diff --git a/toolbox/grep/util.c b/toolbox/grep/util.c
index 497db060d..5712feeac 100644
--- a/toolbox/grep/util.c
+++ b/toolbox/grep/util.c
@@ -273,7 +273,7 @@ procfile(const char *fn)
 	return (c);
 }
 
-#define iswword(x)	(iswalnum((x)) || (x) == L'_')
+#define iswword(x)	(iswalnum((wint_t)(x)) || (x) == L'_')
 
 /*
  * Processes a line comparing it with the specified patterns.  Each pattern
@@ -323,7 +323,7 @@ procline(struct str *l, int nottext)
 				continue;
 			/* Check for whole word match */
 			if (fg_pattern[i].word && pmatch.rm_so != 0) {
-				wint_t wbegin, wend;
+				wchar_t wbegin, wend;
 
 				wbegin = wend = L' ';
 				if (pmatch.rm_so != 0 &&