Wesley Smith <wesley.hoke@xxxxxxxxx> writes: > For 64bit builds, I need to #define x86_64 for a lib I'm using. It has > nothing to do with the size of longs from my perspective, but whether > the binary is compiled for a 64 or 32 bit target. I think what everyone is struggling with here is that you're asking a question that seems straightforward to you, but which from a portability perspective is not a valid question. There are no simple "64-bit" or "32-bit" labels that you can apply to things. Do you mean the size of a pointer? The size of a long? The size of size_t? The native word size of the underlying hardware? Or is that question being used as a proxy for whether the processor supports an x86_64 instruction set? I suspect that you're dealing with "all the world is Linux" code, and therefore doing something like: AC_CHECK_SIZEOF([long]) AS_IF([test "$ac_cv_sizeof_long" -eq 8], [AC_DEFINE([OSBIT], 64, [Define to the size of a long in bits.])], [AC_DEFINE([OSBIT], 32, [Define to the size of a long in bits.])]) would do what you want, but you won't find something exactly like that built into Autoconf since it's not generally a meaningful thing to do on a broader variety of platforms. -- Russ Allbery (rra@xxxxxxxxxxxx) <http://www.eyrie.org/~eagle/> _______________________________________________ Autoconf mailing list Autoconf@xxxxxxx http://lists.gnu.org/mailman/listinfo/autoconf