From 842dfc11ea9a21f9825167c8a4f2834b205b0a79 Mon Sep 17 00:00:00 2001 From: Manuel Lauss Date: Fri, 7 Nov 2014 14:13:54 +0100 Subject: MIPS: Fix build with binutils 2.24.51+ Starting with version 2.24.51.20140728 MIPS binutils complain loudly about mixing soft-float and hard-float object files, leading to this build failure since GCC is invoked with "-msoft-float" on MIPS: {standard input}: Warning: .gnu_attribute 4,3 requires `softfloat' LD arch/mips/alchemy/common/built-in.o mipsel-softfloat-linux-gnu-ld: Warning: arch/mips/alchemy/common/built-in.o uses -msoft-float (set by arch/mips/alchemy/common/prom.o), arch/mips/alchemy/common/sleeper.o uses -mhard-float To fix this, we detect if GAS is new enough to support "-msoft-float" command option, and if it does, we can let GCC pass it to GAS; but then we also need to sprinkle the files which make use of floating point registers with the necessary ".set hardfloat" directives. Signed-off-by: Manuel Lauss Cc: Linux-MIPS Cc: Matthew Fortune Cc: Markos Chandras Cc: Maciej W. Rozycki Patchwork: https://patchwork.linux-mips.org/patch/8355/ Signed-off-by: Ralf Baechle --- arch/mips/Makefile | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'arch/mips/Makefile') diff --git a/arch/mips/Makefile b/arch/mips/Makefile index 23cb94806fbc..58076472bdd8 100644 --- a/arch/mips/Makefile +++ b/arch/mips/Makefile @@ -93,6 +93,15 @@ LDFLAGS_vmlinux += -G 0 -static -n -nostdlib KBUILD_AFLAGS_MODULE += -mlong-calls KBUILD_CFLAGS_MODULE += -mlong-calls +# +# pass -msoft-float to GAS if it supports it. However on newer binutils +# (specifically newer than 2.24.51.20140728) we then also need to explicitly +# set ".set hardfloat" in all files which manipulate floating point registers. +# +ifneq ($(call as-option,-Wa$(comma)-msoft-float,),) + cflags-y += -DGAS_HAS_SET_HARDFLOAT -Wa,-msoft-float +endif + cflags-y += -ffreestanding # -- cgit v1.2.3