diff --git a/src/tools/jam/hcache.c b/src/tools/jam/hcache.c
index 54a3bd8170..9e846a70aa 100644
--- a/src/tools/jam/hcache.c
+++ b/src/tools/jam/hcache.c
@@ -13,6 +13,7 @@
 # include "hcache.h"
 # include "variable.h"
 # include "search.h"
+# include "pathsys.h"
 
 #ifdef OPT_HEADER_CACHE_EXT