diff --git a/clang/include/clang/Driver/XRayArgs.h b/clang/include/clang/Driver/XRayArgs.h
index 4c18fecd276385..6ed99a127669bb 100644
--- a/clang/include/clang/Driver/XRayArgs.h
+++ b/clang/include/clang/Driver/XRayArgs.h
@@ -33,7 +33,7 @@ class XRayArgs {
   bool XRayIgnoreLoops = false;
   bool XRayFunctionIndex;
   int XRayFunctionGroups = 1;
-  int XRaySelectedFunctionGroup;
+  int XRaySelectedFunctionGroup = 0;
 
 public:
   /// Parses the XRay arguments from an argument list.