diff --git a/src/if_ruby.c b/src/if_ruby.c
index 06465bd5a7..9301b72927 100644
--- a/src/if_ruby.c
+++ b/src/if_ruby.c
@@ -418,7 +418,8 @@ VALUE rb_num2ulong(VALUE x)
 #  endif
 # endif
 
-# if defined(USE_RGENGC) && USE_RGENGC
+   /* Do not generate a prototype here, VALUE isn't always defined. */
+# if defined(USE_RGENGC) && USE_RGENGC && !defined(PROTO)
 void rb_gc_writebarrier_unprotect_promoted_stub(VALUE obj)
 {
     return dll_rb_gc_writebarrier_unprotect_promoted(obj);
diff --git a/src/version.c b/src/version.c
index 89272be506..f2b1ca7c5a 100644
--- a/src/version.c
+++ b/src/version.c
@@ -741,6 +741,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    511,
 /**/
     510,
 /**/