msp430-elf cross-compiler: libstdc++ supported?

msp430-elf cross-compiler: libstdc++ supported?

[Florian Weimer]

I'm trying to validate a change to gcc/config/msp430/msp430.cc.
The cross-compiler builds as far as I can tell, but I hit a snag while
configuring libstdc++:

checking for shl_load... configure: error: Link tests are not allowed after GCC_NO_EXECUTABLES.
make[1]: *** [Makefile:12334: configure-target-libstdc++-v3] Error 1
make[1]: Leaving directory '/root/msp/build-gcc'

Is this expected?  Is libstdc++ even supported for this target?
Thanks,
Florian

Re: msp430-elf cross-compiler: libstdc++ supported?

[Jonathan Wakely]

On Tue, 8 Nov 2022 at 11:22, Florian Weimer via Libstdc++
<libstdc++@gcc.gnu.org> wrote:
>
> I'm trying to validate a change to gcc/config/msp430/msp430.cc.
> The cross-compiler builds as far as I can tell, but I hit a snag while
> configuring libstdc++:
>
> checking for shl_load... configure: error: Link tests are not allowed after GCC_NO_EXECUTABLES.
> make[1]: *** [Makefile:12334: configure-target-libstdc++-v3] Error 1
> make[1]: Leaving directory '/root/msp/build-gcc'
>
> Is this expected?  Is libstdc++ even supported for this target?

Yes. What's your configure command? You probably need at least --with-newlib.

I think my last successful msp430 build was using:

.../gcc/configure --target=msp430-elf --prefix=$HOME/gcc/msp430-elf
--disable-libcc1 --disable-libgomp --disable-libitm --disable-libssp
--disable-libvtv --disable-nls --with-system-zlib
target_alias=msp430-elf --disable-libstdcxx-pch
--disable-full-memory-range --with-newlib --enable-libstdcxx
--enable-languages=c,c++

With the cross binutils already installed to $PREFIX/gcc/msp430-elf

Re: msp430-elf cross-compiler: libstdc++ supported?

[Jonathan Wakely]

On Tue, 8 Nov 2022 at 12:37, Jonathan Wakely wrote:
>
> On Tue, 8 Nov 2022 at 11:22, Florian Weimer via Libstdc++
> <libstdc++@gcc.gnu.org> wrote:
> >
> > I'm trying to validate a change to gcc/config/msp430/msp430.cc.
> > The cross-compiler builds as far as I can tell, but I hit a snag while
> > configuring libstdc++:
> >
> > checking for shl_load... configure: error: Link tests are not allowed after GCC_NO_EXECUTABLES.
> > make[1]: *** [Makefile:12334: configure-target-libstdc++-v3] Error 1
> > make[1]: Leaving directory '/root/msp/build-gcc'
> >
> > Is this expected?  Is libstdc++ even supported for this target?
>
> Yes. What's your configure command? You probably need at least --with-newlib.
>
> I think my last successful msp430 build was using:
>
> .../gcc/configure --target=msp430-elf --prefix=$HOME/gcc/msp430-elf
> --disable-libcc1 --disable-libgomp --disable-libitm --disable-libssp
> --disable-libvtv --disable-nls --with-system-zlib
> target_alias=msp430-elf --disable-libstdcxx-pch
> --disable-full-memory-range --with-newlib --enable-libstdcxx
> --enable-languages=c,c++
>
> With the cross binutils already installed to $PREFIX/gcc/msp430-elf

Oh actually the libstdc++ build fails on trunk, but that is a very
recent regression and happens after configure succeeds:

