT_FALSE(interface.StepExidx(0x7000, 0, &regs, &process_memory_, &finished));
+  EXPECT_EQ(ERROR_MEMORY_INVALID, interface.LastErrorCode());
+  EXPECT_EQ(0x1004U, interface.LastErrorAddress());
 
   // Eval should fail.
   memory_.SetData32(0x1004, 0x81000000);
   ASSERT_FALSE(interface.StepExidx(0x7000, 0, &regs, &process_memory_, &finished));
+  EXPECT_EQ(ERROR_UNWIND_INFO, interface.LastErrorCode());
 
   // Everything should pass.
   memory_.SetData32(0x1004, 0x80b0b0b0);
   ASSERT_TRUE(interface.StepExidx(0x7000, 0, &regs, &process_memory_, &finished));
+  EXPECT_EQ(ERROR_UNWIND_INFO, interface.LastErrorCode());
   ASSERT_FALSE(finished);
   ASSERT_EQ(0x1000U, regs.sp());
   ASSERT_EQ(0x1000U, regs[ARM_REG_SP]);
@@ -332,9 +337,11 @@
 
   // Load bias is non-zero.
   ASSERT_TRUE(interface.StepExidx(0x8000, 0x1000, &regs, &process_memory_, &finished));
+  EXPECT_EQ(ERROR_UNWIND_INFO, interface.LastErrorCode());
 
   // Pc too small.
   ASSERT_FALSE(interface.StepExidx(0x8000, 0x9000, &regs, &process_memory_, &finished));
+  EXPECT_EQ(ERROR_UNWIND_INFO, interface.LastErrorCode());
 }
 
 TEST_F(ElfInterfaceArmTest, StepExidx_pc_set) {
@@ -356,6 +363,7 @@
   // Everything should pass.
   bool finished;
   ASSERT_TRUE(interface.StepExidx(0x7000, 0, &regs, &process_memory_, &finished));
+  EXPECT_EQ(ERROR_NONE, interface.LastErrorCode());
   ASSERT_FALSE(finished);
   ASSERT_EQ(0x10004U, regs.sp());
   ASSERT_EQ(0x10004U, regs[ARM_REG_SP]);
@@ -379,6 +387,7 @@
 
   bool finished;
   ASSERT_TRUE(interface.StepExidx(0x7000, 0, &regs, &process_memory_, &finished));
+  EXPECT_EQ(ERROR_NONE, interface.LastErrorCode());
   ASSERT_TRUE(finished);
   ASSERT_EQ(0x10000U, regs.sp());
   ASSERT_EQ(0x10000U, regs[ARM_REG_SP]);
@@ -401,6 +410,7 @@
 
   bool finished;
   ASSERT_TRUE(interface.StepExidx(0x7000, 0, &regs, &process_memory_, &finished));
+  EXPECT_EQ(ERROR_NONE, interface.LastErrorCode());
   ASSERT_TRUE(finished);
   ASSERT_EQ(0x10000U, regs.sp());
   ASSERT_EQ(0x10000U, regs[ARM_REG_SP]);
@@ -427,6 +437,7 @@
 
   bool finished;
   ASSERT_TRUE(interface.StepExidx(0x7000, 0, &regs, &process_memory_, &finished));
+  EXPECT_EQ(ERROR_NONE, interface.LastErrorCode());
   ASSERT_TRUE(finished);
   ASSERT_EQ(0U, regs.pc());
 
@@ -439,6 +450,7 @@
   regs.set_pc(0x1234);
 
   ASSERT_TRUE(interface.StepExidx(0x7000, 0, &regs, &process_memory_, &finished));
+  EXPECT_EQ(ERROR_NONE, interface.LastErrorCode());
   ASSERT_TRUE(finished);
   ASSERT_EQ(0U, regs.pc());
 }
diff --git a/libunwindstack/tests/ElfTest.cpp b/libunwindstack/tests/ElfTest.cpp
index 7e6a62a..eb85033 100644
--- a/libunwindstack/tests/ElfTest.cpp
+++ b/libunwindstack/tests/ElfTest.cpp
@@ -581,4 +581,30 @@
   EXPECT_TRUE(elf.IsValidPc(0x1500));
 }
 
+TEST_F(ElfTest, error_code_not_valid) {
+  ElfFake elf(memory_);
+  elf.FakeSetValid(false);
+
+  ErrorData error{ERROR_MEMORY_INVALID, 0x100};
+  elf.GetLastError(&error);
+  EXPECT_EQ(ERROR_MEMORY_INVALID, error.code);
+  EXPECT_EQ(0x100U, error.address);
+}
+
+TEST_F(ElfTest, error_code_valid) {
+  ElfFake elf(memory_);
+  elf.FakeSetValid(true);
+  ElfInterfaceFake* interface = new ElfInterfaceFake(memory_);
+  elf.FakeSetInterface(interface);
+  interface->FakeSetErrorCode(ERROR_MEMORY_INVALID);
+  interface->FakeSetErrorAddress(0x1000);
+
+  ErrorData error{ERROR_NONE, 0};
+  elf.GetLastError(&error);
+  EXPECT_EQ(ERROR_MEMORY_INVALID, error.code);
+  EXPECT_EQ(0x1000U, error.address);
+  EXPECT_EQ(ERROR_MEMORY_INVALID, elf.GetLastErrorCode());
+  EXPECT_EQ(0x1000U, elf.GetLastErrorAddress());
+}
+
 }  // namespace unwindstack
diff --git a/libunwindstack/tests/UnwinderTest.cpp b/libunwindstack/tests/UnwinderTest.cpp
index cd46807..bf2c1d8 100644
--- a/libunwindstack/tests/UnwinderTest.cpp
+++ b/libunwindstack/tests/UnwinderTest.cpp
@@ -129,6 +129,7 @@
 
