From: Jan Dubois <jand@activestate.com>
Date: Mon, 16 Nov 2009 22:43:20 +0000 (-0800)
Subject: Fix crash in refactored lexer internals
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=490354310ada83dc35c6cfd9dd59ad62781fcaf7;p=p5sagit%2Fp5-mst-13.2.git

Fix crash in refactored lexer internals

Commit f0e67a1d29102aa9905aecf2b0f98449697d5af3 changed the control
flow so that PerlIO_tell(PL_rsfp) could be called when PL_rsfp was
NULL, which produces a crash at least on Windows with the MSVCRT
runtime.

This change moves the detection if PL_rsfp is NULL or not closer to
the location where is is actually tested, which gets rid of the
crashes.  I however have *not* verified if the changes in control
flow in f0e67a1d are otherwise correct or not.
---

diff --git a/toke.c b/toke.c
index 6793f7b..6b5ef4f 100644
--- a/toke.c
+++ b/toke.c
@@ -4315,7 +4315,6 @@ Perl_yylex(pTHX)
 	}
 	do {
 	    U32 fake_eof = 0;
-	    bof = PL_rsfp ? TRUE : FALSE;
 	    if (0) {
 	      fake_eof:
 		fake_eof = LEX_FAKE_EOF;
@@ -4332,6 +4331,7 @@ Perl_yylex(pTHX)
 	    s = PL_bufptr;
 	    /* If it looks like the start of a BOM or raw UTF-16,
 	     * check if it in fact is. */
+	    bof = PL_rsfp ? TRUE : FALSE;
 	    if (bof &&
 		     (*s == 0 ||
 		      *(U8*)s == 0xEF ||