diff --git a/configure.ac b/configure.ac
index ec936897c1e2dcb7c1e94ff87ae052661ad8b8c4..e4b035e233266436c668a3bc075e2caca69f57ee 100644
--- a/configure.ac
+++ b/configure.ac
@@ -4,10 +4,10 @@
 #  autoconf 2.69
 #  libtool  2.4.6
 
-AC_PREREQ([2.69])
+AC_PREREQ([2.70])
 LT_PREREQ([2.4.6])
 
-AC_INIT([cdi], [1.9.10], [https://mpimet.mpg.de/cdi])
+AC_INIT([cdi],[1.9.10],[https://mpimet.mpg.de/cdi])
 
 AC_DEFINE_UNQUOTED(CDI, ["$PACKAGE_VERSION"], [CDI version])
 
@@ -27,7 +27,7 @@ AC_CONFIG_HEADERS([src/config.h])
 AM_MAINTAINER_MODE([disable])
 
 # Check building environment
-AC_PROG_CC_C99
+AC_PROG_CC
 dnl The check above forgets to delete the following directory
 dnl generated by the MacOS linker, which results in multiple
 dnl annoying messages from the rm utility:
@@ -439,10 +439,11 @@ AC_CONFIG_FILES([tests/test_cksum_grib \
                  tables/gen_tableheaderfile \
                  util/serialrun],[chmod a+x "$ac_file"])
 
-AC_OUTPUT([Makefile src/Makefile interfaces/Makefile app/Makefile \
+AC_CONFIG_FILES([Makefile src/Makefile interfaces/Makefile app/Makefile \
 	tests/Makefile examples/Makefile cdi.settings \
 	examples/pio/Makefile src/pkgconfig/cdi.pc src/pkgconfig/cdipio.pc \
         src/pkgconfig/cdi_f2003.pc])
+AC_OUTPUT
 
 #  ----------------------------------------------------------------------
 #  Show configuration