diff --git a/configure.ac b/configure.ac
index a58ca6b7f..10b57bc48 100644
--- a/configure.ac
+++ b/configure.ac
@@ -175,7 +175,7 @@ CITUSAC_PROG_CC_CFLAGS_OPT([-Wendif-labels])
 CITUSAC_PROG_CC_CFLAGS_OPT([-Wmissing-format-attribute])
 CITUSAC_PROG_CC_CFLAGS_OPT([-Wmissing-declarations])
 CITUSAC_PROG_CC_CFLAGS_OPT([-Wmissing-prototypes])
-# CITUSAC_PROG_CC_CFLAGS_OPT([-Wnull-dereference])
+CITUSAC_PROG_CC_CFLAGS_OPT([-Wnull-dereference])
 CITUSAC_PROG_CC_CFLAGS_OPT([-Wduplicated-cond])
 CITUSAC_PROG_CC_CFLAGS_OPT([-Wlogical-op])
 CITUSAC_PROG_CC_CFLAGS_OPT([-Wjump-misses-init])