From bbb56c27228d4ad64aca858c5af49d0f2f11c645 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 6 Dec 2016 15:27:43 +0000 Subject: [PATCH] arm64: Add detection code for broken .inst support in binutils Binutils version up to (and including) 2.25 have a pathological behaviour when it comes to mixing .inst directive and arithmetic involving labels. The assembler complains about non-constant expressions and compilation stops pretty quickly. In order to detect this and work around it, let's add a bit of detection code that will set the CONFIG_BROKEN_GAS_INST option should a broken gas be detected. Acked-by: Will Deacon Signed-off-by: Marc Zyngier Signed-off-by: Catalin Marinas --- arch/arm64/Makefile | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile index 3635b8662724..b9a4a934ca05 100644 --- a/arch/arm64/Makefile +++ b/arch/arm64/Makefile @@ -37,10 +37,16 @@ $(warning LSE atomics not supported by binutils) endif endif -KBUILD_CFLAGS += -mgeneral-regs-only $(lseinstr) +brokengasinst := $(call as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n,,-DCONFIG_BROKEN_GAS_INST=1) + +ifneq ($(brokengasinst),) +$(warning Detected assembler with broken .inst; disassembly will be unreliable) +endif + +KBUILD_CFLAGS += -mgeneral-regs-only $(lseinstr) $(brokengasinst) KBUILD_CFLAGS += -fno-asynchronous-unwind-tables KBUILD_CFLAGS += $(call cc-option, -mpc-relative-literal-loads) -KBUILD_AFLAGS += $(lseinstr) +KBUILD_AFLAGS += $(lseinstr) $(brokengasinst) ifeq ($(CONFIG_CPU_BIG_ENDIAN), y) KBUILD_CPPFLAGS += -mbig-endian -- 2.20.1