# Bison Regressions. -*- Autotest -*-
-# Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software
-# Foundation, Inc.
+# Copyright (C) 2001-2012 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
AT_SETUP([Trivial grammars])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([input.y],
[[%{
-void yyerror (char const *);
-int yylex (void);
+]AT_YYERROR_DECLARE_EXTERN[
+]AT_YYLEX_DECLARE_EXTERN[
#define YYSTYPE int *
%}
program: 'x';
]])
+AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([-o input.c input.y])
AT_COMPILE([input.o], [-c input.c])
AT_SETUP([YYSTYPE typedef])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([input.y],
[[%{
-void yyerror (char const *);
-int yylex (void);
+]AT_YYERROR_DECLARE_EXTERN[
+]AT_YYLEX_DECLARE_EXTERN[
typedef union { char const *val; } YYSTYPE;
%}
program: { $$ = ""; };
]])
+AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([-o input.c input.y])
AT_COMPILE([input.o], [-c input.c])
# Found in GCJ: they expect the tokens to be defined before the user
# prologue, so that they can use the token definitions in it.
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([input.y],
[[%{
-void yyerror (const char *s);
-int yylex (void);
+]AT_YYERROR_DECLARE_EXTERN[
+]AT_YYLEX_DECLARE_EXTERN[
%}
%union
exp: MY_TOKEN;
%%
]])
+AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([-y -o input.c input.y])
AT_COMPILE([input.o], [-c input.c])
# Found in GCJ: they expect the tokens to be defined before the user
# prologue, so that they can use the token definitions in it.
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([input.y],
[[%{
#include <stdio.h>
-void yyerror (const char *s);
-int yylex (void);
+]AT_YYERROR_DECLARE_EXTERN[
+]AT_YYLEX_DECLARE_EXTERN[
void print_my_token (void);
%}
exp: MY_TOKEN;
%%
]])
+AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([-o input.c input.y])
AT_COMPILE([input.o], [-c input.c])
AT_SETUP([Braces parsing])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA([input.y],
-[[/* Bison used to swallow the character after `}'. */
+[[/* Bison used to swallow the character after '}'. */
%%
exp: { tests = {{{{{{{{{{}}}}}}}}}}; };
%%
]])
+AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([-v -o input.c input.y])
AT_SETUP([Duplicate string])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA([input.y],
-[[/* `Bison -v' used to dump core when two tokens are defined with the same
+[[/* 'Bison -v' used to dump core when two tokens are defined with the same
string, as LE and GE below. */
%token NUM
exp: '(' exp ')' | NUM ;
%%
]])
+AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([-v -o input.c input.y], 0, [],
-[[input.y:6.8-14: warning: symbol `"<="' used more than once as a literal string
+[[input.y:6.8-14: warning: symbol "<=" used more than once as a literal string
]])
AT_CLEANUP
AT_KEYWORDS([report])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA([input.y],
[[%%
expr:
};
]])
+AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([-o input.c -v input.y])
]])
AT_BISON_CHECK([input.y], [1], [],
-[[input.y:2.1: invalid character: `?'
-input.y:3.14: invalid character: `}'
-input.y:4.1: invalid character: `%'
-input.y:4.2: invalid character: `&'
-input.y:5.1-17: invalid directive: `%a-does-not-exist'
-input.y:6.1: invalid character: `%'
-input.y:6.2: invalid character: `-'
-input.y:7.1-8.0: missing `%}' at end of file
+[[input.y:2.1: invalid character: '?'
+input.y:3.14: invalid character: '}'
+input.y:4.1: invalid character: '%'
+input.y:4.2: invalid character: '&'
+input.y:5.1-17: invalid directive: '%a-does-not-exist'
+input.y:6.1: invalid character: '%'
+input.y:6.2: invalid character: '-'
+input.y:7.1-8.0: missing '%}' at end of file
input.y:7.1-8.0: syntax error, unexpected %{...%}
]])
AT_SETUP([Token definitions])
-# Bison managed, when fed with `%token 'f' "f"' to #define 'f'!
