X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FSupport%2FValgrind.cpp;h=2c6d6aaadfff9e2a5c886a1efc4f69d044eca187;hb=dee5e2cf7fa5cfc9c9407d66dae9169586041a51;hp=078d705183d05b89fe440fc1adf634104f678dec;hpb=4d0a9ff36574da0c042e9bd3ae816301b392ac41;p=oota-llvm.git

diff --git a/lib/Support/Valgrind.cpp b/lib/Support/Valgrind.cpp
index 078d705183d..2c6d6aaadff 100644
--- a/lib/Support/Valgrind.cpp
+++ b/lib/Support/Valgrind.cpp
@@ -53,13 +53,23 @@ void llvm::sys::ValgrindDiscardTranslations(const void *Addr, size_t Len) {
 
 #endif  // !HAVE_VALGRIND_VALGRIND_H
 
+#if LLVM_ENABLE_THREADS != 0 && !defined(NDEBUG)
 // These functions require no implementation, tsan just looks at the arguments
-// they're called with.
+// they're called with. However, they are required to be weak as some other
+// application or library may already be providing these definitions for the
+// same reason we are.
 extern "C" {
+LLVM_ATTRIBUTE_WEAK void AnnotateHappensAfter(const char *file, int line,
+                                              const volatile void *cv);
+void AnnotateHappensAfter(const char *file, int line, const volatile void *cv) {
+}
+LLVM_ATTRIBUTE_WEAK void AnnotateHappensBefore(const char *file, int line,
+                                               const volatile void *cv);
 void AnnotateHappensBefore(const char *file, int line,
                            const volatile void *cv) {}
-void AnnotateHappensAfter(const char *file, int line,
-                          const volatile void *cv) {}
+LLVM_ATTRIBUTE_WEAK void AnnotateIgnoreWritesBegin(const char *file, int line);
 void AnnotateIgnoreWritesBegin(const char *file, int line) {}
+LLVM_ATTRIBUTE_WEAK void AnnotateIgnoreWritesEnd(const char *file, int line);
 void AnnotateIgnoreWritesEnd(const char *file, int line) {}
 }
+#endif