   Unwinder unwinder(64, &maps_, &regs_, process_memory_);
   unwinder.Unwind();
+  EXPECT_EQ(ERROR_NONE, unwinder.LastErrorCode());
 
   ASSERT_EQ(3U, unwinder.NumFrames());
 
@@ -184,6 +185,7 @@
 
   Unwinder unwinder(64, &maps_, &regs_, process_memory_);
   unwinder.Unwind();
+  EXPECT_EQ(ERROR_NONE, unwinder.LastErrorCode());
 
   ASSERT_EQ(1U, unwinder.NumFrames());
 
@@ -218,6 +220,7 @@
 
   Unwinder unwinder(64, &maps_, &regs_, process_memory_);
   unwinder.Unwind();
+  EXPECT_EQ(ERROR_NONE, unwinder.LastErrorCode());
 
   ASSERT_EQ(1U, unwinder.NumFrames());
 
@@ -248,6 +251,7 @@
 
   Unwinder unwinder(20, &maps_, &regs_, process_memory_);
   unwinder.Unwind();
+  EXPECT_EQ(ERROR_MAX_FRAMES_EXCEEDED, unwinder.LastErrorCode());
 
   ASSERT_EQ(20U, unwinder.NumFrames());
 
@@ -288,6 +292,7 @@
   Unwinder unwinder(64, &maps_, &regs_, process_memory_);
   std::vector<std::string> skip_libs{"libunwind.so", "libanother.so"};
   unwinder.Unwind(&skip_libs);
+  EXPECT_EQ(ERROR_NONE, unwinder.LastErrorCode());
 
   ASSERT_EQ(3U, unwinder.NumFrames());
 
@@ -346,6 +351,7 @@
 
   Unwinder unwinder(64, &maps_, &regs_, process_memory_);
   unwinder.Unwind();
+  EXPECT_EQ(ERROR_NONE, unwinder.LastErrorCode());
 
   ASSERT_EQ(2U, unwinder.NumFrames());
 
@@ -392,6 +398,7 @@
 
   Unwinder unwinder(64, &maps_, &regs_, process_memory_);
   unwinder.Unwind();
+  EXPECT_EQ(ERROR_NONE, unwinder.LastErrorCode());
 
   ASSERT_EQ(1U, unwinder.NumFrames());
 }
@@ -410,6 +417,7 @@
 
   Unwinder unwinder(64, &maps_, &regs_, process_memory_);
   unwinder.Unwind();
+  EXPECT_EQ(ERROR_NONE, unwinder.LastErrorCode());
 
   ASSERT_EQ(1U, unwinder.NumFrames());
 }
@@ -423,6 +431,7 @@
 
   Unwinder unwinder(64, &maps_, &regs_, process_memory_);
   unwinder.Unwind();
+  EXPECT_EQ(ERROR_INVALID_MAP, unwinder.LastErrorCode());
 
   ASSERT_EQ(1U, unwinder.NumFrames());
 
@@ -457,6 +466,7 @@
 
   Unwinder unwinder(64, &maps_, &regs_, process_memory_);
   unwinder.Unwind();
+  EXPECT_EQ(ERROR_NONE, unwinder.LastErrorCode());
 
   ASSERT_EQ(3U, unwinder.NumFrames());
 
@@ -517,6 +527,7 @@
 
   Unwinder unwinder(64, &maps_, &regs_, process_memory_);
   unwinder.Unwind();
+  EXPECT_EQ(ERROR_NONE, unwinder.LastErrorCode());
 
   ASSERT_EQ(1U, unwinder.NumFrames());
 
@@ -552,6 +563,7 @@
   Unwinder unwinder(64, &maps_, &regs_, process_memory_);
   std::vector<std::string> suffixes{"oat"};
   unwinder.Unwind(nullptr, &suffixes);
+  EXPECT_EQ(ERROR_NONE, unwinder.LastErrorCode());
 
   ASSERT_EQ(2U, unwinder.NumFrames());
   // Make sure the elf was not initialized.
@@ -607,6 +619,7 @@
 
   Unwinder unwinder(64, &maps_, &regs_, process_memory_);
   unwinder.Unwind();
+  EXPECT_EQ(ERROR_REPEATED_FRAME, unwinder.LastErrorCode());
 
   ASSERT_EQ(3U, unwinder.NumFrames());