Suppress 'taking address of label non-standard' GCC/Clang pedantic warning

* mark.c [WRAP_MARK_SOME && __GNUC__ && (MSWIN32 || MSWINCE)]
(GC_mark_some): Use pragma "GCC diagnostic ignored" to temporarily
suppress "taking the address of a label is non-standard" (or
"use of GNU address-of-label extension" in case of Clang) warning for
"&&handle_ex" expression.

diff --git a/mark.c b/mark.c
index b83ad91..6a04973 100644 (file)
--- a/mark.c
+++ b/mark.c
@@ -510,7 +510,22 @@ static void alloc_mark_stack(size_t);
 
       ext_ex_regn er;
 
-      er.alt_path = &&handle_ex;
+#     if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 7) \
+         || __clang_major__ > 3 \
+         || (__clang_major__ == 3 && __clang_minor__ >= 6)
+#       pragma GCC diagnostic push
+        /* Suppress "taking the address of label is non-standard" warning. */
+#       if defined(__clang__)
+#         pragma GCC diagnostic ignored "-Wpedantic"
+#       else
+          /* GCC before ~4.8 does not accept "-Wpedanic" quietly. */
+#         pragma GCC diagnostic ignored "-pedantic"
+#       endif
+        er.alt_path = &&handle_ex;
+#       pragma GCC diagnostic pop
+#     else /* pragma diagnostic is not supported */
+        er.alt_path = &&handle_ex;
+#     endif
       er.ex_reg.handler = mark_ex_handler;
       __asm__ __volatile__ ("movl %%fs:0, %0" : "=r" (er.ex_reg.prev));
       __asm__ __volatile__ ("movl %0, %%fs:0" : : "r" (&er));