Ok, here as Roy requested: We do commit then review/fixing. So, here is the

first cut for a fixed C header file check:

| Fix the recently introduced C header file checking: We now use the C
| pre-processor pass only (and no longer the complete compiler pass) to
| determine whether a C header file exists or not. Because only this way we're
| safe against inter-header dependencies (which caused horrible portability
| problems). The only drawback is that we now have a CPP configuration variable
| which has to be determined first (we do a similar approach as GNU Autoconf
| does here). When all fails the user still has the possibility to override it
| manually via APACI or src/Configuration.  As a fallback for the header check
| itself we can directly check the existance of the file under /usr/include,
| too.

Please try it out, fix it, grep out the PR-numbers, etc.
Cleanups and other stuff for src/helpers/* I'll do tomorrow.
Today I've totally tired and have to go to bed...


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@82052 13f79535-47bb-0310-9956-ffa450edef68