(?foo:...) loses passed in charset

This commit looks for the passed-in charset, and overrides it only if it
is /d and the pattern requires /u.  Previously the passed-in value was
ignored.

Author: Karl Williamson

regcomp.c

@@ -8010,9 +8010,12 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
                 U32 posflags = 0, negflags = 0;
 	        U32 *flagsp = &posflags;
                 char has_charset_modifier = '\0';
-		regex_charset cs = (RExC_utf8 || RExC_uni_semantics)
-				    ? REGEX_UNICODE_CHARSET
-				    : REGEX_DEPENDS_CHARSET;
+		regex_charset cs = get_regex_charset(RExC_flags);
+		if (cs == REGEX_DEPENDS_CHARSET
+		    && (RExC_utf8 || RExC_uni_semantics))
+		{
+		    cs = REGEX_UNICODE_CHARSET;
+		}
 
 		while (*RExC_parse) {
 		    /* && strchr("iogcmsx", *RExC_parse) */

t/re/pat.t

@@ -21,7 +21,7 @@ BEGIN {
     require './test.pl';
 }
 
-plan tests => 469;  # Update this when adding/deleting tests.
+plan tests => 472;  # Update this when adding/deleting tests.
 
 run_tests() unless caller;
 
@@ -1253,6 +1253,15 @@ EOP
         $anch_count++ while $str=~/^.*/mg;
         is $anch_count, 1, 'while "\n"=~/^.*/mg should match only once';
     }
+
+    { # [perl #111174]
+        use re '/u';
+        like "\xe0", qr/(?i:\xc0)/, "(?i: shouldn't lose the passed in /u";
+        use re '/a';
+        unlike "\x{100}", qr/(?i:\w)/, "(?i: shouldn't lose the passed in /a";
+        use re '/aa';
+        unlike 'k', qr/(?i:\N{KELVIN SIGN})/, "(?i: shouldn't lose the passed in /aa";
+    }
 } # End of sub run_tests
 
 1;