celt/speex fails to build with _FORTIFY_SOURCE=2

[lazka]

to clarify: celt builds fine for all envs without any modification. Forcing _FORTIFY_SOURCE results in this error:

Using:

diff --git a/mingw-w64-celt/PKGBUILD b/mingw-w64-celt/PKGBUILD
index a1e1c7d8e..6970acc67 100644
--- a/mingw-w64-celt/PKGBUILD
+++ b/mingw-w64-celt/PKGBUILD
@@ -24,6 +24,8 @@ prepare() {
 build() {
   export lt_cv_deplibs_check_method='pass_all'

+  export CFLAGS+=" -D_FORTIFY_SOURCE=2"
+
   [[ -d "${srcdir}/build-${MINGW_CHOST}" ]] && rm -rf "${srcdir}/build-${MINGW_CHOST}"
   mkdir -p "${srcdir}/build-${MINGW_CHOST}"
   cd "${srcdir}/build-${MINGW_CHOST}"

$ MINGW_ARCH=mingw64 makepkg-mingw -Csfr --noconfirm --nocheck
...
In file included from ../../celt-0.11.3/tools/celtdec.c:53:
C:/msys64/mingw64/include/io.h: In function '_open':
C:/msys64/mingw64/include/io.h:407:7: error: invalid use of '__builtin_va_arg_pack_len ()'
  407 |   if (__builtin_va_arg_pack_len() > 1)
      |       ^~~~~~~~~~~~~~~~~~~~~~~~~~~
C:/msys64/mingw64/include/io.h:408:12: error: invalid use of '__builtin_va_arg_pack ()'
  408 |     return __mingw_call__open_warn_toomany(__filename, __flags, __builtin_va_arg_pack());
      |            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
C:/msys64/mingw64/include/io.h:413:10: error: invalid use of '__builtin_va_arg_pack ()'
  413 |   return __mingw_call__open(__filename, __flags, __builtin_va_arg_pack());
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
C:/msys64/mingw64/include/io.h: In function '_sopen':
C:/msys64/mingw64/include/io.h:425:7: error: invalid use of '__builtin_va_arg_pack_len ()'
  425 |   if (__builtin_va_arg_pack_len() > 1)
      |       ^~~~~~~~~~~~~~~~~~~~~~~~~~~
C:/msys64/mingw64/include/io.h:426:12: error: invalid use of '__builtin_va_arg_pack ()'
  426 |     return __mingw_call__sopen_warn_toomany(__filename, __flags, __share, __builtin_va_arg_pack());
      |            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
C:/msys64/mingw64/include/io.h:431:10: error: invalid use of '__builtin_va_arg_pack ()'
  431 |   return __mingw_call__sopen(__filename, __flags, __share, __builtin_va_arg_pack());
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
C:/msys64/mingw64/include/io.h: In function '_wopen':
C:/msys64/mingw64/include/io.h:443:7: error: invalid use of '__builtin_va_arg_pack_len ()'
  443 |   if (__builtin_va_arg_pack_len() > 1)
      |       ^~~~~~~~~~~~~~~~~~~~~~~~~~~
C:/msys64/mingw64/include/io.h:444:12: error: invalid use of '__builtin_va_arg_pack ()'
  444 |     return __mingw_call__wopen_warn_toomany(__filename, __flags, __builtin_va_arg_pack());
      |            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
C:/msys64/mingw64/include/io.h:449:10: error: invalid use of '__builtin_va_arg_pack ()'
  449 |   return __mingw_call__wopen(__filename, __flags, __builtin_va_arg_pack());
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
C:/msys64/mingw64/include/io.h: In function '_wsopen':
C:/msys64/mingw64/include/io.h:461:7: error: invalid use of '__builtin_va_arg_pack_len ()'
  461 |   if (__builtin_va_arg_pack_len() > 1)
      |       ^~~~~~~~~~~~~~~~~~~~~~~~~~~
C:/msys64/mingw64/include/io.h:462:12: error: invalid use of '__builtin_va_arg_pack ()'
  462 |     return __mingw_call__wsopen_warn_toomany(__filename, __flags, __share, __builtin_va_arg_pack());
      |            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
C:/msys64/mingw64/include/io.h:467:10: error: invalid use of '__builtin_va_arg_pack ()'
  467 |   return __mingw_call__wsopen(__filename, __flags, __share, __builtin_va_arg_pack());
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In function '_open',
    inlined from 'open' at C:/msys64/mingw64/include/io.h:474:10:
C:/msys64/mingw64/include/io.h:407:7: error: invalid use of '__builtin_va_arg_pack_len ()'
  407 |   if (__builtin_va_arg_pack_len() > 1)
      |       ^~~~~~~~~~~~~~~~~~~~~~~~~~~
C:/msys64/mingw64/include/io.h:408:12: error: invalid use of '__builtin_va_arg_pack ()'
  408 |     return __mingw_call__open_warn_toomany(__filename, __flags, __builtin_va_arg_pack());
      |            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
C:/msys64/mingw64/include/io.h:413:10: error: invalid use of '__builtin_va_arg_pack ()'
  413 |   return __mingw_call__open(__filename, __flags, __builtin_va_arg_pack());
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In function '_sopen',
    inlined from 'sopen' at C:/msys64/mingw64/include/io.h:480:10:
C:/msys64/mingw64/include/io.h:425:7: error: invalid use of '__builtin_va_arg_pack_len ()'
  425 |   if (__builtin_va_arg_pack_len() > 1)
      |       ^~~~~~~~~~~~~~~~~~~~~~~~~~~
C:/msys64/mingw64/include/io.h:426:12: error: invalid use of '__builtin_va_arg_pack ()'
  426 |     return __mingw_call__sopen_warn_toomany(__filename, __flags, __share, __builtin_va_arg_pack());
      |            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
C:/msys64/mingw64/include/io.h:431:10: error: invalid use of '__builtin_va_arg_pack ()'
  431 |   return __mingw_call__sopen(__filename, __flags, __share, __builtin_va_arg_pack());
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
make[2]: *** [Makefile:370: celtdec.o] Error 1

