merge in mnc-release history after reset to mnc-dev
diff --git a/libc/arch-arm/arm.mk b/libc/arch-arm/arm.mk
index 6ef81bb..d72a160 100644
--- a/libc/arch-arm/arm.mk
+++ b/libc/arch-arm/arm.mk
@@ -39,7 +39,6 @@
     arch-arm/bionic/__bionic_clone.S \
     arch-arm/bionic/_exit_with_stack_teardown.S \
     arch-arm/bionic/libgcc_compat.c \
-    arch-arm/bionic/libgcc_protect_unwind.c \
     arch-arm/bionic/__restore.S \
     arch-arm/bionic/setjmp.S \
     arch-arm/bionic/syscall.S \
diff --git a/libc/arch-arm/bionic/libgcc_protect_unwind.c b/libc/arch-arm/bionic/libgcc_protect_unwind.c
deleted file mode 100644
index 6d758fc..0000000
--- a/libc/arch-arm/bionic/libgcc_protect_unwind.c
+++ /dev/null
@@ -1,93 +0,0 @@
-/*
- * Copyright (C) 2015 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.
- */
-
-// TODO: This file should go away once unwinder migration to libc++.so is complete.
-
-extern char _Unwind_Backtrace __attribute((visibility("protected")));
-extern char __gnu_Unwind_Find_exidx __attribute((visibility("protected")));
-extern char __gnu_Unwind_Restore_VFP_D __attribute((visibility("protected")));
-extern char __gnu_Unwind_Restore_VFP __attribute((visibility("protected")));
-extern char __gnu_Unwind_Restore_VFP_D_16_to_31 __attribute((visibility("protected")));
-extern char __gnu_Unwind_Restore_WMMXD __attribute((visibility("protected")));
-extern char __gnu_Unwind_Restore_WMMXC __attribute((visibility("protected")));
-extern char _Unwind_GetCFA __attribute((visibility("protected")));
-extern char __gnu_Unwind_RaiseException __attribute((visibility("protected")));
-extern char __gnu_Unwind_ForcedUnwind __attribute((visibility("protected")));
-extern char __gnu_Unwind_Resume __attribute((visibility("protected")));
-extern char __gnu_Unwind_Resume_or_Rethrow __attribute((visibility("protected")));
-extern char _Unwind_Complete __attribute((visibility("protected")));
-extern char _Unwind_DeleteException __attribute((visibility("protected")));
-extern char _Unwind_VRS_Get __attribute((visibility("protected")));
-extern char _Unwind_VRS_Set __attribute((visibility("protected")));
-extern char __gnu_Unwind_Backtrace __attribute((visibility("protected")));
-extern char _Unwind_VRS_Pop __attribute((visibility("protected")));
-extern char __gnu_Unwind_Save_VFP_D __attribute((visibility("protected")));
-extern char __gnu_Unwind_Save_VFP __attribute((visibility("protected")));
-extern char __gnu_Unwind_Save_VFP_D_16_to_31 __attribute((visibility("protected")));
