ARM: 7333/2: jump label: detect %c support for ARM

Some versions of ARM GCC which do support asm goto, do not support
the %c specifier.  Since we need the %c to support jump labels
on ARM, detect that too in the asm goto detection script to avoid
build errors with these versions.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48637

Acked-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 17 insertions, 1 deletions

diff --git a/scripts/gcc-goto.sh b/scripts/gcc-goto.sh
index 98cffcb941e..a2af2e88daf 100644
--- a/scripts/gcc-goto.sh
+++ b/scripts/gcc-goto.sh
@@ -2,4 +2,20 @@
 # Test for gcc 'asm goto' support
 # Copyright (C) 2010, Jason Baron <jbaron@redhat.com>
 
-echo "int main(void) { entry: asm goto (\"\"::::entry); return 0; }" | $@ -x c - -c -o /dev/null >/dev/null 2>&1 && echo "y"
+cat << "END" | $@ -x c - -c -o /dev/null >/dev/null 2>&1 && echo "y"
+int main(void)
+{
+#ifdef __arm__
+        /*
+         * Not related to asm goto, but used by jump label
+         * and broken on some ARM GCC versions (see GCC Bug 48637).
+         */
+        static struct { int dummy; int state; } tp;
+        asm (".long %c0" :: "i" (&tp.state));
+#endif
+
+entry:
+        asm goto ("" :::: entry);
+        return 0;
+}
+END