diff --git a/llvm/include/llvm/Support/Debug.h b/llvm/include/llvm/Support/Debug.h
index 23c54ac9bb4b1..9eef747d7496d 100644
--- a/llvm/include/llvm/Support/Debug.h
+++ b/llvm/include/llvm/Support/Debug.h
@@ -28,6 +28,8 @@
 #ifndef LLVM_SUPPORT_DEBUG_H
 #define LLVM_SUPPORT_DEBUG_H
 
+#include "llvm/Support/Compiler.h"
+
 namespace llvm {
 
 class raw_ostream;
@@ -94,7 +96,7 @@ extern bool EnableDebugBuffering;
 /// dbgs() - This returns a reference to a raw_ostream for debugging
 /// messages.  If debugging is disabled it returns errs().  Use it
 /// like: dbgs() << "foo" << "bar";
-raw_ostream &dbgs();
+LLVM_ABI raw_ostream &dbgs();
 
 // DEBUG macro - This macro should be used by passes to emit debug information.
 // If the '-debug' option is specified on the commandline, and if this is a