m4: iovec.m4 - Modernize m4 syntax

diff --git a/m4/iovec.m4 b/m4/iovec.m4
index a1f3b485582d141e3f87bfb2fbd5424237ed920e..90e2d0ae9708b31ae80835bfdfa9ae9abe707acc 100644 (file)
--- a/m4/iovec.m4
+++ b/m4/iovec.m4
@@ -1,7 +1,6 @@
 dnl * do we have struct iovec
 AC_DEFUN([DOVECOT_IOVEC], [
-  AC_MSG_CHECKING([for struct iovec])
-  AC_CACHE_VAL(i_cv_struct_iovec,
+  AC_CACHE_CHECK([for struct iovec], i_cv_struct_iovec,
   [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
   #include <sys/types.h>
   #include <sys/uio.h>
@@ -9,9 +8,8 @@ AC_DEFUN([DOVECOT_IOVEC], [
   [[struct iovec *iovec;]])],
   [i_cv_struct_iovec=yes],
   [i_cv_struct_iovec=no])])
-  
-  if test $i_cv_struct_iovec = yes; then
+
+  AS_IF([test $i_cv_struct_iovec = yes], [
           AC_DEFINE(HAVE_STRUCT_IOVEC,, [Define if you have struct iovec])
-  fi
-  AC_MSG_RESULT($i_cv_struct_iovec) 
+  ])
 ])