+AT_BISON_OPTION_PUSHDEFS
+# Bison managed, when fed with '%token 'f' "f"' to #define 'f'!
AT_DATA_GRAMMAR([input.y],
[%{
#include <stdlib.h>
#include <stdio.h>
-void yyerror (const char *s);
-int yylex (void);
+]AT_YYERROR_DECLARE[
+]AT_YYLEX_DECLARE[
%}
[%error-verbose
%token MYEOF 0 "end of file"
%token C_TOKEN 'c'
%token 'd' D_TOKEN
%token SPECIAL "\\\'\?\"\a\b\f\n\r\t\v\001\201\x001\x000081??!"
+%token SPECIAL "\\\'\?\"\a\b\f\n\r\t\v\001\201\x001\x000081??!"
%%
exp: "a" "\\\'\?\"\a\b\f\n\r\t\v\001\201\x001\x000081??!";
%%
return yyparse ();
}
]])
+AT_BISON_OPTION_POPDEFS
-AT_BISON_CHECK([-o input.c input.y])
+# Checking the warning message guarantees that the trigraph "??!" isn't
+# unnecessarily escaped here even though it would need to be if encoded in a
+# C-string literal. Also notice that unnecessary escaping, such as "\?", from
+# the user specification is eliminated.
+AT_BISON_CHECK([-o input.c input.y], [[0]], [[]],
+[[input.y:22.8-14: warning: symbol SPECIAL redeclared
+input.y:22.8-63: warning: symbol "\\'?\"\a\b\f\n\r\t\v\001\201\001\201??!" used more than once as a literal string
+]])
AT_COMPILE([input])
+
+# Checking the error message here guarantees that yytname, which does contain
+# C-string literals, does have the trigraph escaped correctly. Thus, the
+# symbol name reported by the parser is exactly the same as that reported by
+# Bison itself.
AT_DATA([experr],
-[[syntax error, unexpected "\\'?\"\a\b\f\n\r\t\v\001\201\001\201?\?!", expecting a
+[[syntax error, unexpected "\\'?\"\a\b\f\n\r\t\v\001\201\001\201??!", expecting a
]])
AT_PARSER_CHECK([./input], 1, [], [experr])
AT_CLEANUP
AT_SETUP([Characters Escapes])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([input.y],
[%{
-void yyerror (const char *s);
-int yylex (void);
+]AT_YYERROR_DECLARE_EXTERN[
+]AT_YYLEX_DECLARE_EXTERN[
%}
[%%
exp:
'\'' "\'"
| '\"' "\""
-| '"' "'"
+| '"' "'" /* Pacify font-lock-mode: ". */
;
]])
-# Pacify font-lock-mode: "
+
+AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([-o input.c input.y])
AT_COMPILE([input.o], [-c input.c])
# The generation of the reduction was once wrong in Bison, and made it
# miss some reductions. In the following test case, the reduction on
-# `undef_id_tok' in state 1 was missing. This is stripped down from
+# 'undef_id_tok' in state 1 was missing. This is stripped down from
# the actual web2c.y.
AT_SETUP([Web2c Report])
