Hi there,
we have been bitten by the following problem. Autoconf implements AC_C_BIGENDIAN so that it defines WORDS_BIGENDIAN this way:
/* Define WORDS_BIGENDIAN to 1 if your processor stores words with the most significant byte first (like Motorola and SPARC, unlike Intel). */ #if defined AC_APPLE_UNIVERSAL_BUILD # if defined __BIG_ENDIAN__ # define WORDS_BIGENDIAN 1 # endif #else # ifndef WORDS_BIGENDIAN /* # undef WORDS_BIGENDIAN */ # endif #endif
The spaces between `#' and `define' completely spoil AX_PREFIX_CONFIG_H (which otherwise works very well on everything else). Since 'PPL' is our prefix, we want the symbol PPL_WORDS_BIGENDIAN to be defined (and not WORDS_BIGENDIAN).
Now, I don't believe this is a bug of AX_PREFIX_CONFIG_H. In fact we use that feature: by leaving spaces between the `#' and the macro name we "protect" some macros from renaming. And, of course, it is not a bug of Autoconf, since that spaces are normally immaterial.
Still we have a problem. And no workaround because the obvious one does not work (i.e., it does not undefine WORDS_BIGENDIAN):
AH_BOTTOM([ #ifdef WORDS_BIGENDIAN # define PPL_WORDS_BIGENDIAN # undef WORDS_BIGENDIAN #endif ])
Perhaps this (commenting out all #undef's) is a limitation of AX_PREFIX_CONFIG_H.
Any idea how we could solve this problem? Thanks,
Roberto