File perl-recontextnocurpm.diff of Package perl.6851

--- ./regcomp.c.orig	2016-08-03 15:04:42.480044213 +0000
+++ ./regcomp.c	2016-08-03 15:09:57.220043656 +0000
@@ -15456,6 +15456,8 @@ void
 Perl_save_re_context(pTHX)
 {
     dVAR;
+    I32 nparens = -1;
+    I32 i;
 
     struct re_save_state *state;
 
@@ -15483,9 +15485,20 @@ Perl_save_re_context(pTHX)
     /* Save $1..$n (#18107: UTF-8 s/(\w+)/uc($1)/e); AMS 20021106. */
     if (PL_curpm) {
 	const REGEXP * const rx = PM_GETRE(PL_curpm);
-	if (rx) {
-	    U32 i;
-	    for (i = 1; i <= RX_NPARENS(rx); i++) {
+	if (rx)
+            nparens = RX_NPARENS(rx);
+    }
+
+    /* RT #124109. This is a complete hack; in the SWASHNEW case we know
+     * that PL_curpm will be null, but that utf8.pm and the modules it
+     * loads will only use $1..$3.
+     */
+    if (nparens == -1)
+        nparens = 3;
+
+    {
+	{
+	    for (i = 1; i <= nparens; i++) {
 		char digits[TYPE_CHARS(long)];
 		const STRLEN len = my_snprintf(digits, sizeof(digits), "%lu", (long)i);
 		GV *const *const gvp