-extern char __gnu_Unwind_Save_WMMXD __attribute((visibility("protected")));
-extern char __gnu_Unwind_Save_WMMXC __attribute((visibility("protected")));
-extern char ___Unwind_RaiseException __attribute((visibility("protected")));
-extern char _Unwind_RaiseException __attribute((visibility("protected")));
-extern char ___Unwind_Resume __attribute((visibility("protected")));
-extern char _Unwind_Resume __attribute((visibility("protected")));
-extern char ___Unwind_Resume_or_Rethrow __attribute((visibility("protected")));
-extern char _Unwind_Resume_or_Rethrow __attribute((visibility("protected")));
-extern char ___Unwind_ForcedUnwind __attribute((visibility("protected")));
-extern char _Unwind_ForcedUnwind __attribute((visibility("protected")));
-extern char ___Unwind_Backtrace __attribute((visibility("protected")));
-extern char _Unwind_GetRegionStart __attribute((visibility("protected")));
-extern char _Unwind_GetLanguageSpecificData __attribute((visibility("protected")));
-extern char _Unwind_GetDataRelBase __attribute((visibility("protected")));
-extern char _Unwind_GetTextRelBase __attribute((visibility("protected")));
-
-void* __bionic_libgcc_unwind_symbols[] = {
-    &_Unwind_Backtrace,
-    &__gnu_Unwind_Find_exidx,
-    &__gnu_Unwind_Restore_VFP_D,
-    &__gnu_Unwind_Restore_VFP,
-    &__gnu_Unwind_Restore_VFP_D_16_to_31,
-    &__gnu_Unwind_Restore_WMMXD,
-    &__gnu_Unwind_Restore_WMMXC,
-    &_Unwind_GetCFA,
-    &__gnu_Unwind_RaiseException,
-    &__gnu_Unwind_ForcedUnwind,
-    &__gnu_Unwind_Resume,
-    &__gnu_Unwind_Resume_or_Rethrow,
-    &_Unwind_Complete,
-    &_Unwind_DeleteException,
-    &_Unwind_VRS_Get,
-    &_Unwind_VRS_Set,
-    &__gnu_Unwind_Backtrace,
-    &_Unwind_VRS_Pop,
-    &__gnu_Unwind_Save_VFP_D,
-    &__gnu_Unwind_Save_VFP,
-    &__gnu_Unwind_Save_VFP_D_16_to_31,
-    &__gnu_Unwind_Save_WMMXD,
-    &__gnu_Unwind_Save_WMMXC,
-    &___Unwind_RaiseException,
-    &_Unwind_RaiseException,
-    &___Unwind_Resume,
-    &_Unwind_Resume,
-    &___Unwind_Resume_or_Rethrow,
-    &_Unwind_Resume_or_Rethrow,
-    &___Unwind_ForcedUnwind,
-    &_Unwind_ForcedUnwind,
-    &___Unwind_Backtrace,
-    &_Unwind_GetRegionStart,
-    &_Unwind_GetLanguageSpecificData,
-    &_Unwind_GetDataRelBase,
-    &_Unwind_GetTextRelBase,
-};
diff --git a/libc/bionic/debug_mapinfo.cpp b/libc/bionic/debug_mapinfo.cpp
index 698ab6b..de72cb2 100644
--- a/libc/bionic/debug_mapinfo.cpp
+++ b/libc/bionic/debug_mapinfo.cpp
@@ -27,6 +27,7 @@
  */
 
