[EMAIL PROTECTED] wrote:
>
> On Sat, Oct 13, 2001 at 11:24:57AM -0700, Paul Eggert wrote:
> > > From: [EMAIL PROTECTED]
> > > Date: Sat, 13 Oct 2001 10:22:31 -0700
> > >
> > > AC_MSG_CHECKING([whether $CC accepts C99 declarations])
> > > AC_TRY_COMPILE([],[
> > > int x=0; x+=1; int y=0;
> > > for (int z=0; z < 2; z++);
> > > ],[
> > > AC_MSG_RESULT(yes)
> > > ],
> > > [
> > > AC_MSG_ERROR([
> > > *** This package requires a C99 compiler.])
> > > ])
> >
> > OK, but why bother with that? Just run 'make'. If it fails, your
> > compiler doesn't support C99 declarations. I see little need to
> > discover that at 'configure'-time.
>
> At least i can guess the "-std=gnu99" option if CC=gnu .. ?
make a macro (after AC_PROG_CC) that includes a check like
TESTC99DECLARATIONS
if notOK and test $GCC = yes ::
save_CFLAGS="$CFLAGS"
CFLAGS="$CFLAGS -std=gnu99"
TESTC99DECLARATIONS
if stillnotOK ::
CFLAGS=save_CFLAGS ; echo BAD (or bail out)
else
echo "OK (with -std=gnu99)"
fi
else
echo BAD (or bail out)
fi
get the idea? :-)
>
> > Now, if your goal was to find a C compiler tht supported C99
> > declarations, that would be another story.
>
> Yah, that's my goal.
>
> > Or if your goal was to define a macro that is nonzero if C99
> > declarations are supported, Autoconf could do that too. But I don't
> > think a macro like that would be all that useful in practice: it'd
> > just make the code uglier.
>
> No, that's silly. i'm not going to litter my code with #ifdefs
> for old compilers. More realistically, i just want configure to
> suggest upgrading gcc if the installed gcc doesn't support C99.
> Something like that.
>
however you will notice that many many compilers out there do not
support your style - atleast not now. Your code is not (yet) quite
portable but making it portable atleast throughout gcc makes still
fine for a good share of computer space. I support what Pauls remark
points at but then again, you can use autoconf to detect differences
on platforms that have a gcc... and there are surely quite some..:-O
cheers,
-- guido Edel sei der Mensch, hilfreich und gut
GCS/E/S/P C++$++++ ULHS L++w- N++@ d(+-) s+a- r+@>+++ y++ 5++X- (geekcode)