## Web2c Actions. ##
## --------------- ##
-# The generation of the mapping `state -> action' was once wrong in
+# The generation of the mapping 'state -> action' was once wrong in
# extremely specific situations. web2c.y exhibits this situation.
# Below is a stripped version of the grammar. It looks like one can
# simplify it further, but just don't: it is tuned to exhibit a bug,
static const char *const yytname[] =
{
"$end", "error", "$undefined", "\"if\"", "\"const\"", "\"then\"",
- "\"else\"", "$accept", "statement", "struct_stat", "if", "else", 0
+ "\"else\"", "$accept", "statement", "struct_stat", "if", "else", YY_NULL
};
static const yytype_uint16 yytoknum[] =
{
AT_LALR1_CC_IF([],
[#include <stdlib.h>
#include <stdio.h>
-static void yyerror (const char *);])
+]AT_YYERROR_DECLARE[])
%}
$1
%token ARROW INVALID NUMBER STRING DATA
AT_BISON_OPTION_PUSHDEFS([$1])
_AT_DATA_DANCER_Y([$1])
AT_BISON_CHECK([-o dancer.c dancer.y])
-AT_LALR1_CC_IF(
- [AT_BISON_CHECK([-o dancer.cc dancer.y])
- AT_COMPILE_CXX([dancer])],
- [AT_BISON_CHECK([-o dancer.c dancer.y])
- AT_COMPILE([dancer])])
+AT_FULL_COMPILE([dancer])
AT_PARSER_CHECK([./dancer], 1, [],
[syntax error, unexpected ':'
])
# --------------------------------
m4_define([_AT_DATA_EXPECT2_Y],
[AT_DATA_GRAMMAR([expect2.y],
-[%{
-static int yylex (AT_LALR1_CC_IF([int *], [void]));
+[[%{
+static int yylex (]AT_LALR1_CC_IF([int *], [void]));
AT_LALR1_CC_IF([],
-[#include <stdio.h>
+[[#include <stdio.h>
#include <stdlib.h>
-static void yyerror (const char *);])
+]AT_YYERROR_DECLARE])[
%}
$1
%defines
t: A | B;
%%
-AT_LALR1_CC_IF(
-[/* A C++ error reporting function. */
-void
-yy::parser::error (const location&, const std::string& m)
-{
- std::cerr << m << std::endl;
-}
-
-int
+]AT_YYERROR_DEFINE[
+]AT_LALR1_CC_IF(
+[int
yyparse ()
{
yy::parser parser;
return parser.parse ();
}
-],
-[static void
-yyerror (const char *s)
-{
- fprintf (stderr, "%s\n", s);
-}])
+])[
static int
-yylex (AT_LALR1_CC_IF([int *lval], [void]))
-[{
+yylex (]AT_LALR1_CC_IF([int *lval], [void])[)
+{
static int const tokens[] =
{
1000, '+', '+', -1
if (! (toknum < sizeof tokens / sizeof *tokens))
abort ();
return tokens[toknum++];
-}]
+}
int
main (void)
{
return yyparse ();
}
-])
+]])
])# _AT_DATA_EXPECT2_Y
# AT_CHECK_EXPECT2(BISON-OPTIONS)
-# ------------------------------
+# -------------------------------
# Generate the grammar, compile it, run it.
m4_define([AT_CHECK_EXPECT2],
[AT_SETUP([Expecting two tokens $1])
AT_BISON_OPTION_PUSHDEFS([$1])
_AT_DATA_EXPECT2_Y([$1])
AT_BISON_CHECK([-o expect2.c expect2.y])
-AT_LALR1_CC_IF(
- [AT_BISON_CHECK([-o expect2.cc expect2.y])
- AT_COMPILE_CXX([expect2])],
- [AT_BISON_CHECK([-o expect2.c expect2.y])
- AT_COMPILE([expect2])])
+AT_FULL_COMPILE([expect2])
AT_PARSER_CHECK([./expect2], 1, [],
[syntax error, unexpected '+', expecting A or B
])
# Bison once mistook braced code in a declaration in the rules section to be a
# rule action.
-
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([input.y],
[[%{
#include <stdio.h>
-static void yyerror (char const *msg);
-static int yylex (void);
+]AT_YYERROR_DECLARE[
+]AT_YYLEX_DECLARE[
%}
%error-verbose
%%
-static void
-yyerror (char const *msg)
-{
- fprintf (stderr, "%s\n", msg);
-}
-
+]AT_YYERROR_DEFINE[
static int
yylex (void)
{
return !yyparse ();
}
]])
+AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([-t -o input.c input.y])
AT_COMPILE([input])
# state's one item that (1) is associated with the same rule as the reduction
# and (2) has its dot at the end of its RHS. Previously, Bison also
# erroneously printed the lookahead set next to all of the state's other items
-# associated with the same rule. This bug affected only the `.output' file and
+# associated with the same rule. This bug affected only the '.output' file and
# not the generated parser source code.
AT_DATA([[input.y]],
]])
AT_CLEANUP
+
+
+
+## ---------------------------------------- ##
+## Token number in precedence declaration. ##
+## ---------------------------------------- ##
+
+AT_SETUP([[Token number in precedence declaration]])
+
+# POSIX says token numbers can be declared in %left, %right, and %nonassoc, but
+# we lost this in Bison 1.50.
