[perl #119169] index with __PACKAGE__ for 2nd argument

The refactoring of fbm_compile in 66379c06cd to prepare for
c72a4eedff1 put in an SvIsCOW check before doing SvPV_force.  I sim-
ply changed the logic there so that SvPV_force would continue to have
its effect but without tripping up on read-only variables for which
SvPV_force would not need to make any changes anyway.

Now, if a COW scalar is read-only, we can’t call SvPV_force on it,
because it will die.

It turns out that we don’t actually need to call SvPV_force on COWs.
We can just go ahead and attach the BM magic and continue sharing
the buffer.

1 files changed, 1 insertions, 1 deletions

diff --git a/util.c b/util.c
index be75796eda..316f45d5fe 100644
--- a/util.c
+++ b/util.c
@@ -539,7 +539,7 @@ Perl_fbm_compile(pTHX_ SV *sv, U32 flags)
 	if (mg && mg->mg_len >= 0)
 	    mg->mg_len++;
     }
-    if (!SvPOK(sv) || SvNIOKp(sv) || SvIsCOW(sv))
+    if (!SvPOK(sv) || SvNIOKp(sv))
 	s = (U8*)SvPV_force_mutable(sv, len);
     else s = (U8 *)SvPV_mutable(sv, len);
     if (len == 0)		/* TAIL might be on a zero-length string. */