--- build/configure.ac.warnings.ORIG	2014-07-16 17:33:31.532135893 +0200
+++ build/configure.ac.warnings	2014-07-16 17:49:44.546172432 +0200
@@ -42,13 +42,18 @@
   AS_HELP_STRING([--disable-lto],
                  [Do not try to use Link-Time Optimization]))
 if test "x$enable_lto" != "xno"; then
-   safe_MAYBE_WARN="$MAYBE_WARN"
-   MAYBE_WARN="$MAYBE_WARN -flto"
-   AC_TRY_LINK([],[
-	int main(int argc, char **argv) { return 0; }
-   ],[],[
-	MAYBE_WARN="$safe_MAYBE_WARN"
-   ])
+AC_ARG_ENABLE(lto,
+  AS_HELP_STRING([--disable-lto],
+		 [Do not try to use Link-Time Optimization]))
+if test "x$enable_lto" != "xno"; then
+  safe_MAYBE_WARN="$MAYBE_WARN"
+  MAYBE_WARN="$MAYBE_WARN -flto"
+  AC_TRY_LINK([],[
+       int main(int argc, char **argv) { return 0; }
+  ],[],[
+       MAYBE_WARN="$safe_MAYBE_WARN"
+  ])
+fi
 fi
 
 MAYBE_WARN="$MAYBE_WARN -fno-strict-aliasing -fno-common"