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Fix test failure reported by Tom Lane in

Browse Source 
<http://lists.gnu.org/archive/html/bug-bison/2006-10/msg00000.html>
and try to make such failures easier to catch in the future.
* data/glr.c (YYTRANSLATE): Don't check for nonpositive arg;
that's now the caller's responsibility.
(yyprocessOneStack, yyrecoverSyntaxError, yyparse):
Set yychar = YYEOF if it's negative.
* tests/actions.at (yylex): Abort if asked to read past EOF.
* tests/conflicts.at (yylex): Likewise.
* tests/cxx-type.at (yylex): Likewise.
* tests/glr-regression.at (yylex): Likewise.
* tests/input.at (yylex): Likewise.
* tests/regression.at (yylex): Likewise.
* tests/torture.at (yylex): Likewise.
This commit is contained in:
Paul Eggert
2006-10-06 06:57:00 +00:00
parent 0e2f006a23
commit cf8067530b
9 changed files with 203 additions and 72 deletions
Download Patch File Download Diff File Expand all files Collapse all files

17
ChangeLog
View File

@@ -1,3 +1,20 @@
2006-10-05 Paul Eggert <eggert@cs.ucla.edu>
Fix test failure reported by Tom Lane in
<http://lists.gnu.org/archive/html/bug-bison/2006-10/msg00000.html>
and try to make such failures easier to catch in the future.
* data/glr.c (YYTRANSLATE): Don't check for nonpositive arg;
that's now the caller's responsibility.
(yyprocessOneStack, yyrecoverSyntaxError, yyparse):
Set yychar = YYEOF if it's negative.
* tests/actions.at (yylex): Abort if asked to read past EOF.
* tests/conflicts.at (yylex): Likewise.
* tests/cxx-type.at (yylex): Likewise.
* tests/glr-regression.at (yylex): Likewise.
* tests/input.at (yylex): Likewise.
* tests/regression.at (yylex): Likewise.
* tests/torture.at (yylex): Likewise.
2006-10-01 Paul Eggert <eggert@cs.ucla.edu> 2006-10-01 Paul Eggert <eggert@cs.ucla.edu>
Fix problems with translating English-language diagnostics. Fix problems with translating English-language diagnostics.