+AT_BISON_OPTION_PUSHDEFS
+AT_DATA_GRAMMAR([input.y],
+[[%{
+ #include <stdio.h>
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
+%}
+
+%error-verbose
+%right END 0
+%left TK1 1 TK2 2 "tok alias" 3
+
+%%
+
+start:
+ TK1 sr_conflict "tok alias"
+ | start %prec END
+ ;
+sr_conflict:
+ TK2
+ | TK2 "tok alias"
+ ;
+
+%%
+
+]AT_YYERROR_DEFINE[
+int
+yylex (void)
+{
+ static int const input[] = { 1, 2, 3, 0 };
+ static int const *inputp = input;
+ return *inputp++;
+}
+
+int
+main (void)
+{
+ return yyparse ();
+}
+]])
+AT_BISON_OPTION_POPDEFS
+
+AT_BISON_CHECK([[-o input.c input.y]], [[0]],,
+[[input.y:23.5-19: warning: rule useless in parser due to conflicts: start: start
+input.y:27.5-19: warning: rule useless in parser due to conflicts: sr_conflict: TK2 "tok alias"
+]])
+AT_COMPILE([[input]])
+AT_PARSER_CHECK([[./input]])
+
+AT_CLEANUP
+
+
+
+## --------------------------- ##
+## parse-gram.y: LALR = IELR. ##
+## --------------------------- ##
+
+# If parse-gram.y's LALR and IELR parser tables ever begin to differ, we
+# need to fix parse-gram.y or start using IELR.
+
+AT_SETUP([[parse-gram.y: LALR = IELR]])
+
+# Avoid differences in synclines by telling bison that the output files
+# have the same name.
+[cp $abs_top_srcdir/src/parse-gram.y input.y]
+AT_BISON_CHECK([[-o input.c -Dlr.type=lalr input.y]])
+[mv input.c lalr.c]
+AT_CAPTURE_FILE([lalr.c])
+AT_BISON_CHECK([[-o input.c -Dlr.type=ielr input.y]])
+[mv input.c ielr.c]
+AT_CAPTURE_FILE([ielr.c])
+AT_CHECK([[diff lalr.c ielr.c]], [[0]])
+
+AT_CLEANUP
+
+
+
+## --------------------------------------- ##
+## %error-verbose and YYSTACK_USE_ALLOCA. ##
+## --------------------------------------- ##
+
+AT_SETUP([[%error-verbose and YYSTACK_USE_ALLOCA]])
+
+AT_BISON_OPTION_PUSHDEFS
+AT_DATA_GRAMMAR([input.y],
+[[%code {
+ #include <stdio.h>
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
+ #define YYSTACK_USE_ALLOCA 1
+}
+
+%error-verbose
+
+%%
+
+start: check syntax_error syntax_error ;
+
+check:
+{
+ if (128 < sizeof yymsgbuf)
+ {
+ fprintf (stderr,
+ "The initial size of yymsgbuf in yyparse has increased\n"
+ "since this test group was last updated. As a result,\n"
+ "this test group may no longer manage to induce a\n"
+ "reallocation of the syntax error message buffer.\n"
+ "This test group must be adjusted to produce a longer\n"
+ "error message.\n");
+ YYABORT;
+ }
+}
+;
+
+// Induce a syntax error message whose total length is more than
+// sizeof yymsgbuf in yyparse. Each token here is 64 bytes.
