Solaris C header : can't compile PHP

I've just installed Forte 7 (trial version), in aim to get the C compiler (cuz the gcc doesn't work). when i launch ./configure, it works well. But when i launch make, it bugs and say can't find include file : stdio.h, math.h, strings.h ...... i've seen that forte has installed files : sdio.h.SUNWCCh on that directory : /opt/SUNWspro/prod/include Do those files must interract ? In /usr/include, there are very few files and im sure that make search in this directory. I've tried to take C headers from a linux machine, and via FTP putting them in my include directory (after all its only C code !) and its really better. But it craches again : "/usr/include/bits/pthreadtypes.h" : syntax error before or at size_t plizzzzzzz some help !!!!!!