39
data/glr.c
View File

@@ -346,8 +346,7 @@ static YYSTYPE yyval_default;
#define YYMAXUTOK ]b4_user_token_number_max[ #define YYMAXUTOK ]b4_user_token_number_max[
#define YYTRANSLATE(YYX) \ #define YYTRANSLATE(YYX) \
((YYX <= 0) ? YYEOF : \ ((unsigned int) (YYX) <= YYMAXUTOK ? yytranslate[YYX] : YYUNDEFTOK)
(unsigned int) (YYX) <= YYMAXUTOK ? yytranslate[YYX] : YYUNDEFTOK)
/* YYTRANSLATE[YYLEX] -- Bison symbol number corresponding to YYLEX. */ /* YYTRANSLATE[YYLEX] -- Bison symbol number corresponding to YYLEX. */
static const ]b4_int_type_for([b4_translate])[ yytranslate[] = static const ]b4_int_type_for([b4_translate])[ yytranslate[] =
@@ -2040,11 +2039,19 @@ yyprocessOneStack (yyGLRStack* yystackp, size_t yyk,
{ {
YYDPRINTF ((stderr, "Reading a token: ")); YYDPRINTF ((stderr, "Reading a token: "));
yychar = YYLEX; yychar = YYLEX;
}
if (yychar <= YYEOF)
{
yychar = yytoken = YYEOF;
YYDPRINTF ((stderr, "Now at end of input.\n"));
}
else
{
yytoken = YYTRANSLATE (yychar); yytoken = YYTRANSLATE (yychar);
YY_SYMBOL_PRINT ("Next token is", yytoken, &yylval, &yylloc); YY_SYMBOL_PRINT ("Next token is", yytoken, &yylval, &yylloc);
} }
else
yytoken = YYTRANSLATE (yychar);
yygetLRActions (yystate, yytoken, &yyaction, &yyconflicts); yygetLRActions (yystate, yytoken, &yyaction, &yyconflicts);
while (*yyconflicts != 0) while (*yyconflicts != 0)
@@ -2210,8 +2217,16 @@ yyrecoverSyntaxError (yyGLRStack* yystackp]b4_user_formals[)
} }
YYDPRINTF ((stderr, "Reading a token: ")); YYDPRINTF ((stderr, "Reading a token: "));
yychar = YYLEX; yychar = YYLEX;
yytoken = YYTRANSLATE (yychar); if (yychar <= YYEOF)
YY_SYMBOL_PRINT ("Next token is", yytoken, &yylval, &yylloc); {
yychar = yytoken = YYEOF;
YYDPRINTF ((stderr, "Now at end of input.\n"));
}
else
{
yytoken = YYTRANSLATE (yychar);
YY_SYMBOL_PRINT ("Next token is", yytoken, &yylval, &yylloc);
}
yyj = yypact[yystackp->yytops.yystates[0]->yylrState]; yyj = yypact[yystackp->yytops.yystates[0]->yylrState];
if (yyis_pact_ninf (yyj)) if (yyis_pact_ninf (yyj))
return; return;
@@ -2363,11 +2378,19 @@ m4_popdef([b4_at_dollar])])dnl
{ {
YYDPRINTF ((stderr, "Reading a token: ")); YYDPRINTF ((stderr, "Reading a token: "));
yychar = YYLEX; yychar = YYLEX;
}
if (yychar <= YYEOF)
{
yychar = yytoken = YYEOF;
YYDPRINTF ((stderr, "Now at end of input.\n"));
}
else
{
yytoken = YYTRANSLATE (yychar); yytoken = YYTRANSLATE (yychar);
YY_SYMBOL_PRINT ("Next token is", yytoken, &yylval, &yylloc); YY_SYMBOL_PRINT ("Next token is", yytoken, &yylval, &yylloc);
} }
else
yytoken = YYTRANSLATE (yychar);
yygetLRActions (yystate, yytoken, &yyaction, &yyconflicts); yygetLRActions (yystate, yytoken, &yyaction, &yyconflicts);
if (*yyconflicts != 0) if (*yyconflicts != 0)
break; break;

45
tests/actions.at
View File

@@ -55,8 +55,11 @@ exp: { putchar ('0'); }
static int static int
yylex (void) yylex (void)
{ {
static const char *input = "123456789"; static char const input[] = "123456789";
return *input++; static size_t toknum;
if (! (toknum < sizeof input))
abort ();
return input[toknum++];
} }
static void static void
@@ -131,6 +134,9 @@ sum_of_the_five_previous_values:
static int static int
yylex (void) yylex (void)
{ {
static int called;
if (called++)
abort ();
return EOF; return EOF;
} }
@@ -175,6 +181,7 @@ AT_DATA_GRAMMAR([[input.y]],
[[%start-header { [[%start-header {
#include <stdio.h> #include <stdio.h>
#include <stdlib.h> #include <stdlib.h>
#include <string.h>
#include <assert.h> #include <assert.h>
#define YYINITDEPTH 10 #define YYINITDEPTH 10
@@ -310,6 +317,8 @@ yylex (]AT_LEX_FORMALS[)
AT_LOC.last_line = AT_LOC.last_column = AT_LOC.first_line + 9; AT_LOC.last_line = AT_LOC.last_column = AT_LOC.first_line + 9;
])[ ])[
if (! (0 <= c && c <= strlen (source)))
abort ();
if (source[c]) if (source[c])
printf ("sending: '%c'", source[c]); printf ("sending: '%c'", source[c]);
else else
@@ -623,11 +632,13 @@ start: 'a' 'b' 'c' 'd' 'e' { $$ = 'S'; USE(($1, $2, $3, $4, $5)); } ;
static int static int
yylex (void) yylex (void)
{ {
static const char *input = "abcd"; static char const input[] = "abcd";
static int column = 1; static size_t toknum;
yylval = *input++; if (! (toknum < sizeof input))
abort ();
yylval = input[toknum++];
yylloc.first_line = yylloc.last_line = 1; yylloc.first_line = yylloc.last_line = 1;
yylloc.first_column = yylloc.last_column = column++; yylloc.first_column = yylloc.last_column = toknum;
return yylval; return yylval;
} }
@@ -741,8 +752,11 @@ start:
static int static int
yylex (void) yylex (void)
{ {
static const char *input = "abcdef"; static char const input[] = "abcdef";
return *input++; static size_t toknum;
if (! (toknum < sizeof input))
abort ();
return input[toknum++];
} }
static void static void
@@ -851,6 +865,9 @@ start: { $$ = 'S'; } ;
static int static int
yylex (void) yylex (void)
{ {
static int called;
if (called++)
abort ();
yylval = 'E'; yylval = 'E';
yylloc.first_line = yylloc.last_line = 1; yylloc.first_line = yylloc.last_line = 1;
yylloc.first_column = yylloc.last_column = 1; yylloc.first_column = yylloc.last_column = 1;
@@ -915,6 +932,7 @@ AT_DATA_GRAMMAR([[input.y]],
%{ %{
# include <stdio.h> # include <stdio.h>
# include <stdlib.h>
static void yyerror (const char *msg); static void yyerror (const char *msg);
static int yylex (void); static int yylex (void);
# define USE(SYM) # define USE(SYM)
@@ -941,8 +959,11 @@ start:
static int static int
yylex (void) yylex (void)
{ {
static const char *input = "abd"; static char const input[] = "abd";
yylval = *input++; static size_t toknum;
if (! (toknum < sizeof input))
abort ();
yylval = input[toknum++];
return yylval; return yylval;
} }
@@ -1025,6 +1046,7 @@ AT_DATA_GRAMMAR([[input.y]],
%{ %{
# include <stdio.h> # include <stdio.h>
# include <stdlib.h>
static void yyerror (const char *msg); static void yyerror (const char *msg);
static int yylex (void); static int yylex (void);
# define USE(SYM) # define USE(SYM)
@@ -1051,6 +1073,9 @@ start: { USE($$); } ;
static int static int
yylex (void) yylex (void)
{ {
static int called;
if (called++)
abort ();
return 0; return 0;
} }

