Re: Smpeg MMX asm compilation (problem)

[Pedro Alves <pedro_alves at portugalmail dot pt>]

Matt wrote:
> Alright, I've managed to get both .S files to compile- however when I 
> try to link them with a program using:
> extern "C" {
> extern unsigned int cpu_flags(void);
> extern void IDCT_mmx(DCTBLOCK data);
> }
>
> The linker tool comes up with
> ./.libs/libsmpeg.a(parseblock.o): In function `Z8InitIDCTv':
> e:/programming/smpeg/video/parseblock.cpp:117: undefined reference to 
> `cpu_flags()'
> ./.libs/libsmpeg.a(parseblock.o): In function 
> `Z15ParseReconBlockiP10vid_stream':
> e:/programming/smpeg/video/parseblock.cpp:583: undefined reference to 
> `IDCT_mmx(short*)'
>
> They *are* getting assembled&linked- Why is this??
> Here's the code for the mmxflags_asm.S, which should be enough for you 
> folk to figure it out:
> "
> .text
>     .align 2
> .globl cpu_flags
>     .def    cpu_flags;    .scl   2;      .type 32;    .endef
> cpu_flags:
>
> cpu_flags.L1:
>         ret
>
> "
>
> M@

http://www.google.com/search?&q=mixing+assembly+and+c
   8.2.2 Using C Functions in Assembly Procedures
      should give you a hint...

Cheers,
Pedro Alves