Re: Problem with tests for GSL

[Brian Dessent]

Laurence Finston wrote:

> However, I think the problem was that the
> location of the library is not in the "system search path", which is why I
> need the options I mentioned in my original posting.  I'm not the system
> administrator on this machine and I can't do anything about changing this.
> I haven't found any way of passing this information to Autoconf so it can
> use these options when testing for the presence of the library and I
> didn't find any discussion of this problem in the places I looked
> before.

People have already pointed you at how to write a configure test that
sets its own *FLAGS for the duration of the test.  But I'm confused, if
your installation of GSL is in a strange place then why would you want
to hard-code something like that into the package's configure.ac file? 
Shouldn't you instead just leave the configure test to use the standard
autoconf variables and instead configure your package with:

path/to/configure --some-options \
   CPPFLAGS="-I/my/custom/gsl/location/include" \
   LDFLAGS="-L/my/custom/gsl/location/lib"

All of these *FLAGS are meant to be settable this way by the user when
invoking configure if they have special needs, such as non-standard
locations.  You don't need to modify any files to achieve that.

Brian