1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
|
dnl AC_C_ATTRIBUTE_PACKED
dnl set ATTRIBUTE_PACKED if this is supported
AC_DEFUN([AC_C_ATTRIBUTE_PACKED],
[AC_CACHE_CHECK([__attribute__ ((packed)) support],
[ac_cv_c_attribute_packed],
[AC_TRY_COMPILE([],
[static struct { int a; } __attribute__ ((packed)) c = {0};],
[ac_cv_c_attribute_packed=yes],
[ac_cv_c_attribute_packed=no])
])
if test x"$ac_cv_c_attribute_packed" = x"yes"; then
ATTRIBUTE_PACKED="__attribute__ ((packed))"
fi])
dnl The following AC macros are from mpeg2dec.
dnl Written by Michel Lespinasse <walken@zoy.org>
dnl AC_C_ATTRIBUTE_ALIGNED
dnl define ATTRIBUTE_ALIGNED_MAX to the maximum alignment if this is supported
AC_DEFUN([AC_C_ATTRIBUTE_ALIGNED],
[AC_CACHE_CHECK([__attribute__ ((aligned ())) support],
[ac_cv_c_attribute_aligned],
[ac_cv_c_attribute_aligned=0
for ac_cv_c_attr_align_try in 2 4 8 16 32 64; do
AC_TRY_COMPILE([],
[static char c __attribute__ ((aligned($ac_cv_c_attr_align_try))) = 0; return c;],
[ac_cv_c_attribute_aligned=$ac_cv_c_attr_align_try])
done])
if test x"$ac_cv_c_attribute_aligned" != x"0"; then
AC_DEFINE_UNQUOTED([ATTRIBUTE_ALIGNED_MAX],
[$ac_cv_c_attribute_aligned],[maximum supported data alignment])
fi])
dnl AC_TRY_CFLAGS (CFLAGS, [ACTION-IF-WORKS], [ACTION-IF-FAILS])
dnl check if $CC supports a given set of cflags
AC_DEFUN([AC_TRY_CFLAGS],
[AC_MSG_CHECKING([if $CC supports $1 flags])
SAVE_CFLAGS="$CFLAGS"
CFLAGS="$1"
AC_TRY_COMPILE([],[],[ac_cv_try_cflags_ok=yes],[ac_cv_try_cflags_ok=no])
CFLAGS="$SAVE_CFLAGS"
AC_MSG_RESULT([$ac_cv_try_cflags_ok])
if test x"$ac_cv_try_cflags_ok" = x"yes"; then
ifelse([$2],[],[:],[$2])
else
ifelse([$3],[],[:],[$3])
fi])
|