15
tests/conflicts.at
View File

@@ -56,6 +56,7 @@ AT_DATA_GRAMMAR([input.y],
%{ %{
#include <stdio.h> #include <stdio.h>
#include <stdlib.h> #include <stdlib.h>
#include <string.h>
#define YYERROR_VERBOSE 1 #define YYERROR_VERBOSE 1
static void static void
@@ -65,16 +66,15 @@ yyerror (const char *msg)
} }
/* The current argument. */ /* The current argument. */
static const char *input = NULL; static const char *input;
static int static int
yylex (void) yylex (void)
{ {
/* No token stands for end of file. */ static size_t toknum;
if (input && *input) if (! (toknum <= strlen (input)))
return *input++; abort ();
else return input[toknum++];
return 0;
} }
%} %}
@@ -90,8 +90,7 @@ expr: expr '<' expr
int int
main (int argc, const char *argv[]) main (int argc, const char *argv[])
{ {
if (argc > 1) input = argc <= 1 ? "" : argv[1];
input = argv[1];
return yyparse (); return yyparse ();
} }
]]) ]])

2
tests/cxx-type.at
View File

@@ -163,6 +163,8 @@ yylex (LEX_PARAMETERS)
while (1) while (1)
{ {
if (feof (stdin))
abort ();
c = getchar (); c = getchar ();
switch (c) switch (c)
{ {

