commit 0e252e38ef84e42cc0b6d0e6b0f0894f6867e5a7
author Alex Langford <apl@fb.com> Tue Jul 30 22:12:34 2019 +0000
committer Alex Langford <apl@fb.com> Tue Jul 30 22:12:34 2019 +0000
tree e74b7e4f611ee1a334968d8cedd4c9f3cb921269
parent d56dc1d926b9ee2317f3766d21700bdc77dd84f6

[Symbol] Use llvm::Expected when getting TypeSystems

Summary:
This commit achieves the following:
- Functions used to return a `TypeSystem *` return an
  `llvm::Expected<TypeSystem *>` now. This means that the result of a call
  is always checked, forcing clients to move more carefully.
- `TypeSystemMap::GetTypeSystemForLanguage` will either return an Error or a
  non-null pointer to a TypeSystem.

Reviewers: JDevlieghere, davide, compnerd

Subscribers: jdoerfert, lldb-commits

Differential Revision: https://reviews.llvm.org/D65122

llvm-svn: 367360

lldb/source/Plugins/Language/CPlusPlus/BlockPointer.cpp

diff --git a/lldb/source/Plugins/Language/CPlusPlus/BlockPointer.cpp b/lldb/source/Plugins/Language/CPlusPlus/BlockPointer.cpp
index 87b5b59..5cfd978 100644
--- a/lldb/source/Plugins/Language/CPlusPlus/BlockPointer.cpp
+++ b/lldb/source/Plugins/Language/CPlusPlus/BlockPointer.cpp
@@ -17,6 +17,7 @@
 #include "lldb/Target/Target.h"
 
 #include "lldb/Utility/LLDBAssert.h"
+#include "lldb/Utility/Log.h"
 
 using namespace lldb;
 using namespace lldb_private;
@@ -39,16 +40,17 @@
       return;
     }
 
-    Status err;
-    TypeSystem *type_system = target_sp->GetScratchTypeSystemForLanguage(
-        &err, lldb::eLanguageTypeC_plus_plus);
-
-    if (!err.Success() || !type_system) {
+    auto type_system_or_err = target_sp->GetScratchTypeSystemForLanguage(
+        lldb::eLanguageTypeC_plus_plus);
+    if (auto err = type_system_or_err.takeError()) {
+      LLDB_LOG_ERROR(
+          lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DATAFORMATTERS),
+          std::move(err), "Failed to get scratch ClangASTContext");
       return;
     }
 
     ClangASTContext *clang_ast_context =
-        llvm::dyn_cast<ClangASTContext>(type_system);
+        llvm::dyn_cast<ClangASTContext>(&type_system_or_err.get());
 
     if (!clang_ast_context) {
       return;

lldb/source/Plugins/Language/ObjC/CoreMedia.cpp

diff --git a/lldb/source/Plugins/Language/ObjC/CoreMedia.cpp b/lldb/source/Plugins/Language/ObjC/CoreMedia.cpp
index d19290e..247429d 100644
--- a/lldb/source/Plugins/Language/ObjC/CoreMedia.cpp
+++ b/lldb/source/Plugins/Language/ObjC/CoreMedia.cpp
@@ -10,6 +10,7 @@
 #include "CoreMedia.h"
 
 #include "lldb/Utility/Flags.h"
+#include "lldb/Utility/Log.h"
 
 #include "lldb/Symbol/TypeSystem.h"
 #include "lldb/Target/Target.h"
@@ -25,18 +26,21 @@
   if (!type.IsValid())
     return false;
 
-  TypeSystem *type_system =
+  auto type_system_or_err =
       valobj.GetExecutionContextRef()
           .GetTargetSP()
-          ->GetScratchTypeSystemForLanguage(nullptr, lldb::eLanguageTypeC);
-  if (!type_system)
+          ->GetScratchTypeSystemForLanguage(lldb::eLanguageTypeC);
+  if (auto err = type_system_or_err.takeError()) {
+    LLDB_LOG_ERROR(
+        lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DATAFORMATTERS),
+        std::move(err), "Failed to get scratch type system");
     return false;
-
+  }
   // fetch children by offset to compensate for potential lack of debug info
-  auto int64_ty =
-      type_system->GetBuiltinTypeForEncodingAndBitSize(eEncodingSint, 64);
-  auto int32_ty =
-      type_system->GetBuiltinTypeForEncodingAndBitSize(eEncodingSint, 32);
+  auto int64_ty = type_system_or_err->GetBuiltinTypeForEncodingAndBitSize(
+      eEncodingSint, 64);
+  auto int32_ty = type_system_or_err->GetBuiltinTypeForEncodingAndBitSize(
+      eEncodingSint, 32);
 
   auto value_sp(valobj.GetSyntheticChildAtOffset(0, int64_ty, true));
   auto timescale_sp(valobj.GetSyntheticChildAtOffset(8, int32_ty, true));