Hi,
I am seeing a failure to build in crosstool-NG configurations where GCC8
is configured with --with-cpu=... option:
[ALL ] libtool: compile:
/home/avn/work/ctng/crosstool-ng/.build/arm-cortex_a15-linux-gnueabihf/build/build-cc-gcc-final/./gcc/xgcc
-B/home/avn/work/ctng/crosstool-ng/.build/arm-cortex_a15-linux-gnueabihf/build/build-cc-gcc-final/./gcc/
-B/home/avn/x-tools/arm-cortex_a15-linux-gnueabihf/arm-cortex_a15-linux-gnueabihf/bin/
-B/home/avn/x-tools/arm-cortex_a15-linux-gnueabihf/arm-cortex_a15-linux-gnueabihf/lib/
-isystem
/home/avn/x-tools/arm-cortex_a15-linux-gnueabihf/arm-cortex_a15-linux-gnueabihf/include
-isystem
/home/avn/x-tools/arm-cortex_a15-linux-gnueabihf/arm-cortex_a15-linux-gnueabihf/sys-include
-DHAVE_CONFIG_H
-I/home/avn/work/ctng/crosstool-ng/.build/arm-cortex_a15-linux-gnueabihf/src/gcc/libatomic/config/arm
-I/home/avn/work/ctng/crosstool-ng/.build/arm-cortex_a15-linux-gnueabihf/src/gcc/libatomic/config/linux/arm
-I/home/avn/work/ctng/crosstool-ng/.build/arm-cortex_a15-linux-gnueabihf/src/gcc/libatomic/config/posix
-I/home/avn/work/ctng/crosstool-ng/.build/arm-cortex_a15-linux-gnueabihf/src/gcc/libatomic
-I. -Wall -Werror -pthread -mlittle-endian -mcpu=cortex-a15
-mfpu=neon-vfpv4 -mhard-float -g -Os -MT load_1_1_.lo -MD -MP -MF
.deps/load_1_1_.lo.Ppo -DN=1 -DIFUNC_ALT=1 -march=armv7-a+fp -c
/home/avn/work/ctng/crosstool-ng/.build/arm-cortex_a15-linux-gnueabihf/src/gcc/libatomic/config/linux/arm/load_n.c
-fPIC -DPIC -o .libs/load_1_1_.o
[ERROR] cc1: error: switch -mcpu=cortex-a15 conflicts with
-march=armv7-a switch [-Werror]
GCC is configured with:
CC_FOR_BUILD='x86_64-build_pc-linux-gnu-gcc' CFLAGS='-O2 -g -pipe
-I/home/avn/work/ctng/crosstool-ng/.build/arm-cortex_a15-linux-gnueabihf/buildtools/include
' CFLAGS_FOR_BUILD='-O2 -g -pipe
-I/home/avn/work/ctng/crosstool-ng/.build/arm-cortex_a15-linux-gnueabihf/buildtools/include
' CXXFLAGS='-O2 -g -pipe
-I/home/avn/work/ctng/crosstool-ng/.build/arm-cortex_a15-linux-gnueabihf/buildtools/include
' CXXFLAGS_FOR_BUILD='-O2 -g -pipe
-I/home/avn/work/ctng/crosstool-ng/.build/arm-cortex_a15-linux-gnueabihf/buildtools/include
'
LDFLAGS='-L/home/avn/work/ctng/crosstool-ng/.build/arm-cortex_a15-linux-gnueabihf/buildtools/lib
-lstdc++ -lm' CFLAGS_FOR_TARGET=' -mlittle-endian -mcpu=cortex-a15
-mfpu=neon-vfpv4 -mhard-float ' CXXFLAGS_FOR_TARGET='
-mlittle-endian -mcpu=cortex-a15 -mfpu=neon-vfpv4 -mhard-float '
LDFLAGS_FOR_TARGET=' -Wl,-EL ' '/bin/bash'
'/home/avn/work/ctng/crosstool-ng/.build/arm-cortex_a15-linux-gnueabihf/src/gcc/configure'
'--build=x86_64-build_pc-linux-gnu' '--host=x86_64-build_pc-linux-gnu'
'--target=arm-cortex_a15-linux-gnueabihf'
'--prefix=/home/avn/x-tools/arm-cortex_a15-linux-gnueabihf'
'--with-sysroot=/home/avn/x-tools/arm-cortex_a15-linux-gnueabihf/arm-cortex_a15-linux-gnueabihf/sysroot'
'--enable-languages=c,c++' '--with-cpu=cortex-a15'
'--with-fpu=neon-vfpv4' '--with-float=hard'
'--with-pkgversion=crosstool-NG 1.23.0-392-gd274ab06-dirty'
'--enable-__cxa_atexit' '--disable-libmudflap' '--disable-libgomp'
'--disable-libssp' '--disable-libquadmath'
'--disable-libquadmath-support' '--disable-libsanitizer'
'--disable-libmpx'
'--with-gmp=/home/avn/work/ctng/crosstool-ng/.build/arm-cortex_a15-linux-gnueabihf/buildtools'
'--with-mpfr=/home/avn/work/ctng/crosstool-ng/.build/arm-cortex_a15-linux-gnueabihf/buildtools'
'--with-mpc=/home/avn/work/ctng/crosstool-ng/.build/arm-cortex_a15-linux-gnueabihf/buildtools'
'--with-isl=/home/avn/work/ctng/crosstool-ng/.build/arm-cortex_a15-linux-gnueabihf/buildtools'
'--enable-lto' '--with-host-libstdcxx=-static-libgcc
-Wl,-Bstatic,-lstdc++,-Bdynamic -lm' '--enable-threads=posix'
'--enable-target-optspace' '--enable-plugin' '--enable-gold'
'--disable-nls' '--disable-multilib'
'--with-local-prefix=/home/avn/x-tools/arm-cortex_a15-linux-gnueabihf/arm-cortex_a15-linux-gnueabihf/sysroot'
'--enable-long-long'
The problem, as far as I understand, is that libatomic unconditionally
adds -march=armv7-a for arm-*-linux configurations; here is a fragment
of its Makefile.am:
## On a target-specific basis, include alternates to be selected by IFUNC.
if HAVE_IFUNC
...
if ARCH_ARM_LINUX
IFUNC_OPTIONS = -march=armv7-a+fp -DHAVE_KERNEL64
libatomic_la_LIBADD += $(foreach s,$(SIZES),$(addsuffix
_$(s)_1_.lo,$(SIZEOBJS)))
libatomic_la_LIBADD += $(addsuffix _8_2_.lo,$(SIZEOBJS))
endif
The -mcpu=cortex-a15 comes from the CPU selected during configure.
Is --with-cpu still allowed for ARM/Linux targets with GCC8? If it is,
what should be the fix for this - only add -march=... if CPU is not
selected?
Regards,
Alexey.
