From 566a4373528224e69d78518db4305047a2cbe53f Mon Sep 17 00:00:00 2001
From: Nicholas Clark <nick@ccl4.org>
Date: Thu, 18 Feb 2010 15:38:11 +0000
Subject: [PATCH] Avoid a panic from the UTF-8 length cache if the length
 overflows 32 bits.

Rather than storing a value, and having it wrap to a wrong value, treat such
lengths as "still unknown". This is a work around until a proper solution is
designed an implemented.
---
 sv.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/sv.c b/sv.c
index 40c95d5..53e3410 100644
--- a/sv.c
+++ b/sv.c
@@ -6072,6 +6072,10 @@ Perl_sv_len_utf8(pTHX_ register SV *const sv)
 		    }
 		    assert(mg);
 		    mg->mg_len = ulen;
+		    /* For now, treat "overflowed" as "still unknown".
+		       See RT #72924.  */
+		    if (ulen != (STRLEN) mg->mg_len)
+			mg->mg_len = -1;
 		}
 	    }
 	    return ulen;
-- 
2.7.4