diff --git a/src/proto/misc2.pro b/src/proto/misc2.pro
index 44f22f2..3477452 100644
--- a/src/proto/misc2.pro
+++ b/src/proto/misc2.pro
@@ -32,14 +32,14 @@
 void do_outofmem_msg(size_t size);
 void free_all_mem(void);
 char_u *vim_strsave(char_u *string);
-char_u *vim_strnsave(char_u *string, int len);
+char_u *vim_strnsave(char_u *string, size_t len);
 char_u *vim_memsave(char_u *p, size_t len);
 char_u *vim_strsave_escaped(char_u *string, char_u *esc_chars);
 char_u *vim_strsave_escaped_ext(char_u *string, char_u *esc_chars, int cc, int bsl);
 int csh_like_shell(void);
 char_u *vim_strsave_shellescape(char_u *string, int do_special, int do_newline);
 char_u *vim_strsave_up(char_u *string);
-char_u *vim_strnsave_up(char_u *string, int len);
+char_u *vim_strnsave_up(char_u *string, size_t len);
 void vim_strup(char_u *p);
 char_u *strup_save(char_u *orig);
 char_u *strlow_save(char_u *orig);