Обсуждение: MinGW cross compilation failure on Debian trixie
Hi,
I am working on upgrading Debian bookworm CI images to Debian trixie.
CompilerWarnings CI task's mingw_cross_warning_script failed with [1]:
```
make -s -j${BUILD_JOBS} clean
time make -s -j${BUILD_JOBS} world-bin
In file included from ../../../../src/include/port.h:16,
from ../../../../src/include/c.h:1353,
from ../../../../src/include/postgres.h:48,
from pg_locale_libc.c:12:
pg_locale_libc.c: In function ‘wc_isdigit_libc_mb’:
../../../../src/include/port/win32_port.h:438:20: error: implicit
declaration of function ‘_iswctype_l’; did you mean ‘_isctype_l’?
[-Wimplicit-function-declaration]
438 | #define iswdigit_l _iswdigit_l
| ^~~~~~~~~~~
pg_locale_libc.c:178:16: note: in expansion of macro ‘iswdigit_l’
178 | return iswdigit_l((wint_t) wc, locale->info.lt);
| ^~~~~~~~~~
make[4]: *** [<builtin>: pg_locale_libc.o] Error 1
make[4]: *** Waiting for unfinished jobs....
make[3]: *** [../../../src/backend/common.mk:37: adt-recursive] Error 2
make[2]: *** [common.mk:37: utils-recursive] Error 2
make[1]: *** [Makefile:42: all-backend-recurse] Error 2
make: *** [GNUmakefile:21: world-bin-src-recurse] Error 2
```
I am not sure if this problem is about Postgres or Debian yet; but I
wanted to share it.
I can reproduce this problem on my Debian sid machine on upstream,
REL_18_STABLE and REL_17_STABLE branches. REL_16_STABLE compiles
successfully. My specs are:
- Linux nbyavuz 6.16.7+deb14-amd64 #1 SMP PREEMPT_DYNAMIC Debian
6.16.7-1 (2025-09-11) x86_64 GNU/Linux
- gcc version 15.2.0 (Debian 15.2.0-4)
- mingw-w64-tools 12.0.0-5
- gcc-mingw-w64-x86-64-win32 14.2.0-19+27+b1
- g++-mingw-w64-x86-64-win32 14.2.0-19+27+b1
[1] https://cirrus-ci.com/task/6240816059908096
--
Regards,
Nazir Bilal Yavuz
Microsoft
On Fri, Sep 19, 2025 at 8:13 PM Nazir Bilal Yavuz <byavuz81@gmail.com> wrote:: > pg_locale_libc.c: In function ‘wc_isdigit_libc_mb’: > ../../../../src/include/port/win32_port.h:438:20: error: implicit > declaration of function ‘_iswctype_l’; did you mean ‘_isctype_l’? > [-Wimplicit-function-declaration] > 438 | #define iswdigit_l _iswdigit_l > | ^~~~~~~~~~~ > pg_locale_libc.c:178:16: note: in expansion of macro ‘iswdigit_l’ > 178 | return iswdigit_l((wint_t) wc, locale->info.lt); > | ^~~~~~~~~~ It looks like version 12 of mingw-w64-x86-64-dev, currently shipping in Debian trixie and sid, must have broken something that worked in version 8 from bullseye. Several different headers apparently compete to provide that family of functions, with a common guard _WCTYPE_DEFINED: https://github.com/mingw-w64/mingw-w64/blob/v12.x/mingw-w64-headers/crt/ctype.h https://github.com/mingw-w64/mingw-w64/blob/v12.x/mingw-w64-headers/crt/wchar.h https://github.com/mingw-w64/mingw-w64/blob/v12.x/mingw-w64-headers/crt/wctype.h I suspect that if you define _CTYPE_DISABLE_MACROS (for example in CPPFLAGS) then it might work. Assuming <ctype.h> wins (I guess so, it's included at the top of port.h), then I suppose it must use this definition, hiding the function of the same name: #define _iswdigit_l(_c,_p) (_iswctype_l(_c,_DIGIT,_p)) But _iswctype_l is only declared if: #if __MSVCRT_VERSION__ >= 0x800 It looks like the default __MSVCRT_VERSION__ is 0x700 (/usr/x86_64-w64-mingw32/include/_mingw.h). Hmm, so does UCRT make the problem go away? We wanted to do that already -- see pgql-bugs #18940. Try installing gcc-mingw-w64-ucrt64 and g++-mingw-w64-ucrt64 on the CI image, and changing the compilers like this, perhaps? - CC="ccache x86_64-w64-mingw32-gcc" \ - CXX="ccache x86_64-w64-mingw32-g++" + CC="ccache x86_64-w64-mingw32ucrt-gcc" \ + CXX="ccache x86_64-w64-mingw32ucrt-g++"
Hi, On 2025-09-20 00:51:55 +1200, Thomas Munro wrote: > On Fri, Sep 19, 2025 at 8:13 PM Nazir Bilal Yavuz <byavuz81@gmail.com> wrote:: > > pg_locale_libc.c: In function ‘wc_isdigit_libc_mb’: > > ../../../../src/include/port/win32_port.h:438:20: error: implicit > > declaration of function ‘_iswctype_l’; did you mean ‘_isctype_l’? > > [-Wimplicit-function-declaration] > > 438 | #define iswdigit_l _iswdigit_l > > | ^~~~~~~~~~~ > > pg_locale_libc.c:178:16: note: in expansion of macro ‘iswdigit_l’ > > 178 | return iswdigit_l((wint_t) wc, locale->info.lt); > > | ^~~~~~~~~~ > > It looks like version 12 of mingw-w64-x86-64-dev, currently shipping > in Debian trixie and sid, must have broken something that worked in > version 8 from bullseye. Several different headers apparently compete > to provide that family of functions, with a common guard > _WCTYPE_DEFINED: > > https://github.com/mingw-w64/mingw-w64/blob/v12.x/mingw-w64-headers/crt/ctype.h > https://github.com/mingw-w64/mingw-w64/blob/v12.x/mingw-w64-headers/crt/wchar.h > https://github.com/mingw-w64/mingw-w64/blob/v12.x/mingw-w64-headers/crt/wctype.h > > I suspect that if you define _CTYPE_DISABLE_MACROS (for example in > CPPFLAGS) then it might work. Assuming <ctype.h> wins (I guess so, > it's included at the top of port.h), then I suppose it must use this > definition, hiding the function of the same name: > > #define _iswdigit_l(_c,_p) (_iswctype_l(_c,_DIGIT,_p)) > > But _iswctype_l is only declared if: > > #if __MSVCRT_VERSION__ >= 0x800 > > It looks like the default __MSVCRT_VERSION__ is 0x700 > (/usr/x86_64-w64-mingw32/include/_mingw.h). Hmm, so does UCRT > make the problem go away? Yes, I actually just got this far - if I add -D_UCRT the build succeeds. That's not the right actual solution, but confirms this much. > We wanted to do that already -- see pgql-bugs #18940. Try installing > gcc-mingw-w64-ucrt64 and g++-mingw-w64-ucrt64 on the CI image, and changing > the compilers like this, perhaps? > > - CC="ccache x86_64-w64-mingw32-gcc" \ > - CXX="ccache x86_64-w64-mingw32-g++" > + CC="ccache x86_64-w64-mingw32ucrt-gcc" \ > + CXX="ccache x86_64-w64-mingw32ucrt-g++" The "--host=x86_64-w64-mingw32" would need to be adjusted too. The only reason we also specify CC/CXX explicitly is to use ccache... Switching to the ucrt binaries does fix the build with meson on debian unstable, fwiw. Nice. Greetings, Andres Freund