diff --git a/src/lib9/fmt/plan9.h b/src/lib9/fmt/plan9.h
index f9762889..22fa7f0c 100644
--- a/src/lib9/fmt/plan9.h
+++ b/src/lib9/fmt/plan9.h
@@ -1,3 +1,5 @@
+#include <stdint.h>
+
 /*
  * compiler directive on Plan 9
  */
@@ -14,12 +16,15 @@
 #define ulong	_fmtulong
 #define vlong	_fmtvlong
 #define uvlong	_fmtuvlong
+#define uintptr	_fmtuintptr
+
 typedef unsigned char		uchar;
 typedef unsigned short		ushort;
 typedef unsigned int		uint;
 typedef unsigned long		ulong;
 typedef unsigned long long	uvlong;
 typedef long long		vlong;
+typedef uintptr_t uintptr;
 
 /*
  * nil cannot be ((void*)0) on ANSI C,