I've had some trouble with graphics/jasper 1.900.1.
Jasper turns out to be pretty important.
Packages I need that depend on it directly or indirectly
include ghostscript, netpbm, groff, ncurses, sendmail, and of course anything that depends on these.

On my first attempt at building packages, it compiled transparently,
so I was very surprised when today it was getting a compiler error.
I was thinking of looking a little closer at the compiler error, but 
then I remembered that it was probably compiled before with gcc Version 2.95.3.  

So I thought I would at least verify that it worked under 2.95.3.
Setting the default back, I got an error message
configure: error: C compiler cannot create executables.

At this point I figured that the problem must have been with the new pgsrc tree I downloaded.   There was no point in 
worrying about 2.95.3, so I changed the default back again to 3.3.5.

This time, jasper compiled without a wimper?????????

If there is something I've done different, I don't know what it was.
I'm not sure that I every tried to "bmake" jasper with 3.3.5 from its directory.   Most of the times it failed, it was 
being automatically compiled as a pre-requisite to something else.

Since it compiles now, there's nothing else to be done, but I thought I should post this for anyone who has the same 
problem.