[lazka]

This comes down to:

// a.c
#include <io.h>

$ gcc -c a.c -D_FORTIFY_SOURCE=2 -O2
In file included from a.c:4:
C:/msys64/ucrt64/include/io.h: In function '_open':
C:/msys64/ucrt64/include/io.h:407:7: error: invalid use of '__builtin_va_arg_pack_len ()'
  407 |   if (__builtin_va_arg_pack_len() > 1)
...

[mstorsjo]

This comes down to:

// a.c
#include <io.h>

$ gcc -c a.c -D_FORTIFY_SOURCE=2 -O2
In file included from a.c:4:
C:/msys64/ucrt64/include/io.h: In function '_open':
C:/msys64/ucrt64/include/io.h:407:7: error: invalid use of '__builtin_va_arg_pack_len ()'
  407 |   if (__builtin_va_arg_pack_len() > 1)
...

Now this is weird. I tried this in an UCRT64 environment (fully upgraded) and I don't get any error with this input file and this exact command. Is there perhaps some file that does get included optionally if it exists (and/or gets included before some other file, if some package is installed), changing how things behave in your case?

Can you get me the output of gcc a.c -D_FORTIFY_SOURCE=2 -O2 -E -dD? Then I can compare that with the output from my installation, and see what differs.

[lazka]

uh, you're right, I mixed things up somehow, sorry:

#define __attribute__(x)
#include <io.h>

which comes from https://gitlab.xiph.org/xiph/celt/-/blob/e18de7747fb1655e66bf8d291560587036bfe53c/tools/wave_out.h#L73
same for speex: https://gitlab.xiph.org/xiph/speex/-/blob/5b036b2ca5e27004502e67ee20490a16f5e68aa1/src/wave_out.h#L45

so that's kinda expected to fail I guess. Those files are only included under Windows, so the code was likely trying to port to MSVC via macro hackery without taking mingw into account.

I'll try to fix this upstream.

[mstorsjo]

uh, you're right, I mixed things up somehow, sorry:

#define __attribute__(x)
#include <io.h>

Oh - no wonder that will break, yeah. I think I've run into such code elsewhere at some other point too. By doing that, essentially all bets are off how things work - it's a wonder nothing else has broken so far.

so that's kinda expected to fail I guess. Those files are only included under Windows, so the code was likely trying to port to MSVC via macro hackery without taking mingw into account.

Yup, that sounds plausible. Thanks for fixing!

[lazka]

I've created two MRs upstream:

• https://gitlab.xiph.org/xiph/speex/-/merge_requests/9
• https://gitlab.xiph.org/xiph/celt/-/merge_requests/1