PATCH: [perl #133899] panic in s///

Thanks for finding this bug, and the others you've been finding.

A new regnode was added, but this function was not updated to account
for that.  I've now checked all the other new regnodes in 5.29 and this
was the only missing one.

Author: khwilliamson

regexec.c

@@ -4548,6 +4548,9 @@ S_setup_EXACTISH_ST_c1_c2(pTHX_ const regnode * const text_node, int *c1p,
                     case EXACTFU:
                         c2 = PL_fold_latin1[c1];
                         break;
+                    case EXACTFU_ONLY8:
+                        return FALSE;
+                        NOT_REACHED; /* NOTREACHED */
 
                     default:
                         Perl_croak(aTHX_ "panic: Unexpected op %u", OP(text_node));

t/re/subst.t

@@ -11,7 +11,7 @@ BEGIN {
     require './loc_tools.pl';
 }
 
-plan(tests => 276);
+plan(tests => 277);
 
 $_ = 'david';
 $a = s/david/rules/r;
@@ -1174,5 +1174,8 @@ __EOF__
     is $lines, 4, "RT #131930";
 }
 
+{   # [perl $133899], would panic
 
-
+    fresh_perl_is('my $a = "ha"; $a =~ s!|0?h\x{300}(?{})!!gi', "", {},
+                  "[perl #133899] s!|0?h\\x{300}(?{})!!gi panics");
+}