/home/jwakely/src/gcc/gcc/libstdc++-v3/src/c++17/floating_from_chars.cc:
In function 'std::from_chars_result
std::{anonymous}::__floating_from_chars_hex(const char*, const char*,
T&)':
/home/jwakely/src/gcc/gcc/libstdc++-v3/src/c++17/floating_from_chars.cc:786:9:
error: 'fast_float' has not been declared
 786 |       = fast_float::binary_format<T>::mantissa_explicit_bits();
     |         ^~~~~~~~~~
/home/jwakely/src/gcc/gcc/libstdc++-v3/src/c++17/floating_from_chars.cc:786:36:
error: expected primary-expression before '>' token
 786 |       = fast_float::binary_format<T>::mantissa_explicit_bits();
     |                                    ^
libtool: compile:  /home/jwakely/src/gcc/build-16bit/./gcc/xgcc
-shared-libgcc -B/home/jwakely/src/gcc/build-16bit/./gcc -nostdinc++
-L/home/jwakely/src/gcc/build-16bit/msp430-elf/libstdc++-v3/src
-L/home/jwakely/src/gcc/build-16bit/msp430-elf/libstdc++-v3/src/.libs
-L/home/jwakely/src/gcc/build-16bit/msp430-elf/li
bstdc++-v3/libsupc++/.libs -nostdinc
-B/home/jwakely/src/gcc/build-16bit/msp430-elf/newlib/ -isystem
/home/jwakely/src/gcc/build-16bit/msp430-elf/newlib/targ-include
-isystem /home/jwakely/src/gcc/gcc/newlib/libc/include
-B/home/jwakely/src/gcc/build-16bit/msp430-elf/libgloss/msp430
-L/home/jwakely/src/gcc/build-16
bit/msp430-elf/libgloss/libnosys
-L/home/jwakely/src/gcc/gcc/libgloss/msp430
-B/home/jwakely/gcc/msp430-elf/msp430-elf/bin/
-B/home/jwakely/gcc/msp430-elf/msp430-elf/lib/ -isystem
/home/jwakely/gcc/msp430-elf/msp430-elf/include -isystem
/home/jwakely/gcc/msp430-elf/msp430-elf/sys-include
-I/home/jwakely/src/gcc/gcc
/libstdc++-v3/../libgcc
-I/home/jwakely/src/gcc/build-16bit/msp430-elf/libstdc++-v3/include/msp430-elf
-I/home/jwakely/src/gcc/build-16bit/msp430-elf/libstdc++-v3/include
-I/home/jwakely/src/gcc/gcc/libstdc++-v3/libsupc++ -std=gnu++17
-nostdinc++ -fno-implicit-templates -Wall -Wextra -Wwrite-strings
-Wcast-qual -Wa
bi=2 -fdiagnostics-show-location=once -ffunction-sections
-fdata-sections -frandom-seed=string-inst.lo -fimplicit-templates -g
-O2 -c /home/jwakely/src/gcc/gcc/libstdc++-v3/src/c++17/string-inst.cc
-o string-inst.o
/bin/sh ../../libtool --tag CXX --tag disable-shared   --mode=compile
/home/jwakely/src/gcc/build-16bit/./gcc/xgcc -shared-libgcc
-B/home/jwakely/src/gcc/build-16bit/./gcc -nostdinc++
-L/home/jwakely/src/gcc/build-16bit/msp430-elf/libstdc++-v3/src
-L/home/jwakely/src/gcc/build-16bit/msp430-elf/libstdc++-v3/src/.lib
s -L/home/jwakely/src/gcc/build-16bit/msp430-elf/libstdc++-v3/libsupc++/.libs
-nostdinc -B/home/jwakely/src/gcc/build-16bit/msp430-elf/newlib/
-isystem /home/jwakely/src/gcc/build-16bit/msp430-elf/newlib/targ-include
-isystem /home/jwakely/src/gcc/gcc/newlib/libc/include
-B/home/jwakely/src/gcc/build-16bit/msp430-e
lf/libgloss/msp430
-L/home/jwakely/src/gcc/build-16bit/msp430-elf/libgloss/libnosys
-L/home/jwakely/src/gcc/gcc/libgloss/msp430
-B/home/jwakely/gcc/msp430-elf/msp430-elf/bin/
-B/home/jwakely/gcc/msp430-elf/msp430-elf/lib/ -isystem
/home/jwakely/gcc/msp430-elf/msp430-elf/include -isystem
/home/jwakely/gcc/msp430-elf
/msp430-elf/sys-include
-I/home/jwakely/src/gcc/gcc/libstdc++-v3/../libgcc
-I/home/jwakely/src/gcc/build-16bit/msp430-elf/libstdc++-v3/include/msp430-elf
-I/home/jwakely/src/gcc/build-16bit/msp430-elf/libstdc++-v3/include
-I/home/jwakely/src/gcc/gcc/libstdc++-v3/libsupc++   -std=gnu++17
-nostdinc++   -fno-implic
it-templates  -Wall -Wextra -Wwrite-strings -Wcast-qual -Wabi=2
-fdiagnostics-show-location=once   -ffunction-sections -fdata-sections
 -frandom-seed=cow-string-inst.lo  -fimplicit-templates -g -O2  -c -o
cow-string-inst.lo
/home/jwakely/src/gcc/gcc/libstdc++-v3/src/c++17/cow-string-inst.cc
/home/jwakely/src/gcc/gcc/libstdc++-v3/src/c++17/floating_from_chars.cc:786:39:
error: '::mantissa_explicit_bits' has not been declared
 786 |       = fast_float::binary_format<T>::mantissa_explicit_bits();
     |                                       ^~~~~~~~~~~~~~~~~~~~~~
/home/jwakely/src/gcc/gcc/libstdc++-v3/src/c++17/floating_from_chars.cc:789:24:
error: 'fast_float' was not declared in this scope
 789 |         : is_same_v<T, fast_float::floating_type_float16_t> ? 5 : 8;
     |                        ^~~~~~~~~~
/home/jwakely/src/gcc/gcc/libstdc++-v3/src/c++17/floating_from_chars.cc:789:11:
error: parse error in template argument list
 789 |         : is_same_v<T, fast_float::floating_type_float16_t> ? 5 : 8;
     |           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/jwakely/src/gcc/gcc/libstdc++-v3/src/c++17/floating_from_chars.cc:947:30:
error: parse error in template argument list
 947 |                           || is_same_v<T,
     |                              ^~~~~~~~~~~~
 948 |
fast_float::floating_type_bfloat16_t>)
     |
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/jwakely/src/gcc/gcc/libstdc++-v3/src/c++17/floating_from_chars.cc:1132:24:
error: parse error in template argument list
1132 |     else if constexpr (is_same_v<T,
fast_float::floating_type_bfloat16_t>)
     |                        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~