diff --git a/configure.ac b/configure.ac
index 59689db..3a1f19a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -8,6 +8,7 @@ AC_CONFIG_MACRO_DIR([m4])
 
 AM_INIT_AUTOMAKE(
   [1.11]
+  [-Wall]
   [foreign]
   [nostdinc]
   [subdir-objects]