diff --git a/tools/wrc/genres.c b/tools/wrc/genres.c
index 7871c793ac4..3d401804148 100644
--- a/tools/wrc/genres.c
+++ b/tools/wrc/genres.c
@@ -1741,23 +1741,8 @@ char *prep_nid_for_label(const name_id_t *nid)
 */
 char *make_c_name(const char *base, const name_id_t *nid, const language_t *lan)
 {
-	int nlen;
-	char *buf;
-	char *ret;
-	char lanbuf[6];
-
-	sprintf(lanbuf, "%d", lan ? MAKELANGID(lan->id, lan->sub) : 0);
-	buf = prep_nid_for_label(nid);
-	nlen = strlen(buf) + strlen(lanbuf);
-	nlen += strlen(base) + 4; /* three time '_' and '\0' */
-	ret = xmalloc(nlen);
-	strcpy(ret, "_");
-	strcat(ret, base);
-	strcat(ret, "_");
-	strcat(ret, buf);
-	strcat(ret, "_");
-	strcat(ret, lanbuf);
-	return ret;
+	char *buf = prep_nid_for_label(nid);
+	return strmake( "_%s_%s_%d", base, buf, lan ? MAKELANGID(lan->id, lan->sub) : 0);
 }
 
 /*
diff --git a/tools/wrc/utils.c b/tools/wrc/utils.c
index c9445b3a070..5adebbadebe 100644
--- a/tools/wrc/utils.c
+++ b/tools/wrc/utils.c
@@ -192,6 +192,25 @@ void *xrealloc(void *p, size_t size)
     return res;
 }
 
+char *strmake( const char* fmt, ... )
+{
+    int n;
+    size_t size = 100;
+    va_list ap;
+
+    for (;;)
+    {
+        char *p = xmalloc( size );
+        va_start( ap, fmt );
+        n = vsnprintf( p, size, fmt, ap );
+        va_end( ap );
+        if (n == -1) size *= 2;
+        else if ((size_t)n >= size) size = n + 1;
+        else return p;
+        free( p );
+    }
+}
+
 char *xstrdup(const char *str)
 {
 	char *s;
diff --git a/tools/wrc/utils.h b/tools/wrc/utils.h
index ced55abc3af..19daa09b3a9 100644
--- a/tools/wrc/utils.h
+++ b/tools/wrc/utils.h
@@ -33,6 +33,7 @@ char *xstrdup(const char *str);
 #define __attribute__(X)
 #endif
 
+char *strmake(const char* fmt, ...) __attribute__((__format__ (__printf__, 1, 2 )));
 int parser_error(const char *s, ...) __attribute__((format (printf, 1, 2)));
 int parser_warning(const char *s, ...) __attribute__((format (printf, 1, 2)));
 void internal_error(const char *file, int line, const char *s, ...) __attribute__((format (printf, 3, 4), noreturn));
diff --git a/tools/wrc/wrc.c b/tools/wrc/wrc.c
index 99285dbc991..bbeba8333fd 100644
--- a/tools/wrc/wrc.c
+++ b/tools/wrc/wrc.c
@@ -270,12 +270,7 @@ static int load_file( const char *input_name, const char *output_name )
             exit(0);
         }
 
-        if (output_name && output_name[0])
-        {
-            name = xmalloc( strlen(output_name) + 8 );
-            strcpy( name, output_name );
-            strcat( name, ".XXXXXX" );
-        }
+        if (output_name && output_name[0]) name = strmake( "%s.XXXXXX", output_name );
         else name = xstrdup( "wrc.XXXXXX" );
 
         if ((fd = mkstemps( name, 0 )) == -1)