[llvm] r255092 - Fix the order of destructors in LibLTOCodeGenerator

[Steven Wu via llvm-commits]

Author: steven_wu
Date: Tue Dec  8 21:37:51 2015
New Revision: 255092

URL: http://llvm.org/viewvc/llvm-project?rev=255092&view=rev
Log:
Fix the order of destructors in LibLTOCodeGenerator

Summary:
The order of destructors in LTOCodeGenerator gets changed in r254696.
It is possible for LTOCodeGenerator to have a MergedModule created in
the OwnedContext, in which case the module must be destructed before
the context.

Reviewers: rafael, dexonsmith

Subscribers: llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D15346

Modified:
    llvm/trunk/include/llvm/LTO/LTOCodeGenerator.h
    llvm/trunk/tools/lto/lto.cpp

Modified: llvm/trunk/include/llvm/LTO/LTOCodeGenerator.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/LTO/LTOCodeGenerator.h?rev=255092&r1=255091&r2=255092&view=diff
==============================================================================
--- llvm/trunk/include/llvm/LTO/LTOCodeGenerator.h (original)
+++ llvm/trunk/include/llvm/LTO/LTOCodeGenerator.h Tue Dec  8 21:37:51 2015
@@ -148,6 +148,8 @@ struct LTOCodeGenerator {
 
   LLVMContext &getContext() { return Context; }
 
+  void resetMergedModule() { MergedModule.reset(); }
+
 private:
   void initializeLTOPasses();
 

Modified: llvm/trunk/tools/lto/lto.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/lto/lto.cpp?rev=255092&r1=255091&r2=255092&view=diff
==============================================================================
--- llvm/trunk/tools/lto/lto.cpp (original)
+++ llvm/trunk/tools/lto/lto.cpp Tue Dec  8 21:37:51 2015
@@ -124,6 +124,10 @@ struct LibLTOCodeGenerator : LTOCodeGene
       : LTOCodeGenerator(*Context), OwnedContext(std::move(Context)) {
     setDiagnosticHandler(handleLibLTODiagnostic, nullptr); }
 
+  // Reset the module first in case MergedModule is created in OwnedContext.
+  // Module must be destructed before its context gets destructed.
+  ~LibLTOCodeGenerator() { resetMergedModule(); }
+
   std::unique_ptr<MemoryBuffer> NativeObjectFile;
   std::unique_ptr<LLVMContext> OwnedContext;
 };