[gjs] build: Hide Clang-only pragmas from GCC

[Philip Chimento <pchimento src gnome org>]

commit 689b881407c70adbad8cf28ad555f71b48ca687b
Author: Philip Chimento <philip endlessm com>
Date:   Tue Dec 20 18:21:03 2016 -0800

    build: Hide Clang-only pragmas from GCC
    
    These warnings aren't generated on GCC, so ignoring them produces a
    warning. Therefore we should only ignore them when compiling with Clang.
    
    (Unreviewed, fixes -Werror build.)

 gjs/jsapi-constructor-proxy.cpp |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)
---
diff --git a/gjs/jsapi-constructor-proxy.cpp b/gjs/jsapi-constructor-proxy.cpp
index 363a418..d0a795d 100644
--- a/gjs/jsapi-constructor-proxy.cpp
+++ b/gjs/jsapi-constructor-proxy.cpp
@@ -31,8 +31,10 @@
 
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Winvalid-offsetof"
-#pragma GCC diagnostic ignored "-Wmismatched-tags"
-#pragma GCC diagnostic ignored "-Winconsistent-missing-override"
+#ifdef __clang__
+#pragma clang diagnostic ignored "-Wmismatched-tags"
+#pragma clang diagnostic ignored "-Winconsistent-missing-override"
+#endif /* __clang__ */
 #include "jsproxy.h"
 #pragma GCC diagnostic pop