112
tests/glr-regression.at
View File

@@ -30,6 +30,7 @@ AT_DATA_GRAMMAR([glr-regr1.y],
%{ %{
#include <stdio.h> #include <stdio.h>
#include <stdlib.h>
#define YYSTYPE int #define YYSTYPE int
static YYSTYPE exprMerge (YYSTYPE x0, YYSTYPE x1); static YYSTYPE exprMerge (YYSTYPE x0, YYSTYPE x1);
@@ -82,7 +83,10 @@ yylex (void)
{ {
for (;;) for (;;)
{ {
int ch = getchar (); int ch;
if (feof (stdin))
abort ();
ch = getchar ();
if (ch == EOF) if (ch == EOF)
return 0; return 0;
else if (ch == 'B' || ch == 'P') else if (ch == 'B' || ch == 'P')
@@ -168,13 +172,15 @@ var_printer: 'v'
%% %%
FILE *input = NULL; FILE *input;
int int
yylex (void) yylex (void)
{ {
char buf[50]; char buf[50];
char *s; char *s;
if (feof (stdin))
abort ();
switch (fscanf (input, " %1[a-z,]", buf)) { switch (fscanf (input, " %1[a-z,]", buf)) {
case 1: case 1:
return buf[0]; return buf[0];
@@ -237,6 +243,7 @@ AT_DATA_GRAMMAR([glr-regr3.y],
%{ %{
#include <stdio.h> #include <stdio.h>
#include <stdlib.h>
#include <stdarg.h> #include <stdarg.h>
static int MergeRule (int x0, int x1); static int MergeRule (int x0, int x1);
@@ -299,6 +306,8 @@ int T[] = { T1, T2, T3, T4 };
int yylex (void) int yylex (void)
{ {
char inp[3]; char inp[3];
if (feof (stdin))
abort ();
if (fscanf (input, "%2s", inp) == EOF) if (fscanf (input, "%2s", inp) == EOF)
return 0; return 0;
switch (inp[0]) switch (inp[0])
@@ -375,8 +384,11 @@ B: 'a' { $$ = make_value ("B", "'a'"); } ;
static int static int
yylex (void) yylex (void)
{ {
static char const *input = "a"; static char const input[] = "a";
return *input++; static size_t toknum;
if (! (toknum < sizeof input))
abort ();
return input[toknum++];
} }
int int
@@ -465,8 +477,11 @@ start:
static int static int
yylex (void) yylex (void)
{ {
static char const *input = "a"; static char const input[] = "a";
return *input++; static size_t toknum;
if (! (toknum < sizeof input))
abort ();
return input[toknum++];
} }
static void static void
@@ -527,8 +542,11 @@ start: 'a' | 'a' ;
static int static int
yylex (void) yylex (void)
{ {
static char const *input = "a"; static char const input[] = "a";
return *input++; static size_t toknum;
if (! (toknum < sizeof input))
abort ();
return input[toknum++];
} }
static void static void
@@ -697,6 +715,8 @@ int yylex (void)
lexIndex += 1; lexIndex += 1;
switch (lexIndex) switch (lexIndex)
{ {
default:
abort ();
case 1: case 1:
yylloc.first_column = 1; yylloc.first_column = 1;
yylloc.last_column = 9; yylloc.last_column = 9;
@@ -705,7 +725,7 @@ int yylex (void)
yylloc.first_column = 13; yylloc.first_column = 13;
yylloc.last_column = 17; yylloc.last_column = 17;
return T_PORT; return T_PORT;
default: case 3:
return 0; return 0;
} }
} }
@@ -822,6 +842,7 @@ AT_SETUP([Corrupted semantic options if user action cuts parse])
AT_DATA_GRAMMAR([glr-regr10.y], AT_DATA_GRAMMAR([glr-regr10.y],
[[ [[
%{ %{
# include <stdlib.h>
# include <stdio.h> # include <stdio.h>
static void yyerror (char const *); static void yyerror (char const *);
static int yylex (void); static int yylex (void);
@@ -851,6 +872,9 @@ yyerror (char const *msg)
static int static int
yylex (void) yylex (void)
{ {
static int called;
if (called++)
abort ();
return 0; return 0;
} }
@@ -913,8 +937,11 @@ yyerror (char const *msg)
static int static int
yylex (void) yylex (void)
{ {
static char const *input = "a"; static char const input[] = "a";
return *input++; static size_t toknum;
if (! (toknum < sizeof input))
abort ();
return input[toknum++];
} }
int int
@@ -1030,10 +1057,12 @@ static int
yylex (void) yylex (void)
{ {
static int const input[] = { PARENT_RHS_AFTER, 0 }; static int const input[] = { PARENT_RHS_AFTER, 0 };
static const int *inputp = input; static size_t toknum;
if (*inputp == PARENT_RHS_AFTER) if (! (toknum < sizeof input / sizeof *input))
abort ();
if (input[toknum] == PARENT_RHS_AFTER)
