translate-c fails to include xkbcommon/xkbcommon.h on ReleaseSafe specifically

[JodiJodington]

Zig Version

0.16.0-dev.731+958faa703

Steps to Reproduce and Observed Behavior

have the file foo.zig:

pub fn main() !void {
    _ = c;
}

const c = @cImport({
    @cInclude("xkbcommon/xkbcommon.h");
});

run it with zig run foo.zig -lc -ODebug (works)
run it with zig run foo.zig -lc -OReleaseFast (works)
run it with zig run foo.zig -lc -OReleaseSafe and get:

foo.zig:5:11: error: C import failed
const c = @cImport({
          ^~~~~~~~
referenced by:
    main: foo.zig:2:9
    callMain [inlined]: zig/zig-x86_64-linux-0.16.0-dev.731+958faa703/lib/std/start.zig:627:37
    callMainWithArgs [inlined]: zig/zig-x86_64-linux-0.16.0-dev.731+958faa703/lib/std/start.zig:587:20
    main: zig/zig-x86_64-linux-0.16.0-dev.731+958faa703/lib/std/start.zig:602:28
    1 reference(s) hidden; use '-freference-trace=5' to see all references
error: translation failure
/usr/include/bits/stdio2.h:32:7: error: use of unknown builtin '__builtin_va_arg_pack'
      __va_arg_pack ());
      ^

Expected Behavior

I expect it to compile with no errors, just as it did for Debug and ReleaseFast

[JodiJodington]

might be helpful:
/usr/include/std/bits/stdio2.h looks like this around line 32:

#ifdef __va_arg_pack
__fortify_function int
__NTH (sprintf (char *__restrict __s, const char *__restrict __fmt, ...))
{
  return __builtin___sprintf_chk (__s, __USE_FORTIFY_LEVEL - 1,
				  __glibc_objsize (__s), __fmt,
				  __va_arg_pack ());
}

so somehow __va_arg_pack must be being defined on ReleaseSafe but not any of the other modes, all while the compiler does not recognize that the __va_arg_pack builtin exists 😅

[JodiJodington]

@cUndef("__va_arg_pack") right before @cInclude("xkbcommon/xkbcommon.h") seems to work as a temporary fix

[IntegratedQuantum]

I also just stumbled over this. It affects all headers that include stdio.h and it fails both on Windows (where the failure is in stdio.h) and on Linux.

@cUndef("__va_arg_pack") right before @Cinclude("xkbcommon/xkbcommon.h") seems to work as a temporary fix

That did not work for me in 0.16.0-dev.1424+d3e20e71b, but I found that on Linux I could get away with just defining the header guard @cDefine("_BITS_STDIO2_H", ""); since none of the functions from that header seem to actually be used in the dependent header files.