 #include <ctype.h>
+#include <elf.h>
 #include <inttypes.h>
 #include <stdio.h>
 #include <string.h>
@@ -35,14 +36,22 @@
 #include "debug_mapinfo.h"
 #include "malloc_debug_disable.h"
 
+#if defined(__LP64__)
+#define Elf_W(x) Elf64_##x
+#else
+#define Elf_W(x) Elf32_##x
+#endif
+
 // Format of /proc/<PID>/maps:
 //   6f000000-6f01e000 rwxp 00000000 00:0c 16389419   /system/lib/libcomposer.so
 static mapinfo_t* parse_maps_line(char* line) {
   uintptr_t start;
   uintptr_t end;
+  uintptr_t offset;
+  char permissions[4];
   int name_pos;
-  if (sscanf(line, "%" PRIxPTR "-%" PRIxPTR " %*4s %*x %*x:%*x %*d%n", &start,
-             &end, &name_pos) < 2) {
+  if (sscanf(line, "%" PRIxPTR "-%" PRIxPTR " %4s %" PRIxPTR " %*x:%*x %*d%n", &start,
+             &end, permissions, &offset, &name_pos) < 2) {
     return NULL;
   }
 
@@ -59,6 +68,14 @@
   if (mi) {
     mi->start = start;
     mi->end = end;
+    mi->offset = offset;
+    if (permissions[0] != 'r') {
+      // Any unreadable map will just get a zero load base.
+      mi->load_base = 0;
+      mi->load_base_read = true;
+    } else {
+      mi->load_base_read = false;
+    }
     memcpy(mi->name, name, name_len);
     mi->name[name_len] = '\0';
   }
@@ -95,11 +112,58 @@
   }
 }
 
+template<typename T>
+static inline bool get_val(mapinfo_t* mi, uintptr_t addr, T* store) {
+  if (addr < mi->start || addr + sizeof(T) > mi->end) {
+    return false;
+  }
+  // Make sure the address is aligned properly.
+  if (addr & (sizeof(T)-1)) {
+    return false;
+  }
+  *store = *reinterpret_cast<T*>(addr);
+  return true;
+}
+
+__LIBC_HIDDEN__ void mapinfo_read_loadbase(mapinfo_t* mi) {
+  mi->load_base = 0;
+  mi->load_base_read = true;
+  uintptr_t addr = mi->start;
+  Elf_W(Ehdr) ehdr;
+  if (!get_val<Elf_W(Half)>(mi, addr + offsetof(Elf_W(Ehdr), e_phnum), &ehdr.e_phnum)) {
+    return;
+  }
+  if (!get_val<Elf_W(Off)>(mi, addr + offsetof(Elf_W(Ehdr), e_phoff), &ehdr.e_phoff)) {
+    return;
+  }
+  addr += ehdr.e_phoff;
+  for (size_t i = 0; i < ehdr.e_phnum; i++) {
+    Elf_W(Phdr) phdr;
+    if (!get_val<Elf_W(Word)>(mi, addr + offsetof(Elf_W(Phdr), p_type), &phdr.p_type)) {
+      return;
+    }
+    if (!get_val<Elf_W(Off)>(mi, addr + offsetof(Elf_W(Phdr), p_offset), &phdr.p_offset)) {
+      return;
+    }
+    if (phdr.p_type == PT_LOAD && phdr.p_offset == mi->offset) {
+      if (!get_val<Elf_W(Addr)>(mi, addr + offsetof(Elf_W(Phdr), p_vaddr), &phdr.p_vaddr)) {
+        return;
+      }
+      mi->load_base = phdr.p_vaddr;
+      return;
+    }
+    addr += sizeof(phdr);
+  }
+}
+
 // Find the containing map info for the PC.
 __LIBC_HIDDEN__ const mapinfo_t* mapinfo_find(mapinfo_t* mi, uintptr_t pc, uintptr_t* rel_pc) {
   for (; mi != NULL; mi = mi->next) {
     if ((pc >= mi->start) && (pc < mi->end)) {
-      *rel_pc = pc - mi->start;
+      if (!mi->load_base_read) {
+        mapinfo_read_loadbase(mi);
+      }
+      *rel_pc = pc - mi->start + mi->load_base;
       return mi;
     }
   }
diff --git a/libc/bionic/debug_mapinfo.h b/libc/bionic/debug_mapinfo.h
index 926b377..af7d05d 100644
--- a/libc/bionic/debug_mapinfo.h
+++ b/libc/bionic/debug_mapinfo.h
@@ -35,6 +35,9 @@
   struct mapinfo_t* next;
   uintptr_t start;
   uintptr_t end;
+  uintptr_t offset;
+  uintptr_t load_base;
+  bool load_base_read;
   char name[];
 };
 
diff --git a/tests/Android.mk b/tests/Android.mk
index 84d3426..cd60668 100644
--- a/tests/Android.mk
+++ b/tests/Android.mk
@@ -402,7 +402,7 @@
 
 LOCAL_CXX = $(LOCAL_PATH)/file-check-cxx \
     $(HOST_OUT_EXECUTABLES)/FileCheck \
-    $($(LOCAL_2ND_ARCH_VAR_PREFIX)CXX_BARE) \
+    $($(LOCAL_2ND_ARCH_VAR_PREFIX)TARGET_CXX) \
     GCC \
 
 LOCAL_CLANG := false