stage1: fix gcc 9.1.0 compiler error on archlinux

Author: mikdusan

src/zig_clang_cc1_main.cpp

@@ -12,6 +12,11 @@
 //
 //===----------------------------------------------------------------------===//
 
+#if __GNUC__ >= 9
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Winit-list-lifetime"
+#endif
+
 #include "clang/Basic/Stack.h"
 #include "clang/Basic/TargetOptions.h"
 #include "clang/CodeGen/ObjectFilePCHContainerOperations.h"