arm: work around assembler bug
Disable sibling call optimization based on binutils version. This is
to work around a bug in the assember in binutils versions < 2.22.
Branches to weak symbols can be incorrectly optimized in thumb mode to
a short branch (b.n instruction) that won't reach when the symbol gets
preempted.
http://sourceware.org/bugzilla/show_bug.cgi?id=12532
Signed-off-by: Allen Martin <amartin@nvidia.com>
Acked-by: Tom Rini <trini@ti.com>
diff --git a/arch/arm/config.mk b/arch/arm/config.mk
index 3f4453a..24b9d7c 100644
--- a/arch/arm/config.mk
+++ b/arch/arm/config.mk
@@ -87,3 +87,21 @@
ifndef CONFIG_NAND_SPL
LDFLAGS_u-boot += -pie
endif
+
+#
+# FIXME: binutils versions < 2.22 have a bug in the assembler where
+# branches to weak symbols can be incorrectly optimized in thumb mode
+# to a short branch (b.n instruction) that won't reach when the symbol
+# gets preempted
+#
+# http://sourceware.org/bugzilla/show_bug.cgi?id=12532
+#
+ifeq ($(CONFIG_SYS_THUMB_BUILD),y)
+ifeq ($(GAS_BUG_12532),)
+export GAS_BUG_12532:=$(shell if [ $(call binutils-version) -lt 0222 ] ; \
+ then echo y; else echo n; fi)
+endif
+ifeq ($(GAS_BUG_12532),y)
+PLATFORM_RELFLAGS += -fno-optimize-sibling-calls
+endif
+endif