On Thu, Jun 30, 2022 at 08:28:42AM +0200, Mathieu Malaterre wrote: > If I compare gcc-10 vs gcc-11 I see: > > malat@abel ~ % gcc-10 --verbose > Using built-in specs. > COLLECT_GCC=gcc-10 > COLLECT_LTO_WRAPPER=/usr/lib/gcc/arm-linux-gnueabihf/10/lto-wrapper > Target: arm-linux-gnueabihf > Configured with: ../src/configure -v --with-pkgversion='Debian > 10.3.0-16' --with-bugurl=file:///usr/share/doc/gcc-10/README.Bugs > --enable-languages=c,ada,c++,go,d,fortran,objc,obj-c++,m2 > --prefix=/usr --with-gcc-major-version-only --program-suffix=-10 > --program-prefix=arm-linux-gnueabihf- --enable-shared > --enable-linker-build-id --libexecdir=/usr/lib > --without-included-gettext --enable-threads=posix --libdir=/usr/lib > --enable-nls --enable-bootstrap --enable-clocale=gnu > --enable-libstdcxx-debug --enable-libstdcxx-time=yes > --with-default-libstdcxx-abi=new --enable-gnu-unique-object > --disable-libitm --disable-libquadmath --disable-libquadmath-support > --enable-plugin --enable-default-pie --with-system-zlib > --enable-libphobos-checking=release --with-target-system-zlib=auto > --enable-objc-gc=auto --enable-multiarch --disable-sjlj-exceptions > --with-arch=armv7-a --with-fpu=vfpv3-d16 --with-float=hard > --with-mode=thumb --disable-werror --enable-checking=release > --build=arm-linux-gnueabihf --host=arm-linux-gnueabihf > --target=arm-linux-gnueabihf > Thread model: posix > Supported LTO compression algorithms: zlib zstd > gcc version 10.3.0 (Debian 10.3.0-16) > > while > > malat@abel ~ % gcc-11 --verbose > Using built-in specs. > COLLECT_GCC=gcc-11 > COLLECT_LTO_WRAPPER=/usr/lib/gcc/arm-linux-gnueabihf/11/lto-wrapper > Target: arm-linux-gnueabihf > Configured with: ../src/configure -v --with-pkgversion='Debian > 11.3.0-3' --with-bugurl=file:///usr/share/doc/gcc-11/README.Bugs > --enable-languages=c,ada,c++,go,d,fortran,objc,obj-c++,m2 > --prefix=/usr --with-gcc-major-version-only --program-suffix=-11 > --program-prefix=arm-linux-gnueabihf- --enable-shared > --enable-linker-build-id --libexecdir=/usr/lib > --without-included-gettext --enable-threads=posix --libdir=/usr/lib > --enable-nls --enable-bootstrap --enable-clocale=gnu > --enable-libstdcxx-debug --enable-libstdcxx-time=yes > --with-default-libstdcxx-abi=new --enable-gnu-unique-object > --disable-libitm --disable-libquadmath --disable-libquadmath-support > --enable-plugin --enable-default-pie --with-system-zlib > --enable-libphobos-checking=release --with-target-system-zlib=auto > --enable-objc-gc=auto --enable-multiarch --disable-sjlj-exceptions > --with-arch=armv7-a+fp --with-float=hard --with-mode=thumb > --disable-werror --enable-checking=release --build=arm-linux-gnueabihf > --host=arm-linux-gnueabihf --target=arm-linux-gnueabihf > Thread model: posix > Supported LTO compression algorithms: zlib zstd > gcc version 11.3.0 (Debian 11.3.0-3) > > Could someone confirm, the spec file is accurate for Debian armhf (no > neon) ? I fail to understand why spec file would be different for us > (--with-arch=armv7-a --with-fpu=vfpv3-d16 suddenly became > --with-arch=armv7-a+fp). > > If I read the doc online correctly: > > https://gcc.gnu.org/onlinedocs/gcc/ARM-Options.html > > states: > > -mfpu=name > [...] > The setting ‘auto’ is the default and is special. It causes the > compiler to select the floating-point and Advanced SIMD instructions > based on the settings of -mcpu and -march. > > In the case of valgrind I can see: > > ` -marm -mcpu=cortex-a8` > > I cannot find in the doc what 'cortex-a8' stands for: neon or not neon ?
Cortex-A8 always has neon as far as I remember. Cortex-A9 unfortunately has it optional and of course some non Cortex arm implementations don't have neon either. So cortex-a8 is not a valid choice as a generic arm v7 armhf processor. -- Len Sorensen
