Package: g++-12
Version: 12.2.0-14
Severity: important
X-Debbugs-Cc: userreen10...@gmail.com, mikegreen10...@gmail.com
-- System Information:
Debian Release: 12.6
APT prefers stable-updates
APT policy: (500, 'stable-updates'), (500, 'stable-security'), (500, 'stable')
Architecture: arm64 (aarch64)
Foreign Architectures: armhf
Kernel: Linux 6.6.31+rpt-rpi-v8 (SMP w/4 CPU threads; PREEMPT)
Kernel taint flags: TAINT_CRAP
Locale: LANG=en_US, LC_CTYPE=en_US (charmap=ISO-8859-1) (ignored: LC_ALL set to
en_US), LANGUAGE=en_US
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
Versions of packages g++-12 depends on:
ii gcc-12 12.2.0-14
ii gcc-12-base 12.2.0-14
ii libc6 2.36-9+rpt2+deb12u7
ii libgmp10 2:6.2.1+dfsg1-1.1
ii libisl23 0.25-1.1
ii libmpc3 1.3.1-1
ii libmpfr6 4.2.0-1
ii libstdc++-12-dev 12.2.0-14
ii libzstd1 1.5.4+dfsg2-5
ii zlib1g 1:1.2.13.dfsg-1
g++-12 recommends no packages.
Versions of packages g++-12 suggests:
pn gcc-12-doc <none>
-- no debconf information
I am looking to use 16-bit floarting point on my Pi5. I find that gcc supports
_Float16 (which is I think the standard to access 16b FP). This works great
for C but not for C++:
user@raspberrypi:~ $ cat x.c
_Float16 test(){
return 1.0;
}
user@raspberrypi:~ $ gcc -S -3 x.c
gcc: error: unrecognized command-line option '-3'
user@raspberrypi:~ $ gcc -S -O3 x.c
user@raspberrypi:~ $ cat x.s
.arch armv8-a
.file "x.c"
.text
.align 2
.p2align 4,,11
.global test
.type test, %function
test:
.LFB0:
.cfi_startproc
movi v0.4h, 0x3c, lsl 8
ret
.cfi_endproc
.LFE0:
.size test, .-test
.ident "GCC: (Debian 12.2.0-14) 12.2.0"
.section .note.GNU-stack,"",@progbits
user@raspberrypi:~ $ cp x.c x.cc
user@raspberrypi:~ $ g++ -O3 -S x.cc
x.cc:2:1: error: '_Float16' does not name a type
2 | _Float16 test(){
| ^~~~~~~~
user@raspberrypi:~ $ uname -a
Linux raspberrypi 6.6.31+rpt-rpi-v8 #1 SMP PREEMPT Debian 1:6.6.31-1+rpt1
(2024-05-29) aarch64 GNU/Linux
user@raspberrypi:~ $ gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/aarch64-linux-gnu/12/lto-wrapper
Target: aarch64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Debian 12.2.0-14'
--with-bugurl=file:///usr/share/doc/gcc-12/README.Bugs
--enable-languages=c,ada,c++,go,d,fortran,objc,obj-c++,m2 --prefix=/usr
--with-gcc-major-version-only --program-suffix=-12
--program-prefix=aarch64-linux-gnu- --enable-shared --enable-linker-build-id
--libexecdir=/usr/lib --without-included-gettext --enable-threads=posix
--libdir=/usr/lib --enable-nls --enable-clocale=gnu --enable-libstdcxx-debug
--enable-libstdcxx-time=yes --with-default-libstdcxx-abi=new
--enable-gnu-unique-object --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 --enable-fix-cortex-a53-843419
--disable-werror --enable-checking=release --build=aarch64-linux-gnu
--host=aarch64-linux-gnu --target=aarch64-linux-gnu
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 12.2.0 (Debian 12.2.0-14)
user@raspberrypi:~ $ g++ -v
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/usr/lib/gcc/aarch64-linux-gnu/12/lto-wrapper
Target: aarch64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Debian 12.2.0-14'
--with-bugurl=file:///usr/share/doc/gcc-12/README.Bugs
--enable-languages=c,ada,c++,go,d,fortran,objc,obj-c++,m2 --prefix=/usr
--with-gcc-major-version-only --program-suffix=-12
--program-prefix=aarch64-linux-gnu- --enable-shared --enable-linker-build-id
--libexecdir=/usr/lib --without-included-gettext --enable-threads=posix
--libdir=/usr/lib --enable-nls --enable-clocale=gnu --enable-libstdcxx-debug
--enable-libstdcxx-time=yes --with-default-libstdcxx-abi=new
--enable-gnu-unique-object --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 --enable-fix-cortex-a53-843419
--disable-werror --enable-checking=release --build=aarch64-linux-gnu
--host=aarch64-linux-gnu --target=aarch64-linux-gnu
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 12.2.0 (Debian 12.2.0-14)
