RE: [AD] sincos

["Vincent Penquerc'h" <Vincent.Penquerch@xxxxxxxxxx>]

Title: RE: [AD] sincos

> If it's selected on a per-file basis (as I think was suggested on SF
> message thingy) it should be fine.  I wanted it in the past
> too, though
> not right now.

It is.

>        -pipe  Use pipes rather than temporary files for  communi-
>               cation  between  the various stages of compilation.
>               This fails to work on some systems where the assem-
>               bler cannot read from a pipe; but the GNU assembler
>               has no trouble.
>
> I forget where the discussion went after that.  Anyway, it should
> disablable in configure.  And does it really give a speed boost?
> I couldn't tell, I think.

Ah, I remember. I found Peter's reply to my configure patch:

On 21 Nov 2001, Vincent Penquerc'h <Vincent.Penquerch@xxxxxxxxxx> wrote:
> +[AC_MSG_CHECKING(whether assembler can read from a pipe)
> +allegro_save_CFLAGS=$LDFLAGS
                        ^ CFLAGS
> +CFLAGS="-pipe $CFLAGS"
> +AC_CACHE_VAL(allegro_cv_prog_can_use_pipe, [
> +AC_TRY_COMPILE(,int main(){return 0;},allegro_cv_prog_can_use_pipe=yes, allegro_cv_prog_can_use_pipe=no)])
> +LDFLAGS=$allegro_save_CFLAGS
   ^ CFLAGS
> +AC_MSG_RESULT($allegro_cv_prog_can_use_pipe)
> +])

(for whoever's to commit it)

(that is, I had confused up CFLAGS/LDFLAGS)

As for the speed boost, it can be felt on large compiles. And
when /tmp runs low, it allows one to compile very large files,
which would fail without -pipe (say, C files filled with huge
data arrays coded for a certain competition ...)

--
Vincent Penquerc'h