# HG changeset patch
# User Bram Moolenaar <Bram@vim.org>
# Date 1645270204 -3600
# Node ID bfce04a9956103e6cf4ca933aaee699041a0d88c
# Parent  59ce43efd4bea1b2ad7bd2d3d38b7c1ee15808bb
patch 8.2.4418: crash when using special multi-byte character

Commit: https://github.com/vim/vim/commit/5921aeb5741fc6e84c870d68c7c35b93ad0c9f87
Author: Bram Moolenaar <Bram@vim.org>
Date:   Sat Feb 19 11:20:12 2022 +0000

    patch 8.2.4418: crash when using special multi-byte character

    Problem:    Crash when using special multi-byte character.
    Solution:   Don't use isalpha() for an arbitrary character.

diff --git a/src/charset.c b/src/charset.c
--- a/src/charset.c
+++ b/src/charset.c
@@ -1645,6 +1645,12 @@ vim_isupper(int c)
 }
 
     int
+vim_isalpha(int c)
+{
+    return vim_islower(c) || vim_isupper(c);
+}
+
+    int
 vim_toupper(int c)
 {
     if (c <= '@')
diff --git a/src/filepath.c b/src/filepath.c
--- a/src/filepath.c
+++ b/src/filepath.c
@@ -3626,7 +3626,7 @@ unix_expandpath(
 	else if (path_end >= path + wildoff
 			 && (vim_strchr((char_u *)"*?[{~$", *path_end) != NULL
 			     || (!p_fic && (flags & EW_ICASE)
-					     && isalpha(PTR2CHAR(path_end)))))
+					  && vim_isalpha(PTR2CHAR(path_end)))))
 	    e = p;
 	if (has_mbyte)
 	{
diff --git a/src/proto/charset.pro b/src/proto/charset.pro
--- a/src/proto/charset.pro
+++ b/src/proto/charset.pro
@@ -50,6 +50,7 @@ int vim_isxdigit(int c);
 int vim_isbdigit(int c);
 int vim_islower(int c);
 int vim_isupper(int c);
+int vim_isalpha(int c);
 int vim_toupper(int c);
 int vim_tolower(int c);
 char_u *skiptowhite(char_u *p);
@@ -63,5 +64,4 @@ int hexhex2nr(char_u *p);
 int rem_backslash(char_u *str);
 void backslash_halve(char_u *p);
 char_u *backslash_halve_save(char_u *p);
-void ebcdic2ascii(char_u *buffer, int len);
 /* vim: set ft=c : */
diff --git a/src/testdir/test_autochdir.vim b/src/testdir/test_autochdir.vim
--- a/src/testdir/test_autochdir.vim
+++ b/src/testdir/test_autochdir.vim
@@ -110,4 +110,12 @@ func Test_verbose_pwd()
   call delete('Xautodir', 'rf')
 endfunc
 
+func Test_multibyte()
+  " using an invalid character should not cause a crash
+  set wic
+  call assert_fails('tc �����*', 'E344:')
+  set nowic
+endfunc
+
+
 " vim: shiftwidth=2 sts=2 expandtab
diff --git a/src/version.c b/src/version.c
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    4418,
+/**/
     4417,
 /**/
     4416,