typedef.m4 revision 8cfa702f803c5ef6a2b062a489a1b2cf66b45b5e 
1dnl AX_CHECK_TYPEDEF(typedef_name, type, action-if-true, action-if-false)
2dnl exec action-if-true if typedef_name is a typedef to type else exec 
3dnl action-if-false
4dnl currently work only with type typedef'ed in stddef.h
5AC_DEFUN([AX_CHECK_TYPEDEF], [
6dnl AC_LANG_PUSH(C) not in autoconf 2.13
7AC_LANG_SAVE
8AC_LANG_C
9SAVE_CFLAGS=$CFLAGS
10CFLAGS="-Werror $CFLAGS"
11
12AC_TRY_COMPILE(
13  [
14  #include <stddef.h>
15  ],
16  [
17  typedef void (*fct1)($1);
18  typedef void (*fct2)($2);
19  fct1 f1 = 0;
20  fct2 f2 = 0;
21  if (f1 == f2) {}
22  ],
23[$3],[$4])
24
25CFLAGS=$SAVE_CFLAGS
26AC_LANG_RESTORE
27])
28
29
30dnl AX_TYPEDEFED_NAME(typedef_name, candidate_list, var_name)
31dnl set var_name to the typedef name of $1 which must be in canditate_list
32dnl else produce a fatal error
33AC_DEFUN([AX_TYPEDEFED_NAME], [
34	AC_MSG_CHECKING([type of $1])
35	for f in $2; do
36		AX_CHECK_TYPEDEF($1, $f, $3="$f", $3="")
37		if test -n "${$3}"; then
38			break
39		fi
40	done
41	if test -n "${$3}"; then
42		AC_MSG_RESULT([${$3}])
43	else
44		AC_MSG_ERROR([not found])
45	fi
46])
47