Re: question about whether to set CFLAGS in configure.ac

[Bob Friesenhahn]

On Thu, 1 Dec 2005, Brian Lloyd wrote:
> >
> Try this.
>
> saved_CFLAGS=$CFLAGS
> CFLAGS="$CFLAGS -I$(HDF5DIR)/include -L$(HDF5DIR)/lib"
> >    AC_CHECK_LIB([hdf5], [H5Fflush], [], [nc_hdf5_lib_missing=yes])
> CFLAGS=$saved_CFLAGS
>
> This gives the needed CFLAGS for the CHECK_LIB function, but leaves the
> CFLAGS variable set as it was before this call.

Any -I options should be appended to CPPFLAGS and any -L options 
should be appended to LDFLAGS.  While the approach of temporarily 
updating a variable is the right one, this example is improperly using 
CFLAGS.

Bob
======================================
Bob Friesenhahn
address@hidden, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/