+syntax_error:
+ "123456789112345678921234567893123456789412345678951234567896123A"
+| "123456789112345678921234567893123456789412345678951234567896123B"
+| error 'a' 'b' 'c'
+;
+
+%%
+
+]AT_YYERROR_DEFINE[
+/* Induce two syntax error messages (which requires full error
+ recovery by shifting 3 tokens) in order to detect any loss of the
+ reallocated buffer. */
+]AT_YYLEX_DEFINE([abc])[
+int
+main (void)
+{
+ return yyparse ();
+}
+]])
+AT_BISON_OPTION_POPDEFS
+
+AT_BISON_CHECK([[-o input.c input.y]])
+AT_COMPILE([[input]])
+AT_PARSER_CHECK([[./input]], [[1]], [],
+[[syntax error, unexpected 'a', expecting 123456789112345678921234567893123456789412345678951234567896123A or 123456789112345678921234567893123456789412345678951234567896123B
+syntax error, unexpected $end, expecting 123456789112345678921234567893123456789412345678951234567896123A or 123456789112345678921234567893123456789412345678951234567896123B
+]])
+
+AT_CLEANUP
+
+
+
+## ------------------------- ##
+## %error-verbose overflow. ##
+## ------------------------- ##
+
+# Imagine the case where YYSTACK_ALLOC_MAXIMUM = YYSIZE_MAXIMUM and an
+# invocation of yysyntax_error has caused yymsg_alloc to grow to exactly
+# YYSTACK_ALLOC_MAXIMUM (perhaps because the normal doubling of size had
+# to be clipped to YYSTACK_ALLOC_MAXIMUM). In an old version of yacc.c,
+# a subsequent invocation of yysyntax_error that overflows during its
+# size calculation would return YYSIZE_MAXIMUM to yyparse. Then,
+# yyparse would invoke yyerror using the old contents of yymsg.
+
+AT_SETUP([[%error-verbose overflow]])
+AT_BISON_OPTION_PUSHDEFS
+AT_DATA_GRAMMAR([input.y],
+[[%code {
+ #include <stdio.h>
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
+
+ /* This prevents this test case from having to induce error messages
+ large enough to overflow size_t. */
+ #define YYSIZE_T unsigned char
+
+ /* Bring in malloc and set EXIT_SUCCESS so yacc.c doesn't try to
+ provide a malloc prototype using our YYSIZE_T. */
+ #include <stdlib.h>
+ #ifndef EXIT_SUCCESS
+ # define EXIT_SUCCESS 0
+ #endif
+
+ /* Max depth is usually much smaller than YYSTACK_ALLOC_MAXIMUM, and
+ we don't want gcc to warn everywhere this constant would be too big
+ to make sense for our YYSIZE_T. */
+ #define YYMAXDEPTH 100
+}
+
+%error-verbose
+
+%%
+
+start: syntax_error1 check syntax_error2 ;
+
+// Induce a syntax error message whose total length causes yymsg in
+// yyparse to be reallocated to size YYSTACK_ALLOC_MAXIMUM, which
+// should be 255. Each token here is 64 bytes.
+syntax_error1:
+ "123456789112345678921234567893123456789412345678951234567896123A"
+| "123456789112345678921234567893123456789412345678951234567896123B"
+| "123456789112345678921234567893123456789412345678951234567896123C"
+| error 'a' 'b' 'c'
+;
+
+check:
+{
+ if (yymsg_alloc != YYSTACK_ALLOC_MAXIMUM
+ || YYSTACK_ALLOC_MAXIMUM != YYSIZE_MAXIMUM
+ || YYSIZE_MAXIMUM != 255)
+ {
+ fprintf (stderr,
+ "The assumptions of this test group are no longer\n"
+ "valid, so it may no longer catch the error it was\n"
+ "designed to catch. Specifically, the following\n"
+ "values should all be 255:\n\n");
+ fprintf (stderr, " yymsg_alloc = %d\n", yymsg_alloc);
+ fprintf (stderr, " YYSTACK_ALLOC_MAXIMUM = %d\n",
+ YYSTACK_ALLOC_MAXIMUM);
+ fprintf (stderr, " YYSIZE_MAXIMUM = %d\n", YYSIZE_MAXIMUM);
+ YYABORT;
+ }
+}
+;
+
+// Now overflow.
