These are some tests that configure can perform, that look like they might
help somewhat...
- Macro: AC_C_LONG_DOUBLE
If the C compiler supports the `long double' type, define
`HAVE_LONG_DOUBLE'. Some C compilers that do not define
`__STDC__' do support the `long double' type; some compilers that
define `__STDC__' do not support `long double'.
- Macro: AC_CHECK_SIZEOF (TYPE [, CROSS-SIZE])
Define `SIZEOF_UCTYPE' to be the size in bytes of the C (or C++)
builtin type TYPE, e.g. `int' or `char *'. If `type' is unknown
to the compiler, it gets a size of 0. UCTYPE is TYPE, with
lowercase converted to uppercase, spaces changed to underscores,
and asterisks changed to `P'. If cross-compiling, the value
CROSS-SIZE is used if given, otherwise `configure' exits with an
error message.
For example, the call
AC_CHECK_SIZEOF(int *)
defines `SIZEOF_INT_P' to be 8 on DEC Alpha AXP systems.
- Macro: AC_INT_16_BITS
If the C type `int' is 16 bits wide, define `INT_16_BITS'. This
macro is obsolete; it is more general to use
`AC_CHECK_SIZEOF(int)' instead.
- Macro: AC_LONG_64_BITS
If the C type `long int' is 64 bits wide, define `LONG_64_BITS'.
This macro is obsolete; it is more general to use
`AC_CHECK_SIZEOF(long)' instead.
Marc G. Fournier
Systems Administrator @ hub.org
primary: scrappy@hub.org secondary: scrappy@{freebsd|postgresql}.org