Silly Nick. There was a bug in change 30757 whereby the precomp of a

dup'd regexp would be pointing somewhere la-la. Probably at the precomp
of the same regexp in the parent thread. (So it is only likely to go
nasal daemon if the parent thread terminates first, or explicitly goes
around freeing up run time generated regexps.)

p4raw-id: //depot/perl@32754

1 files changed, 4 insertions, 1 deletions

diff --git a/regcomp.c b/regcomp.c
index 9732086110..544bbbc9d0 100644
--- a/regcomp.c
+++ b/regcomp.c
@@ -9371,6 +9371,7 @@ Perl_re_dup(pTHX_ const regexp *r, CLONE_PARAMS *param)
     dVAR;
     regexp *ret;
     I32 npar;
+    U32 precomp_offset;
 
     if (!r)
 	return (REGEXP *)NULL;
@@ -9419,8 +9420,10 @@ Perl_re_dup(pTHX_ const regexp *r, CLONE_PARAMS *param)
 	}
     }
 
+    precomp_offset = RX_PRECOMP(ret) - ret->wrapped;
+
     ret->wrapped        = SAVEPVN(ret->wrapped, ret->wraplen+1);
-    RX_PRECOMP(ret)        = ret->wrapped + (RX_PRECOMP(ret) - ret->wrapped);
+    RX_PRECOMP(ret)     = ret->wrapped + precomp_offset;
     ret->paren_names    = hv_dup_inc(ret->paren_names, param);
 
     if (ret->pprivate)