From 30382c73ff93b57b951492a5a0d1cba2de577e49 Mon Sep 17 00:00:00 2001
From: Ilya Zakharevich <ilya@math.berkeley.edu>
Date: Mon, 4 Oct 1999 15:58:03 -0400
Subject: [PATCH] Re: Strange RE engine breakage in 5_61
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To: François Désarménien <desar@club-internet.fr>
Cc: "perl5-porters@perl.org" <perl5-porters@perl.org>
Message-ID: <19991004195803.A21760@monk.mps.ohio-state.edu>

(had to apply pat.t part manually because there
 already were more tests than there was in _61)

p4raw-id: //depot/cfgperl@4301
---
 regcomp.c     |  4 +++-
 regexec.c     | 22 +++++++++++++---------
 t/op/pat.t    |  8 +++++++-
 t/op/re_tests |  1 +
 4 files changed, 24 insertions(+), 11 deletions(-)

diff --git a/regcomp.c b/regcomp.c
index 921472a..99423e1 100644
--- a/regcomp.c
+++ b/regcomp.c
@@ -1076,7 +1076,9 @@ Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
 	    r->check_offset_min = data.offset_float_min;
 	    r->check_offset_max = data.offset_float_max;
 	}
-	if (r->check_substr) {
+	/* XXXX Currently intuiting is not compatible with ANCH_GPOS.
+	   This should be changed ASAP!  */
+	if (r->check_substr && !(r->reganch & ROPT_ANCH_GPOS)) {
 	    r->reganch |= RE_USE_INTUIT;
 	    if (SvTAIL(r->check_substr))
 		r->reganch |= RE_INTUIT_TAIL;
diff --git a/regexec.c b/regexec.c
index a567353..048ae49 100644
--- a/regexec.c
+++ b/regexec.c
@@ -739,19 +739,23 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
     /* If there is a "must appear" string, look for it. */
     s = startpos;
 
-    if (prog->reganch & ROPT_GPOS_SEEN) {
+    if (prog->reganch & ROPT_GPOS_SEEN) { /* Need to have PL_reg_ganch */
 	MAGIC *mg;
 
-	if (!(flags & REXEC_IGNOREPOS) && sv && SvTYPE(sv) >= SVt_PVMG
-	    && SvMAGIC(sv) && (mg = mg_find(sv, 'g')) && mg->mg_len >= 0)
-	    PL_reg_ganch = strbeg + mg->mg_len;
-	else
+	if (flags & REXEC_IGNOREPOS)	/* Means: check only at start */
 	    PL_reg_ganch = startpos;
-	if (prog->reganch & ROPT_ANCH_GPOS) {
-	    if (s > PL_reg_ganch)
-		goto phooey;
-	    s = PL_reg_ganch;
+	else if (sv && SvTYPE(sv) >= SVt_PVMG
+		  && SvMAGIC(sv)
+		  && (mg = mg_find(sv, 'g')) && mg->mg_len >= 0) {
+	    PL_reg_ganch = strbeg + mg->mg_len;	/* Defined pos() */
+	    if (prog->reganch & ROPT_ANCH_GPOS) {
+		if (s > PL_reg_ganch)
+		    goto phooey;
+		s = PL_reg_ganch;
+	    }
 	}
+	else				/* pos() not defined */
+	    PL_reg_ganch = strbeg;
     }
 
     if (!(flags & REXEC_CHECKED) && prog->check_substr != Nullsv) {
diff --git a/t/op/pat.t b/t/op/pat.t
index 89cc2bb..f36394e 100755
--- a/t/op/pat.t
+++ b/t/op/pat.t
@@ -4,7 +4,7 @@
 # the format supported by op/regexp.t.  If you want to add a test
 # that does fit that format, add it to op/re_tests, not here.
 
-print "1..192\n";
+print "1..193\n";
 
 BEGIN {
     chdir 't' if -d 't';
@@ -887,3 +887,9 @@ pos=1;
 m/^-.*bb/mg and print "not ";
 print "ok $test\n";
 $test++;
+
+$text = "aaXbXcc";
+pos($text)=0;
+$text =~ /\GXb*X/g and print 'not ';
+print "ok $test\n";
+$test++;
diff --git a/t/op/re_tests b/t/op/re_tests
index b35e964..695672d 100644
--- a/t/op/re_tests
+++ b/t/op/re_tests
@@ -739,3 +739,4 @@ tt+$	xxxtt	y	-	-
 [\w-z]	-	c	-	/[\w-z]/: invalid [] range in regexp
 [0-[:digit:]]	-	c	-	/[0-[:digit:]]/: invalid [] range in regexp
 [[:digit:]-9]	-	c	-	/[[:digit:]-9]/: invalid [] range in regexp
+\GX.*X	aaaXbX	n	-	-
-- 
2.7.4