#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<bar>);
// 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) {}
}