mirror of
https://git.postgresql.org/git/postgresql.git
synced 2024-12-09 08:10:09 +08:00
97 lines
3.0 KiB
Plaintext
97 lines
3.0 KiB
Plaintext
# Macros to detect C compiler features
|
|
# $Header: /cvsroot/pgsql/config/c-compiler.m4,v 1.7 2003/04/06 22:45:22 petere Exp $
|
|
|
|
|
|
# PGAC_C_SIGNED
|
|
# -------------
|
|
# Check if the C compiler understands signed types.
|
|
AC_DEFUN([PGAC_C_SIGNED],
|
|
[AC_CACHE_CHECK(for signed types, pgac_cv_c_signed,
|
|
[AC_TRY_COMPILE([],
|
|
[signed char c; signed short s; signed int i;],
|
|
[pgac_cv_c_signed=yes],
|
|
[pgac_cv_c_signed=no])])
|
|
if test x"$pgac_cv_c_signed" = xno ; then
|
|
AC_DEFINE(signed,, [Define to empty if the C compiler does not understand signed types.])
|
|
fi])# PGAC_C_SIGNED
|
|
|
|
|
|
|
|
# PGAC_TYPE_64BIT_INT(TYPE)
|
|
# -------------------------
|
|
# Check if TYPE is a working 64 bit integer type. Set HAVE_TYPE_64 to
|
|
# yes or no respectively, and define HAVE_TYPE_64 if yes.
|
|
AC_DEFUN([PGAC_TYPE_64BIT_INT],
|
|
[define([Ac_define], [translit([have_$1_64], [a-z *], [A-Z_P])])dnl
|
|
define([Ac_cachevar], [translit([pgac_cv_type_$1_64], [ *], [_p])])dnl
|
|
AC_CACHE_CHECK([whether $1 is 64 bits], [Ac_cachevar],
|
|
[AC_TRY_RUN(
|
|
[typedef $1 int64;
|
|
|
|
/*
|
|
* These are globals to discourage the compiler from folding all the
|
|
* arithmetic tests down to compile-time constants.
|
|
*/
|
|
int64 a = 20000001;
|
|
int64 b = 40000005;
|
|
|
|
int does_int64_work()
|
|
{
|
|
int64 c,d;
|
|
|
|
if (sizeof(int64) != 8)
|
|
return 0; /* definitely not the right size */
|
|
|
|
/* Do perfunctory checks to see if 64-bit arithmetic seems to work */
|
|
c = a * b;
|
|
d = (c + b) / b;
|
|
if (d != a+1)
|
|
return 0;
|
|
return 1;
|
|
}
|
|
main() {
|
|
exit(! does_int64_work());
|
|
}],
|
|
[Ac_cachevar=yes],
|
|
[Ac_cachevar=no],
|
|
[# If cross-compiling, check the size reported by the compiler and
|
|
# trust that the arithmetic works.
|
|
AC_COMPILE_IFELSE([AC_LANG_BOOL_COMPILE_TRY([], [sizeof($1) == 8])],
|
|
Ac_cachevar=yes,
|
|
Ac_cachevar=no)])])
|
|
|
|
Ac_define=$Ac_cachevar
|
|
if test x"$Ac_cachevar" = xyes ; then
|
|
AC_DEFINE(Ac_define,, [Define to 1 if `]$1[' works and is 64 bits.])
|
|
fi
|
|
undefine([Ac_define])dnl
|
|
undefine([Ac_cachevar])dnl
|
|
])# PGAC_TYPE_64BIT_INT
|
|
|
|
|
|
|
|
# PGAC_CHECK_ALIGNOF(TYPE, [INCLUDES = DEFAULT-INCLUDES])
|
|
# -----------------------------------------------------
|
|
# Find the alignment requirement of the given type. Define the result
|
|
# as ALIGNOF_TYPE. This macro works even when cross compiling.
|
|
# (Modelled after AC_CHECK_SIZEOF.)
|
|
|
|
AC_DEFUN([PGAC_CHECK_ALIGNOF],
|
|
[AS_LITERAL_IF([$1], [],
|
|
[AC_FATAL([$0: requires literal arguments])])dnl
|
|
AC_CHECK_TYPE([$1], [], [], [$2])
|
|
AC_CACHE_CHECK([alignment of $1], [AS_TR_SH([pgac_cv_alignof_$1])],
|
|
[if test "$AS_TR_SH([ac_cv_type_$1])" = yes; then
|
|
_AC_COMPUTE_INT([((char*) & pgac_struct.field) - ((char*) & pgac_struct)],
|
|
[AS_TR_SH([pgac_cv_alignof_$1])],
|
|
[AC_INCLUDES_DEFAULT([$2])
|
|
struct { char filler; $1 field; } pgac_struct;],
|
|
[AC_MSG_ERROR([cannot compute alignment of $1, 77])])
|
|
else
|
|
AS_TR_SH([pgac_cv_alignof_$1])=0
|
|
fi])dnl
|
|
AC_DEFINE_UNQUOTED(AS_TR_CPP(alignof_$1),
|
|
[$AS_TR_SH([pgac_cv_alignof_$1])],
|
|
[The alignment requirement of a `$1'.])
|
|
])# PGAC_CHECK_ALIGNOF
|