Fix push parsing memory leak reported by Brandon Lucia at

<http://lists.gnu.org/archive/html/bug-bison/2007-07/msg00032.html>.
* THANKS: Add Brandon Lucia.
* data/push.c (yypstate_delete): Free the stack if it was reallocated
but the parse never completed and thus freed it.
* tests/Makefile.am (TESTSUITE_AT): Add push.at.
* tests/testsuite.at: Include push.at.
* test/push.at: New.
(Push Parsing: Memory Leak for Early Deletion): New test case.

ChangeLog

@@ -1,3 +1,15 @@
+2007-07-27  Joel E. Denny  <jdenny@ces.clemson.edu>
+
+	Fix push parsing memory leak reported by Brandon Lucia at
+	<http://lists.gnu.org/archive/html/bug-bison/2007-07/msg00032.html>.
+	* THANKS: Add Brandon Lucia.
+	* data/push.c (yypstate_delete): Free the stack if it was reallocated
+	but the parse never completed and thus freed it.
+	* tests/Makefile.am (TESTSUITE_AT): Add push.at.
+	* tests/testsuite.at: Include push.at.
+	* test/push.at: New.
+	(Push Parsing: Memory Leak for Early Deletion): New test case.
+
 2007-07-17  Joel E. Denny  <jdenny@ces.clemson.edu>
 
 	Improve handling of multiple S/R conflicts in the same state and of S/R

THANKS

@@ -15,6 +15,7 @@ Baron Schwartz            baron@sequent.org
 Benoit Perrot             benoit.perrot@epita.fr
 Bert Deknuydt             Bert.Deknuydt@esat.kuleuven.ac.be
 Bob Rossi                 bob@brasko.net
+Brandon Lucia             blucia@gmail.com
 Bruce Lilly               blilly@erols.com
 Bruno Haible              bruno@clisp.org
 Charles-Henri de Boysson  de-boy_c@epita.fr

data/push.c

@@ -1124,6 +1124,12 @@ b4_push_if(
 ]b4_c_function_def([[yypstate_delete]], [[void]],
                    [[[yypstate *yyps]], [[yyps]]])[
 {
+#ifndef yyoverflow
+  /* If the stack was reallocated but the parse did not complete, then the
+     stack still needs to be freed.  */
+  if (!yyps->yynew && yyps->yyss != yyps->yyssa)
+    YYSTACK_FREE (yyps->yyss);
+#endif
   free (yyps);
 }
 

tests/Makefile.am

@@ -53,7 +53,8 @@ TESTSUITE_AT = \
         torture.at existing.at regression.at \
         c++.at \
         java.at \
-	cxx-type.at glr-regression.at
+	cxx-type.at glr-regression.at \
+	push.at
 
 TESTSUITE = $(srcdir)/testsuite
 

tests/push.at

@@ -0,0 +1,82 @@
+# Checking Push Parsing.                            -*- Autotest -*-
+# Copyright (C) 2007 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2, or (at your option)
+# any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+# 02110-1301, USA.
+
+AT_BANNER([[Push Parsing Tests]])
+
+## ---------------------------------------------- ##
+## Push Parsing: Memory Leak for Early Deletion.  ##
+## ---------------------------------------------- ##
+
+AT_SETUP([[Push Parsing: Memory Leak for Early Deletion]])
+
+# Requires Valgrind.
+
+AT_DATA_GRAMMAR([[input.y]],
+[[
+%{
+  #include <assert.h>
+  #include <stdio.h>
+  #define YYINITDEPTH 1
+  void yyerror (char const *msg);
+%}
+
+%pure-parser %push-parser
+
+%%
+
+start: 'a' 'b' 'c' ;
+
+%%
+
+void
+yyerror (char const *msg)
+{
+  fprintf (stderr, "%s\n", msg);
+}
+
+int
+main (void)
+{
+  yypstate *yyps;
+  YYSTYPE yylval;
+
+  /* Make sure we don't try to free yyps->yyss in this case.  */
+  yyps = yypstate_new ();
+  yypstate_delete (yyps);
+
+  /* yypstate_delete used to leak yyps->yyss if the stack was reallocated but
+     the parse did not return on success, syntax error, or memory
+     exhaustion.  */
+  yyps = yypstate_new ();
+  assert (yypush_parse (yyps, 'a', &yylval) == YYPUSH_MORE);
+  yypstate_delete (yyps);
+
+  yyps = yypstate_new ();
+  assert (yypush_parse (yyps, 'a', &yylval) == YYPUSH_MORE);
+  assert (yypush_parse (yyps, 'b', &yylval) == YYPUSH_MORE);
+  yypstate_delete (yyps);
+
+  return 0;
+}
+]])
+
+AT_CHECK([[bison -o input.c input.y]])
+AT_COMPILE([[input]])
+AT_PARSER_CHECK([[./input]])
+
+AT_CLEANUP

tests/testsuite.at

@@ -80,5 +80,8 @@ m4_include([cxx-type.at])
 # Regression tests
 m4_include([glr-regression.at])
 
+# Push parsing specific tests.
+m4_include([push.at])
+
 m4_popdef([AT_CHECK])
 m4_popdef([ORIGINAL_AT_CHECK])