[PATCHv2 5/6] jump label: detect %c support for ARM

From: Rabin Vincent
Date: Sat Jan 28 2012 - 08:37:19 EST


Some versions of ARM GCC which do support asm goto, have problems
handling the 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

Cc: Jason Baron <jbaron@xxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Rabin Vincent <rabin@xxxxxx>
---
scripts/gcc-goto.sh | 18 +++++++++++++++++-
1 files changed, 17 insertions(+), 1 deletions(-)

diff --git a/scripts/gcc-goto.sh b/scripts/gcc-goto.sh
index 98cffcb..9b744de 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@xxxxxxxxxx>

-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 ("@ %c0" :: "i" (&tp.state));
+#endif
+
+entry:
+ asm goto ("" :::: entry);
+ return 0;
+}
+END
--
1.7.8.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/