> From: Dale E Martin <[EMAIL PROTECTED]>
> Date: Thu, 5 Jul 2001 14:21:36 -0400
>
> Would it make sense for autoconf to have a macro to define all of
> the available native types for the language it supports? Or is this
> a fairly unique bit of information to require?
In C99, the "right" way to see whether you have a 64-bit type is like
this:
#include <stdint.h>
#ifdef INT64_MAX
/* There is a type int64_t. */
#else
/* There is no such type, but 'long long' is longer than 64-bit. */
#endif
You can also include <inttypes.h> instead of <stdint.h>; this tends to
work better in practice with pre-C99 hosts, but <inttypes.h> drags in
more stuff and C99 does not require it for standalone compilers.
It might be nice to autoconfize this somehow, so that your source code
would look like this:
#if HAVE_CONFIG_H
# include <config.h> /* define INT64_MAX, int64_t, etc. if needed */
#endif
#if HAVE_INTTYPES_H
# include <inttypes.h>
#else
# if HAVE_STDINT_H
# include <stdint.h>
# endif
#endif
#ifdef INT64_MAX
/* There is a type int64_t. */
#else
/* There is no such type, but 'long long' is longer than 64-bit. */
#endif
That shouldn't take too much work -- perhaps you'd like to take a stab
at an autoconf macro to do that?
There is no easy way in C99 to iterate through all the integer type
widths. I don't offhand see how to solve that problem
straightforwardly with autoconf, unfortunately.