+syntax_error2:
+ "123456789112345678921234567893123456789412345678951234567896123A"
+| "123456789112345678921234567893123456789412345678951234567896123B"
+| "123456789112345678921234567893123456789412345678951234567896123C"
+| "123456789112345678921234567893123456789412345678951234567896123D"
+| "123456789112345678921234567893123456789412345678951234567896123E"
+;
+
+%%
+
+]AT_YYERROR_DEFINE[
+/* Induce two syntax error messages (which requires full error
+ recovery by shifting 3 tokens). */
+]AT_YYLEX_DEFINE([abc])[
+int
+main (void)
+{
+ /* Push parsers throw away the message buffer between tokens, so skip
+ this test under maintainer-push-check. */
+ if (YYPUSH)
+ return 77;
+ return yyparse ();
+}
+]])
+
+AT_BISON_CHECK([[-o input.c input.y]])
+
+# gcc warns about tautologies and fallacies involving comparisons for
+# unsigned char. However, it doesn't produce these same warnings for
+# size_t and many other types when the warnings would seem to make just
+# as much sense. We ignore the warnings.
+[CFLAGS="$NO_WERROR_CFLAGS"]
+AT_COMPILE([[input]])
+
+AT_PARSER_CHECK([[./input]], [[2]], [],
+[[syntax error, unexpected 'a', expecting 123456789112345678921234567893123456789412345678951234567896123A or 123456789112345678921234567893123456789412345678951234567896123B or 123456789112345678921234567893123456789412345678951234567896123C
+syntax error
+memory exhausted
+]])
+AT_BISON_OPTION_POPDEFS
+AT_CLEANUP
+
+
+
+## ------------------------ ##
+## LAC: Exploratory stack. ##
+## ------------------------ ##
+
+AT_SETUP([[LAC: Exploratory stack]])
+
+m4_pushdef([AT_LAC_CHECK], [
+
+AT_BISON_OPTION_PUSHDEFS([$1])
+
+AT_DATA_GRAMMAR([input.y],
+[[%code {
+ #include <stdio.h>
+ ]AT_YYERROR_DECLARE[
+ int yylex (]AT_PURE_IF([[YYSTYPE *]], [[void]])[);
+}
+
+]$1[
+%error-verbose
+%token 'c'
+
+%%
+
+// default reductions in inconsistent states
+// v v v v v v v v v v v v v v
+S: A B A A B A A A A B A A A A A A A B C C A A A A A A A A A A A A B ;
+// ^ ^ ^
+// LAC reallocs
+
+A: 'a' | /*empty*/ { printf ("inconsistent default reduction\n"); } ;
+B: 'b' ;
+C: /*empty*/ { printf ("consistent default reduction\n"); } ;
+
+%%
+]AT_YYERROR_DEFINE[
+int
+yylex (]AT_PURE_IF([[YYSTYPE *v]], [[void]])[)
+{
+ static char const *input = "bbbbc";]AT_PURE_IF([[
+ *v = 0;]])[
+ return *input++;
+}
+
+int
+main (void)
+{
+ yydebug = 1;
+ return yyparse ();
+}
+]])
+
+AT_BISON_CHECK([[-Dparse.lac=full -Dparse.lac.es-capacity-initial=1 \
+ -Dparse.lac.memory-trace=full \
+ -t -o input.c input.y]], [[0]], [],
+[[input.y: conflicts: 21 shift/reduce
+]])
+AT_COMPILE([[input]])
+AT_PARSER_CHECK([[./input > stdout.txt 2> stderr.txt]], [[1]])
+
+# Make sure syntax error doesn't forget that 'a' is expected. It would
+# be forgotten without lookahead correction.
