diff --git a/src/runtime/defs_plan9_386.go b/src/runtime/defs_plan9_386.go
index 170506b..212ecdf 100644
--- a/src/runtime/defs_plan9_386.go
+++ b/src/runtime/defs_plan9_386.go
@@ -1,5 +1,7 @@
 package runtime
 
+const _PAGESIZE = 0x1000
+
 type ureg struct {
 	di    uint32 /* general registers */
 	si    uint32 /* ... */