Re: [Tinycc-devel] __builtin_va_* builtins missing

[Daniel Wingerd]

The problem isn't building TCC against musl, the problem is building
musl using TCC.

git clone git://git.musl-libc.org/musl && cd musl && ./configure
CC=i386-tcc --target=i386 && rm -r src/complex && make
...
i386-tcc -std=c99 -nostdinc -ffreestanding -fexcess-precision=standard
-frounding-math -Wa,--noexecstack -D_XOPEN_SOURCE=700 -I./arch/i386
-I./arch/generic -Iobj/src/internal -I./src/include -I./src/internal
-Iobj/include -I./include  -Os -pipe -fomit-frame-pointer
-fno-unwind-tables -fno-asynchronous-unwind-tables -ffunction-sections
-fdata-sections -march=i486 -mtune=generic
-Werror=implicit-function-declaration -Werror=implicit-int
-Werror=pointer-sign -Werror=pointer-arith  -c -o
obj/src/fcntl/fcntl.o src/fcntl/fcntl.c
src/fcntl/fcntl.c:11: warning: implicit declaration of function
'__builtin_va_start'
src/fcntl/fcntl.c:12: warning: implicit declaration of function
'__builtin_va_arg'
src/fcntl/fcntl.c:12: error: identifier expected
make: *** [Makefile:148: obj/src/fcntl/fcntl.o] Error 1

The problem is that it's va_start is defined in musl's stdarg.h as
__builtin_va_start and the other va_* defines do the same because this
is standard compiler convention.  TCC is the only compiler that
doesn't do this.

Note, this isn't the only issue with TCC (which is why I removed the
directory requiring the complex functions) but it is an issue with a
straightforward solution.

On Wed, Oct 31, 2018 at 5:16 PM avih <address@hidden> wrote:
>
> Do you have a specific issue to build tcc on musl or use va_* with tcc built 
> with musl?
>
> For me, on current Alpine linux (with gcc 8.2) `git clone 
> git://git.or.cz/tinycc && cd tinycc && ./configure --config-musl && make` 
> builds fine, all the tests pass (`make test`), and I've used this tcc (in the 
> past) to build complex programs which use va_* (mpv).
>
> Is there something you're trying to do which you can't? if yes, can you 
> please give exact steps to reproduce? (including the error messages, if any, 
> which you get)
>
>
> On Wednesday, October 31, 2018 10:53 PM, Jan Nieuwenhuizen <address@hidden> 
> wrote:
>
>
> Daniel Wingerd writes:
>
> > I'm working on getting musl to build using TCC and the first problem I
> > encountered was that TCC is missing __builtin_va_* builtins.
>
> I suspect this is on x86_64?  FWIW, I have finally managed to
> bootstrap*) TCC on i686-linux using the Mes C Library and a pretty
> simplistic stdarg+).
>
> Greetings,
> janneke
>
> *) http://joyofsource.com/reduced-binary-seed-bootstrap.html
> +) http://git.savannah.gnu.org/cgit/mes.git/tree/include/stdarg.h
>
> --
> Jan Nieuwenhuizen <address@hidden> | GNU LilyPond http://lilypond.org
> Freelance IT http://JoyofSource.com | Avatar® http://AvatarAcademy.com
>
>
> _______________________________________________
> Tinycc-devel mailing list
> address@hidden
> https://lists.nongnu.org/mailman/listinfo/tinycc-devel
>
>