(Sorry, never a bringer of good news...)
> From: Jonathan Wakely <jwak...@redhat.com>
> Date: Mon, 8 Jan 2024 01:15:50 +0000
> Tested x86_64-linux and aarch64-linux. Pushed to trunk.
>
> -- >8 --
>
> This change ensures that char and wchar_t arguments are formatted
> consistently when using integer presentation types. This avoids
> non-portable std::format output that depends on whether char and wchar_t
> happen to be signed or unsigned on the target. Formatting '\xff' as an
> integer will now always format 255 and not sometimes -1. This was
> approved in Kona 2023 as a DR for C++20 so the change is implemented
> unconditionally.
>
> Also make character formatters check for _Pres_c explicitly and call
> _M_format_character directly. This avoid the overhead of calling format
> and _S_to_character and then calling _M_format_character anyway.
>
> libstdc++-v3/ChangeLog:
>
> * include/bits/version.def (format_uchar): Define.
> * include/bits/version.h: Regenerate.
> * include/std/format (formatter<C, C>::format): Check for
> _Pres_c and call _M_format_character directly. Cast C to its
> unsigned equivalent for formatting as an integer.
> (formatter<char, wchar_t>::format): Likewise.
> (basic_format_arg(T&)): Store char arguments as unsigned char
> for formatting to a wide string.
> * testsuite/std/format/functions/format.cc: Adjust test. Check
> formatting of
For some reason, this (r14-6990-g74a0dab18292be) breaks a
build of (newlib targets) at least cris-elf and arm-eabi:
libtool: compile: /obj/./gcc/xgcc -shared-libgcc -B/obj/./gcc -nostdinc++
-L/obj/cris-elf/libstdc++-v3/src -L/obj/cris-elf/libstdc++-v3/src/.libs
-L/obj/cris-elf/libstdc++-v3/libsupc++/.libs -nostdinc -B/obj/cris-elf/newlib/
-isystem /obj/cris-elf/newlib/targ-include -isystem /x/gcc/newlib/libc/include
-B/obj/cris-elf/libgloss/cris -L/obj/cris-elf/libgloss/libnosys
-L/x/gcc/libgloss/cris -B/x/cris-elf/pre/cris-elf/bin/
-B/x/cris-elf/pre/cris-elf/lib/ -isystem /x/cris-elf/pre/cris-elf/include
-isystem /x/cris-elf/pre/cris-elf/sys-include -I/x/gcc/libstdc++-v3/../libgcc
-I/obj/cris-elf/libstdc++-v3/include/cris-elf
-I/obj/cris-elf/libstdc++-v3/include -I/x/gcc/libstdc++-v3/libsupc++
-std=gnu++20 -fno-implicit-templates -Wall -Wextra -Wwrite-strings -Wcast-qual
-Wabi=2 -fdiagnostics-show-location=once -ffunction-sections -fdata-sections
-frandom-seed=tzdb.lo -fimplicit-templates -g -O2 -I. -c
/x/gcc/libstdc++-v3/src/c++20/tzdb.cc -o tzdb.o
In file included from /x/gcc/newlib/libc/include/time.h:11,
from /obj/cris-elf/libstdc++-v3/include/ctime:42,
from /obj/cris-elf/libstdc++-v3/include/bits/chrono.h:40,
from /obj/cris-elf/libstdc++-v3/include/chrono:41,
from /x/gcc/libstdc++-v3/src/c++20/tzdb.cc:31:
/obj/cris-elf/libstdc++-v3/include/bits/unicode.h:86:37: error: declaration
does not declare anything [-fpermissive]
86 | inline constexpr _Null_sentinel_t __null_sentinel;
| ^~~~~~~~~~~~~~~
make[5]: *** [Makefile:754: tzdb.lo] Error 1
I don't see anything immediately related to that line in the
patch, though, so the actual cause and fix isn't obvious, at
least to me.
brgds, H-P