parent_rhs_after_value = 1; parent_rhs_after_value = 1;
return *inputp++; return input[toknum++];
} }
int int
@@ -1149,12 +1178,14 @@ yyerror (char const *msg)
static int static int
yylex (void) yylex (void)
{ {
static char const *input = "ab"; static char const input[] = "ab";
static int i = 0; static size_t toknum;
if (! (toknum < sizeof input))
abort ();
yylloc.first_line = yylloc.last_line = 1; yylloc.first_line = yylloc.last_line = 1;
yylloc.first_column = yylloc.last_column = i + 1; yylloc.first_column = yylloc.last_column = toknum + 1;
yylval.value = input[i] + 'A' - 'a'; yylval.value = input[toknum] + 'A' - 'a';
return input[i++]; return input[toknum++];
} }
static void static void
@@ -1235,6 +1266,7 @@ AT_DATA_GRAMMAR([glr-regr14.y],
%union { char value; } %union { char value; }
%{ %{
#include <stdlib.h>
#include <stdio.h> #include <stdio.h>
static void yyerror (char const *); static void yyerror (char const *);
static int yylex (void); static int yylex (void);
@@ -1355,12 +1387,14 @@ yyerror (char const *msg)
static int static int
yylex (void) yylex (void)
{ {
static char const *input = "abcdddd"; static char const input[] = "abcdddd";
static int i = 0; static size_t toknum;
if (! (toknum < sizeof input))
abort ();
yylloc.first_line = yylloc.last_line = 1; yylloc.first_line = yylloc.last_line = 1;
yylloc.first_column = yylloc.last_column = i + 1; yylloc.first_column = yylloc.last_column = toknum + 1;
yylval.value = input[i] + 'A' - 'a'; yylval.value = input[toknum] + 'A' - 'a';
return input[i++]; return input[toknum++];
} }
static void static void
@@ -1484,6 +1518,9 @@ yyerror (char const *msg)
static int static int
yylex (void) yylex (void)
{ {
static int called;
if (called++)
abort ();
return 0; return 0;
} }
@@ -1547,10 +1584,13 @@ yyerror (char const *msg)
static int static int
yylex (void) yylex (void)
{ {
static char const *input = "ab"; static char const input[] = "ab";
if (*input == 'b') static size_t toknum;
if (! (toknum < sizeof input))
abort ();
if (input[toknum] == 'b')
lookahead_value = 1; lookahead_value = 1;
return *input++; return input[toknum++];
} }
int int
@@ -1636,12 +1676,14 @@ static int
yylex (YYSTYPE *lvalp, YYLTYPE *llocp) yylex (YYSTYPE *lvalp, YYLTYPE *llocp)
{ {
static char const input[] = "ab"; static char const input[] = "ab";
static char const *inputp = input; static size_t toknum;
if (! (toknum < sizeof input))
abort ();
lvalp->dummy = 0; lvalp->dummy = 0;
llocp->first_line = llocp->last_line = 2; llocp->first_line = llocp->last_line = 2;
llocp->first_column = inputp - input + 1; llocp->first_column = toknum + 1;
llocp->last_column = llocp->first_column + 1; llocp->last_column = llocp->first_column + 1;
return *inputp++; return input[toknum++];
} }
int int
@@ -1672,6 +1714,7 @@ AT_DATA_GRAMMAR([glr-regr18.y],
[[%glr-parser [[%glr-parser
%{ %{
#include <stdlib.h>
static void yyerror (char const *); static void yyerror (char const *);
static int yylex (); static int yylex ();
%} %}
@@ -1703,6 +1746,9 @@ yyerror (char const *msg)
static int static int
yylex () yylex ()
{ {
static int called;
if (called++)
abort ();
return 0; return 0;
} }
@@ -1714,10 +1760,10 @@ main (void)
]]) ]])
AT_CHECK([[bison -o glr-regr18.c glr-regr18.y]], 1, [], AT_CHECK([[bison -o glr-regr18.c glr-regr18.y]], 1, [],
[glr-regr18.y:27.18-24: result type clash on merge function `merge': <type2> != <type1> [glr-regr18.y:28.18-24: result type clash on merge function `merge': <type2> != <type1>
glr-regr18.y:26.18-24: previous declaration
glr-regr18.y:28.13-19: result type clash on merge function `merge': <type3> != <type2>
glr-regr18.y:27.18-24: previous declaration glr-regr18.y:27.18-24: previous declaration
glr-regr18.y:29.13-19: result type clash on merge function `merge': <type3> != <type2>
glr-regr18.y:28.18-24: previous declaration
]) ])
AT_CLEANUP AT_CLEANUP

