diff --git a/llvm/include/llvm/Target/TargetOptions.h b/llvm/include/llvm/Target/TargetOptions.h
--- a/llvm/include/llvm/Target/TargetOptions.h
+++ b/llvm/include/llvm/Target/TargetOptions.h
@@ -332,7 +332,7 @@
     unsigned XRayOmitFunctionIndex : 1;
 
     /// Stack protector guard offset to use.
-    unsigned StackProtectorGuardOffset : 32;
+    unsigned StackProtectorGuardOffset = -1U;
 
     /// Stack protector guard mode to use, e.g. tls, global.
     StackProtectorGuards StackProtectorGuard =