diff --git a/ext/sysvshm/php_sysvshm.h b/ext/sysvshm/php_sysvshm.h
index 02e6a034c17..5089bd617fe 100644
--- a/ext/sysvshm/php_sysvshm.h
+++ b/ext/sysvshm/php_sysvshm.h
@@ -17,7 +17,7 @@
 #ifndef PHP_SYSVSHM_H
 #define PHP_SYSVSHM_H
 
-#if HAVE_SYSVSHM
+#ifdef HAVE_SYSVSHM
 
 extern zend_module_entry sysvshm_module_entry;
 #define sysvshm_module_ptr &sysvshm_module_entry
diff --git a/ext/sysvshm/sysvshm.c b/ext/sysvshm/sysvshm.c
index 36c846ea320..dbdeaa0eb1a 100644
--- a/ext/sysvshm/sysvshm.c
+++ b/ext/sysvshm/sysvshm.c
@@ -20,7 +20,7 @@
 
 #include "php.h"
 
-#if HAVE_SYSVSHM
+#ifdef HAVE_SYSVSHM
 
 #include <errno.h>