9
tests/input.at
View File

@@ -459,11 +459,14 @@ value_as_yystype (value val)
static int static int
yylex (void) yylex (void)
{ {
static const char *input = "@<:@\1\2$@{@oline@__@&t@oline__\ static char const input[] = "@<:@\1\2$@{@oline@__@&t@oline__\
#output "; /* " #output "; /* "
*/ */
yylval = value_as_yystype (*input); static size_t toknum;
return *input++; if (! (toknum < sizeof input))
abort ();
yylval = value_as_yystype (input[toknum]);
return input[toknum++];
} }
static void static void

19
tests/regression.at
View File

@@ -434,6 +434,7 @@ AT_SETUP([Token definitions])
# Bison managed, when fed with `%token 'f' "f"' to #define 'f'! # Bison managed, when fed with `%token 'f' "f"' to #define 'f'!
AT_DATA_GRAMMAR([input.y], AT_DATA_GRAMMAR([input.y],
[%{ [%{
#include <stdlib.h>
#include <stdio.h> #include <stdio.h>
void yyerror (const char *s); void yyerror (const char *s);
int yylex (void); int yylex (void);
@@ -457,6 +458,9 @@ yyerror (char const *s)
int int
yylex (void) yylex (void)
{ {
static int called;
if (called++)
abort ();
return SPECIAL; return SPECIAL;
} }
@@ -822,7 +826,8 @@ m4_define([_AT_DATA_DANCER_Y],
[%{ [%{
static int yylex (AT_LALR1_CC_IF([int *], [void])); static int yylex (AT_LALR1_CC_IF([int *], [void]));
AT_LALR1_CC_IF([], AT_LALR1_CC_IF([],
[#include <stdio.h> [#include <stdlib.h>
#include <stdio.h>
static void yyerror (const char *);]) static void yyerror (const char *);])
%} %}
$1 $1
@@ -896,12 +901,14 @@ yyerror (const char *s)
static int static int
yylex (AT_LALR1_CC_IF([int *lval], [void])) yylex (AT_LALR1_CC_IF([int *lval], [void]))
[{ [{
static int toknum = 0; static int const tokens[] =
static int tokens[] =
{ {
':', -1 ':', -1
}; };
static size_t toknum;
]AT_LALR1_CC_IF([*lval = 0; /* Pacify GCC. */])[ ]AT_LALR1_CC_IF([*lval = 0; /* Pacify GCC. */])[
if (! (toknum < sizeof tokens / sizeof *tokens))
abort ();
return tokens[toknum++]; return tokens[toknum++];
}] }]
@@ -993,12 +1000,14 @@ yyerror (const char *s)
static int static int
yylex (AT_LALR1_CC_IF([int *lval], [void])) yylex (AT_LALR1_CC_IF([int *lval], [void]))
[{ [{
static int toknum = 0; static int const tokens[] =
static int tokens[] =
{ {
1000, '+', '+', -1 1000, '+', '+', -1
}; };
static size_t toknum;
]AT_LALR1_CC_IF([*lval = 0; /* Pacify GCC. */])[ ]AT_LALR1_CC_IF([*lval = 0; /* Pacify GCC. */])[
if (! (toknum < sizeof tokens / sizeof *tokens))
abort ();
return tokens[toknum++]; return tokens[toknum++];
}] }]

17
tests/torture.at
View File

@@ -199,10 +199,11 @@ static int
yylex (void) yylex (void)
{ {
static int counter = 1; static int counter = 1;
if (counter > $max) if (counter <= $max)
return 0; return counter++;
else if (counter++ != $max + 1)
return counter++; abort ();
return 0;
} }
static void static void
@@ -331,7 +332,11 @@ yylex (void)
static int return_token = 1; static int return_token = 1;
static int counter = 1; static int counter = 1;
if (counter > $max) if (counter > $max)
return 0; {
if (counter++ != $max + 1)
abort ();
return 0;
}
if (return_token) if (return_token)
{ {
return_token = 0; return_token = 0;
@@ -412,6 +417,8 @@ yyerror (const char *msg)
static int static int
yylex (void) yylex (void)
{ {
if (yylval < 0)
abort ();
if (yylval--) if (yylval--)
return WAIT_FOR_EOF; return WAIT_FOR_EOF;
else else