From ec381a4183f70122305f810c6b11b8f0e3bf83c0 Mon Sep 17 00:00:00 2001 From: Nick Lewycky Date: Tue, 15 Nov 2011 00:14:04 +0000 Subject: [PATCH] Fix linking for some users who already have tsan enabled code and are trying to link it against llvm code, by making our definitions weak. "Some users." git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144596 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/llvm/Support/Compiler.h | 7 +++++++ lib/Support/Valgrind.cpp | 12 ++++++------ 2 files changed, 13 insertions(+), 6 deletions(-) diff --git a/include/llvm/Support/Compiler.h b/include/llvm/Support/Compiler.h index cd2e4eb997e..14b55c147fe 100644 --- a/include/llvm/Support/Compiler.h +++ b/include/llvm/Support/Compiler.h @@ -61,12 +61,19 @@ #define LLVM_ATTRIBUTE_READONLY #endif +#if (__GNUC__ >= 4) +#define LLVM_ATTRIBUTE_WEAK __attribute__((__weak__)) +#else +#define LLVM_ATTRIBUTE_WEAK +#endif + #if (__GNUC__ >= 4) #define BUILTIN_EXPECT(EXPR, VALUE) __builtin_expect((EXPR), (VALUE)) #else #define BUILTIN_EXPECT(EXPR, VALUE) (EXPR) #endif + // C++ doesn't support 'extern template' of template specializations. GCC does, // but requires __extension__ before it. In the header, use this: // EXTERN_TEMPLATE_INSTANTIATION(class foo); diff --git a/lib/Support/Valgrind.cpp b/lib/Support/Valgrind.cpp index 078d705183d..46d93a26ef6 100644 --- a/lib/Support/Valgrind.cpp +++ b/lib/Support/Valgrind.cpp @@ -56,10 +56,10 @@ void llvm::sys::ValgrindDiscardTranslations(const void *Addr, size_t Len) { // These functions require no implementation, tsan just looks at the arguments // they're called with. extern "C" { -void AnnotateHappensBefore(const char *file, int line, - const volatile void *cv) {} -void AnnotateHappensAfter(const char *file, int line, - const volatile void *cv) {} -void AnnotateIgnoreWritesBegin(const char *file, int line) {} -void AnnotateIgnoreWritesEnd(const char *file, int line) {} +LLVM_ATTRIBUTE_WEAK void AnnotateHappensBefore(const char *file, int line, + const volatile void *cv) {} +LLVM_ATTRIBUTE_WEAK void AnnotateHappensAfter(const char *file, int line, + const volatile void *cv) {} +LLVM_ATTRIBUTE_WEAK void AnnotateIgnoreWritesBegin(const char *file, int line){} +LLVM_ATTRIBUTE_WEAK void AnnotateIgnoreWritesEnd(const char *file, int line) {} }