+AT_CHECK([[grep 'syntax error,' stderr.txt]], [[0]],
+[[syntax error, unexpected 'c', expecting 'a' or 'b'
+]])
+
+# Check number of default reductions in inconsistent states to be sure
+# syntax error is detected before unnecessary reductions are performed.
+AT_CHECK([[perl -0777 -ne 'print s/inconsistent default reduction//g;' \
+ < stdout.txt || exit 77]], [[0]], [[14]])
+
+# Check number of default reductions in consistent states to be sure
+# it is performed before the syntax error is detected.
+AT_CHECK([[perl -0777 -ne 'print s/\bconsistent default reduction//g;' \
+ < stdout.txt || exit 77]], [[0]], [[2]])
+
+# Check number of reallocs to be sure reallocated memory isn't somehow
+# lost between LAC invocations.
+AT_CHECK([[perl -0777 -ne 'print s/\(realloc//g;' < stderr.txt \
+ || exit 77]], [[0]], [[3]])
+
+AT_BISON_OPTION_POPDEFS
+])
+
+AT_LAC_CHECK([[%define api.push-pull pull]])
+AT_LAC_CHECK([[%define api.push-pull pull %define api.pure]])
+AT_LAC_CHECK([[%define api.push-pull both]])
+AT_LAC_CHECK([[%define api.push-pull both %define api.pure]])
+
+m4_popdef([AT_LAC_CHECK])
+
+AT_CLEANUP
+
+
+
+## ------------------------ ##
+## LAC: Memory exhaustion. ##
+## ------------------------ ##
+
+AT_SETUP([[LAC: Memory exhaustion]])
+
+m4_pushdef([AT_LAC_CHECK],
+[AT_BISON_OPTION_PUSHDEFS
+AT_DATA_GRAMMAR([input.y],
+[[%code {
+ #include <stdio.h>
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
+ #define YYMAXDEPTH 8
+}
+
+%error-verbose
+
+%%
+
+S: A A A A A A A A A ;
+A: /*empty*/ | 'a' ;
+
+%%
+]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE([$1])[
+int
+main (void)
+{
+ yydebug = 1;
+ return yyparse ();
+}
+]])
+
+AT_BISON_CHECK([[-Dparse.lac=full -Dparse.lac.es-capacity-initial=1 \
+ -t -o input.c input.y]], [[0]], [],
+[[input.y: conflicts: 8 shift/reduce
+]])
+AT_COMPILE([[input]])
+AT_BISON_OPTION_POPDEFS
+])
+
+# Check for memory exhaustion during parsing.
+AT_LAC_CHECK([])
+AT_PARSER_CHECK([[./input]], [[2]], [],
+[[Starting parse
+Entering state 0
+Reading a token: Now at end of input.
+LAC: initial context established for $end
+LAC: checking lookahead $end: R2 G3 R2 G5 R2 G6 R2 G7 R2 G8 R2 G9 R2 G10 R2 G11 R2 (max size exceeded)
+memory exhausted
+Cleanup: discarding lookahead token $end ()
+Stack now 0
+]])
+
+# Induce an immediate syntax error with an undefined token, and check
+# for memory exhaustion while building syntax error message.
+AT_LAC_CHECK([z], [[0]])
+AT_PARSER_CHECK([[./input]], [[2]], [],
+[[Starting parse
+Entering state 0
+Reading a token: Next token is token $undefined ()
+LAC: initial context established for $undefined
+LAC: checking lookahead $undefined: Always Err
+Constructing syntax error message
+LAC: checking lookahead $end: R2 G3 R2 G5 R2 G6 R2 G7 R2 G8 R2 G9 R2 G10 R2 G11 R2 (max size exceeded)
+syntax error
+memory exhausted
+Cleanup: discarding lookahead token $undefined ()
+Stack now 0
+]])
+
+m4_popdef([AT_LAC_CHECK])
+
+AT_CLEANUP