[m-rev.] diff: fix GCC labels with GCC 4.9 on x86_64

[Julien Fischer]

Branches 14.01, master

---------------------------

Fix GCC labels with GCC 4.9 on x86_64.

configure.ac:
     Disable GCC's -ftree-dominator-opts optimization when using
     GCC 4.9 on the x86_64 and x86.  As with GCC 4.8, its use seems
     incompatible with our use of GCC labels.

diff --git a/configure.ac b/configure.ac
index da28e43..78159b6 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2553,11 +2553,12 @@ case "$ac_cv_prog_gcc" in yes)
              CFLAGS_FOR_GOTOS="$CFLAGS_FOR_GOTOS -fomit-frame-pointer"
              ;;
          i*86-*|x86_64*)
-            # On x86-64 with GCC 4.8, gcc labels do not work correctly with
-            # -ftree-dominator-opts -- we disable it for x86 in this case too.
+            # On x86-64 with GCC 4.8 and 4.9, gcc labels do not work correctly
+            # with -ftree-dominator-opts -- we disable it for x86 in this case
+            # too.
              #
              case "$C_COMPILER_TYPE" in
-                gcc_4_8_*)
+                gcc_4_8_*|gcc_4_9_*)
                    CFLAGS_FOR_GOTOS="$CFLAGS_FOR_GOTOS -fno-tree-dominator-opts"
                  ;;
              esac