[BZ 697]

* posix/regexec.c (prune_impossible_nodes): Handle sifted_states[0]
	being NULL also if there are no backreferences.
	* posix/rxspencer/tests: Add testcases.

ChangeLog

@@ -1,3 +1,10 @@
+2009-01-05  Paolo Bonzini  <bonzini@gnu.org>
+
+	[BZ 697]
+	* posix/regexec.c (prune_impossible_nodes): Handle sifted_states[0]
+	being NULL also if there are no backreferences.
+	* posix/rxspencer/tests: Add testcases.
+
 2009-01-04  Paolo Bonzini  <bonzini@gnu.org>
 
 	[BZ 9697]

posix/regexec.c

@@ -1,5 +1,5 @@
 /* Extended regular expression matching and search library.
-   Copyright (C) 2002, 2003, 2004, 2005, 2007 Free Software Foundation, Inc.
+   Copyright (C) 2002, 2003, 2004, 2005, 2007, 2009 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Isamu Hasegawa <isamu@yamato.ibm.com>.
 
@@ -1004,6 +1004,11 @@ prune_impossible_nodes (mctx)
       re_node_set_free (&sctx.limits);
       if (BE (ret != REG_NOERROR, 0))
 	goto free_return;
+      if (sifted_states[0] == NULL)
+	{
+	  ret = REG_NOMATCH;
+	  goto free_return;
+	}
     }
   re_free (mctx->state_log);
   mctx->state_log = sifted_states;

posix/rxspencer/tests

@@ -536,3 +536,7 @@ a.*\b	&	abT	ab
 \B	&	aSbTc
 \B	&	SaT	@SaT
 \B	&	aSTSb	@TSb
+
+o$($|.)	-	oN
+o$($|.)	-	op
+o$($|.)	-	o	o