diff --git a/autogen.sh b/autogen.sh
index 2dbdbeb..21a2553 100755
--- a/autogen.sh
+++ b/autogen.sh
@@ -58,7 +58,7 @@ toplevel_check $srcfile
 
 # aclocal
 if test -f acinclude.m4; then rm acinclude.m4; fi
-tool_run "$aclocal" "-I common/m4 -I m4 $ACLOCAL_FLAGS"
+tool_run "$aclocal" "-I m4 -I common/m4 $ACLOCAL_FLAGS"
 
 tool_run "$libtoolize" "--copy --force"
 tool_run "$autoheader"
diff --git a/m4/introspection.m4 b/m4/introspection.m4
index 589721c..8d1587c 100644
--- a/m4/introspection.m4
+++ b/m4/introspection.m4
@@ -53,6 +53,9 @@ m4_define([_GOBJECT_INTROSPECTION_CHECK_INTERNAL],
     INTROSPECTION_GENERATE=
     INTROSPECTION_GIRDIR=
     INTROSPECTION_TYPELIBDIR=
+    INTROSPECTION_CFLAGS=
+    INTROSPECTION_LIBS=
+    INTROSPECTION_MAKEFILE=
     if test "x$found_introspection" = "xyes"; then
        INTROSPECTION_SCANNER=`$PKG_CONFIG --variable=g_ir_scanner gobject-intro
        INTROSPECTION_COMPILER=`$PKG_CONFIG --variable=g_ir_compiler gobject-int