1 files changed, 10 insertions, 4 deletions

diff --git a/src/regex.c b/src/regex.c
index dd3f2b3cd67..164eb4612ae 100644
--- a/src/regex.c
+++ b/src/regex.c
@@ -5444,7 +5444,7 @@ re_match_2_internal (struct re_pattern_buffer *bufp, const_re_char *string1,
         case charset:
         case charset_not:
           {
-            register unsigned int c;
+            register unsigned int c, corig;
             boolean not = (re_opcode_t) *(p - 1) == charset_not;
             int len;
 
@@ -5473,7 +5473,7 @@ re_match_2_internal (struct re_pattern_buffer *bufp, const_re_char *string1,
               }
 
             PREFETCH ();
-            c = RE_STRING_CHAR_AND_LENGTH (d, len, target_multibyte);
+            corig = c = RE_STRING_CHAR_AND_LENGTH (d, len, target_multibyte);
             if (target_multibyte)
               {
                 int c1;
@@ -5517,11 +5517,17 @@ re_match_2_internal (struct re_pattern_buffer *bufp, const_re_char *string1,
               {
                 int class_bits = CHARSET_RANGE_TABLE_BITS (&p[-1]);
 
-                if (  (class_bits & BIT_LOWER && ISLOWER (c))
+                if (  (class_bits & BIT_LOWER
+                       && (ISLOWER (c)
+                           || (corig != c
+                               && c == upcase (corig) && ISUPPER(c))))
                     | (class_bits & BIT_MULTIBYTE)
                     | (class_bits & BIT_PUNCT && ISPUNCT (c))
                     | (class_bits & BIT_SPACE && ISSPACE (c))
-                    | (class_bits & BIT_UPPER && ISUPPER (c))
+                    | (class_bits & BIT_UPPER
+                       && (ISUPPER (c)
+                           || (corig != c
+                               && c == downcase (corig) && ISLOWER (c))))
                     | (class_bits & BIT_WORD  && ISWORD  (c))
                     | (class_bits & BIT_ALPHA && ISALPHA (c))
                     | (class_bits & BIT_ALNUM && ISALNUM (c))