From: Nicholas Clark <nick@ccl4.org>
Date: Mon, 17 Nov 2008 22:31:07 +0000 (+0000)
Subject: No need to str*cpy() a string of known fixed length ("_<(eval )") when
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=e389bba906c384f4fc3f3ad5e721e737cbd5d54e;p=p5sagit%2Fp5-mst-13.2.git

No need to str*cpy() a string of known fixed length ("_<(eval )") when
a simple 1 byte write has the same desired effect.
Clearly the Campaign for the Elimination of strlen() needs to branch
out into str*cat() and str*cpy().

p4raw-id: //depot/perl@34874
---

diff --git a/pp_ctl.c b/pp_ctl.c
index b2cbbde..cd5c1c1 100644
--- a/pp_ctl.c
+++ b/pp_ctl.c
@@ -3662,9 +3662,7 @@ PP(pp_entereval)
     CV* runcv;
     U32 seq;
     HV *saved_hh = NULL;
-    const char * const fakestr = "_<(eval )";
-    const int fakelen = 9 + 1;
-    
+
     if (PL_op->op_private & OPpEVAL_HAS_HH) {
 	saved_hh = MUTABLE_HV(SvREFCNT_inc(POPs));
     }
@@ -3735,8 +3733,13 @@ PP(pp_entereval)
     if ((PERLDB_LINE || PERLDB_SAVESRC)
 	&& was != (I32)PL_sub_generation /* Some subs defined here. */
 	&& ok) {
-	/* Copy in anything fake and short. */
-	my_strlcpy(safestr, fakestr, fakelen);
+	/* Just need to change the string in our writable scratch buffer that
+	   will be used at scope exit to delete this eval's "file" name, to
+	   something safe. The key names are of the form "_<(eval 1)" upwards,
+	   so the 8th char is the first digit, which will not have a leading
+	   zero. So give it a leading zero, and it can't match anything, but
+	   still sits within the pattern space "reserved" for evals.  */
+	safestr[8] = '0';
     }
     return ok ? DOCATCH(PL_eval_start) : PL_op->op_next;
 }