Re: Possible bug - AC_PROG_CC

[Ralf Wildenhues]

Hello Michael,

* Michael Ambrus wrote on Thu, Dec 07, 2006 at 05:18:05PM CET:
> It seems that AC_PROG_CC misbehaves if used inside a if-case, in which it
> doesn't detects whether or not we try to use a cross compiler (and
> $cross_compiling is not set to "yes"). In the example below, $USECPLUSPLUS
> is "no" in both cases which is intentional.

Yep.  The first compiler macro that is invoked
(AC_PROG_{CC,CXX,F77,FC,OBJC}) must be invoked unconditionally.
We've had a couple of reports about this, I think we should document
it for now.  Fixing it is quite intricate.

> I'm not certain which version of autoconf is used since both autoconf2.13and
> autoconf2.50 are installed on my system.
> 
> configure.in contains AC_PREREQ([2.59]), but if I try to set this to 2.13 I
> get all sorts of other errors. Setting it to 2.50 produces the same as
> mentioned above.
> 
> 'autoconf -V' will respond 2.50 however...

Then most likely the system has installed a wrapper that is a bit smart:
when it sees a configure.ac file (or a configure.in file that has
AC_PREREQ([2.50+])) then it will invoke the newer version.

Cheers,
Ralf