[Freeciv-Dev] Re: (PR#4130) Compile problems on Solaris 9

["Jason Short" <jdorje@xxxxxxxxxxxxxxxxxxxxx>]

Mike Kaufman wrote:
> I have this problem on my linux box as well. Here's my fix:

> Index: configure.ac
> ===================================================================
> RCS file: /home/freeciv/CVS/freeciv/configure.ac,v
> retrieving revision 1.43
> diff -u -r1.43 configure.ac
> --- configure.ac      2003/05/13 21:10:32     1.43
> +++ configure.ac      2003/05/18 00:41:23
> @@ -346,8 +346,8 @@
>  You may need to install a zlib \"development\" package.]))
>  
>      dnl Check for libpng
> -    AC_CHECK_LIB(png, png_read_image, [X_LIBS="$X_LIBS -lpng"],
> -     AC_MSG_ERROR([Could not find PNG library (libpng).]), [-lz])
> +    AC_CHECK_LIB(png, png_read_image, [X_LIBS="$X_LIBS -lpng -lm"],
> +     AC_MSG_ERROR([Could not find PNG library (libpng).]), [-lm -lz])
>      AC_CHECK_HEADER(png.h, ,
>       AC_MSG_ERROR([libpng found but not png.h.
>  You may need to install a libpng \"development\" package.]))

Two possible problems:

1.  If libm isn't present at all, you'll be told that you need libpng.
2.  If libm isn't needed, you'll link against it unnecessarily.

The only really bad situation would be where #1 and #2 were both true: 
i.e., on platforms that don't use libm at all.  Is this ever the case? 
Who is familiar with libpng?

The patch is at least better than the current situation, which we *know* 
fails sometime.  So if we can't do any better it should go in.

jason