From 5e58509bfe497c5e85db58f8213b0a44ac79dd3f Mon Sep 17 00:00:00 2001 From: Waldemar Brodkorb Date: Sat, 31 Mar 2018 19:54:20 +0200 Subject: [PATCH] toolchain-wrapper: use -ffp-contract=off on MIPS Xburst for gcc >= 4.6 Since gcc 4.6, GCC deprecated -mfused-madd, -ffp-contract=off should be used for the Xburst workaround. Tested with the MIPS Sourcery 2011.03 toolchain (based on gcc 4.5), the toolchain wrapper uses -mno-fused-madd, as expected: $ BR2_DEBUG_WRAPPER=2 ./output/host/bin/mips-linux-gnu-gcc -o toto toto.c Toolchain wrapper executing: '/home/thomas/toolchains/mips-2011.03/bin/mips-linux-gnu-gcc' '--sysroot' '/home/thomas/projets/buildroot/output/host/mipsel-buildroot-linux-gnu/sysroot' '-mabi=32' '-msoft-float' '-mno-fused-madd' '-EL' '-march=mips32r2' '-o' 'toto' 'toto.c' And with the MIPS Sourcery 2012.09 toolchain (based on gcc 4.7), the toolchain wrapper uses -ffp-contract=off, as expected: $ BR2_DEBUG_WRAPPER=2 ./output/host/bin/mips-linux-gnu-gcc -o toto toto.c Toolchain wrapper executing: '/home/thomas/toolchains/mips-2012.09/bin/mips-linux-gnu-gcc' '--sysroot' '/home/thomas/projets/buildroot/output/host/mipsel-buildroot-linux-gnu/sysroot' '-mabi=32' '-msoft-float' '-ffp-contract=off' '-EL' '-march=mips32r2' '-o' 'toto' 'toto.c' Fixes the ci20_defconfig build: https://gitlab.com/buildroot.org/buildroot/-/jobs/60303132 Signed-off-by: Waldemar Brodkorb [Thomas: rework to continue supporting pre-gcc-4.6 toolchains, extend the commit log after doing more testing.] Signed-off-by: Thomas Petazzoni Reviewed-by: Ezequiel Garcia Signed-off-by: Thomas Petazzoni --- toolchain/toolchain-wrapper.c | 3 +++ toolchain/toolchain-wrapper.mk | 6 ++++++ 2 files changed, 9 insertions(+) diff --git a/toolchain/toolchain-wrapper.c b/toolchain/toolchain-wrapper.c index 2928ea42d0..c5eb813dd0 100644 --- a/toolchain/toolchain-wrapper.c +++ b/toolchain/toolchain-wrapper.c @@ -82,6 +82,9 @@ static char *predef_args[] = { #ifdef BR_NO_FUSED_MADD "-mno-fused-madd", #endif +#ifdef BR_FP_CONTRACT_OFF + "-ffp-contract=off", +#endif #ifdef BR_BINFMT_FLAT "-Wl,-elf2flt", #endif diff --git a/toolchain/toolchain-wrapper.mk b/toolchain/toolchain-wrapper.mk index 0b26037d48..b8074efc3c 100644 --- a/toolchain/toolchain-wrapper.mk +++ b/toolchain/toolchain-wrapper.mk @@ -32,8 +32,14 @@ endif # Avoid FPU bug on XBurst CPUs ifeq ($(BR2_mips_xburst),y) +# Before gcc 4.6, -mno-fused-madd was needed, after -ffp-contract is +# needed +ifeq ($(BR2_TOOLCHAIN_GCC_AT_LEAST_4_6),y) +TOOLCHAIN_WRAPPER_ARGS += -DBR_FP_CONTRACT_OFF +else TOOLCHAIN_WRAPPER_ARGS += -DBR_NO_FUSED_MADD endif +endif ifeq ($(BR2_CCACHE_USE_BASEDIR),y) TOOLCHAIN_WRAPPER_ARGS += -DBR_CCACHE_BASEDIR='"$(BASE_DIR)"' -- 2.39.2