O.K. Now I removed that test from configure, but then it failed when checking for cpuid.h
While searching for it, I found that gcc has bunch of includes in /usr/lib64/gcc/x86_64-pc-linux-gnu/4.5.1/include
It seems that all headers are just definitions of small inline and handwritten assembly codes.
I couldn't find equivalents in open64, so only way is to tweak those for open64, I suppose ?
I would expect to get at least stuff like limits.h, but there is nothing like that to be found in open64...
Open64 compiler uses GNU binutils, please refer section 4 of the ReleaseNotes.txt for supported version details. Open64 does support relro, but the way 'configure' script tests this feature is not.
Will get back soon on other issues.