configure.ac: Made some changes to void warnings with modern automake versions

diff --git a/configure.ac b/configure.ac
index c438abf..f9d7538 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -3,7 +3,7 @@ AC_INIT([EXIF library], [0.6.21.1], [libexif-devel@lists.sourceforge.net], [libe
 AC_CONFIG_SRCDIR([libexif/exif-data.h])
 AC_CONFIG_HEADERS([config.h])
 AC_CONFIG_MACRO_DIR([auto-m4])
-AM_INIT_AUTOMAKE([-Wall gnu 1.9 dist-bzip2 dist-zip check-news])
+AM_INIT_AUTOMAKE([-Wall gnu 1.9 dist-bzip2 dist-zip check-news subdir-objects])
 AM_MAINTAINER_MODE
 
 # Use the silent-rules feature when possible.
@@ -70,10 +70,11 @@ AC_SUBST([LIBEXIF_CURRENT_MIN],[`expr $LIBEXIF_CURRENT - $LIBEXIF_AGE`])
 LIBEXIF_VERSION_INFO="$LIBEXIF_CURRENT:$LIBEXIF_REVISION:$LIBEXIF_AGE"
 AC_SUBST([LIBEXIF_VERSION_INFO])
 
-AC_PROG_CC
+AM_PROG_CC_C_O
 AC_C_CONST
 AC_C_INLINE
 dnl FIXME: AC_LIBTOOL_WIN32_DLL
+AM_PROG_AR
 AM_PROG_LIBTOOL
 AM_CPPFLAGS="$CPPFLAGS"
 GP_CONFIG_MSG([Compiler],[${CC}])
@@ -119,25 +120,23 @@ dnl ---------------------------------------------------------------------------
 LIBS_orig="$LIBS"
 LIBS="$LIBS -lm"
 AC_MSG_CHECKING([for math functions in libm])
-AC_LINK_IFELSE([
-       #include <math.h>
-       int main() {
-         double s = sqrt(0);
-         double p = pow(s,s);
-         return (int)p;
-       }
-], [AC_MSG_RESULT(yes)], [
+AC_LINK_IFELSE([AC_LANG_PROGRAM([
+         #include <math.h>
+         ],[
+           double s = sqrt(0);
+           double p = pow(s,s);
+         ])],
+       [AC_MSG_RESULT(yes)], [
        AC_MSG_RESULT(no)
        LIBS="$LIBS_orig"
        AC_MSG_CHECKING([for math functions without libm])
-       AC_LINK_IFELSE([
+       AC_LINK_IFELSE([AC_LANG_PROGRAM([
                #include <math.h>
-               int main() {
+               ],[
                  double s = sqrt(0);
                  double p = pow(s,s);
-                 return (int)p;
-               }
-       ], [
+               ])],
+       [
                AC_MSG_RESULT(yes)
        ],[
                AC_MSG_RESULT(no)