mirror of
https://git.savannah.gnu.org/git/bison.git
synced 2026-03-09 12:23:04 +00:00
b65bd16e45
Before this commit, on
%%
exp
: "if" exp "then" exp
| "if" exp "then" exp "else" exp
| exp "+" exp
| "num"
we used to not display the third counterexample below:
Shift/reduce conflict on token "+":
Example exp "+" exp . "+" exp
First derivation exp ::=[ exp ::=[ exp "+" exp . ] "+" exp ]
Second derivation exp ::=[ exp "+" exp ::=[ exp . "+" exp ] ]
Shift/reduce conflict on token "else":
Example "if" exp "then" "if" exp "then" exp . "else" exp
First derivation exp ::=[ "if" exp "then" exp ::=[ "if" exp "then" exp . ] "else" exp ]
Second derivation exp ::=[ "if" exp "then" exp ::=[ "if" exp "then" exp . "else" exp ] ]
Shift/reduce conflict on token "+":
Example "if" exp "then" exp . "+" exp
First derivation exp ::=[ exp ::=[ "if" exp "then" exp . ] "+" exp ]
Second derivation exp ::=[ "if" exp "then" exp ::=[ exp . "+" exp ] ]
Shift/reduce conflict on token "+":
Example "if" exp "then" exp "else" exp . "+" exp
First derivation exp ::=[ exp ::=[ "if" exp "then" exp "else" exp . ] "+" exp ]
Second derivation exp ::=[ "if" exp "then" exp "else" exp ::=[ exp . "+" exp ] ]
* src/counterexample.c (counterexample_report_state): Don't stop of
the first conflicts.
* tests/conflicts.at, tests/counterexample.at, tests/diagnostics.at,
* tests/report.at: Adjust.
547 lines
14 KiB
Plaintext
547 lines
14 KiB
Plaintext
# Exercising Bison on counterexamples. -*- Autotest -*-
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# Copyright (C) 2020 Free Software Foundation, Inc.
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# This program is free software: you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation, either version 3 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program. If not, see <http://www.gnu.org/licenses/>.
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AT_BANNER([[Counterexamples.]])
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m4_define([AT_BISON_CHECK_CEX],
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[AT_DATA([experr], [$4])
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sed -e ['s/time limit exceeded: [0-9][.0-9]*/time limit exceeded: XXX/g'] \
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experr >expout
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AT_BISON_CHECK([-Wcounterexamples $1], [$2], [$3], [stderr])
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AT_CHECK([[sed -e 's/time limit exceeded: [0-9][.0-9]*/time limit exceeded: XXX/g' stderr]],
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[], [expout])
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])
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## --------------------- ##
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## Simple Unifying S/R. ##
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## --------------------- ##
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AT_SETUP([Unifying S/R])
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AT_KEYWORDS([cex])
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AT_DATA([[input.y]],
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[[%token A B C
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%%
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s: a x | y c;
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a: A;
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c: C;
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x: B | B C;
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y: A | A B;
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]])
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AT_BISON_CHECK_CEX([input.y], [], [],
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[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
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Shift/reduce conflict on token B:
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Example A . B C
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First derivation s ::=[ a ::=[ A . ] x ::=[ B C ] ]
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Second derivation s ::=[ y ::=[ A . B ] c ::=[ C ] ]
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input.y:4.4: warning: rule useless in parser due to conflicts [-Wother]
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]])
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AT_CLEANUP
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## ------------------- ##
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## Deep Unifying S/R. ##
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## ------------------- ##
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AT_SETUP([Deep Unifying S/R])
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AT_KEYWORDS([cex])
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AT_DATA([[input.y]],
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[[%token A B C
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%%
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s: ac | a bc;
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ac: A ac C | b;
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b: B | B b;
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a: A | A a;
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bc: B bc C | B C;
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]])
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AT_BISON_CHECK_CEX([input.y], [], [],
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[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
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Shift/reduce conflict on token B:
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Example A . B C
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First derivation s ::=[ a ::=[ A . ] bc ::=[ B C ] ]
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Second derivation s ::=[ ac ::=[ A ac ::=[ b ::=[ . B ] ] C ] ]
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Shift/reduce conflict on token B:
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Example A A . B B C C
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First derivation s ::=[ a ::=[ A a ::=[ A . ] ] bc ::=[ B bc ::=[ B C ] C ] ]
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Second derivation s ::=[ ac ::=[ A ac ::=[ A ac ::=[ b ::=[ . b ::=[ B B ] ] ] C ] C ] ]
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input.y:6.4: warning: rule useless in parser due to conflicts [-Wother]
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]])
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AT_CLEANUP
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## ------------------------------------ ##
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## S/R Conflict with Nullable Symbols. ##
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## ------------------------------------ ##
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AT_SETUP([S/R Conflict with Nullable Symbols])
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AT_KEYWORDS([cex])
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AT_DATA([[input.y]],
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[[%token A B X Y
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%%
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s: ax by | A xby;
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ax: A x;
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x: %empty | X x;
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by: B y;
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y: %empty | Y y;
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xby: B | X xby Y;
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]])
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AT_BISON_CHECK_CEX([input.y], [], [],
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[[input.y: warning: 2 shift/reduce conflicts [-Wconflicts-sr]
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Shift/reduce conflict on token B:
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Example A . B
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First derivation s ::=[ ax ::=[ A x ::=[ . ] ] by ::=[ B y ::=[ ] ] ]
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Second derivation s ::=[ A xby ::=[ . B ] ]
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Shift/reduce conflict on token B:
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First example A X . B y $end
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First derivation $accept ::=[ s ::=[ ax ::=[ A x ::=[ X x ::=[ . ] ] ] by ::=[ B y ] ] $end ]
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Second example A X . B Y $end
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Second derivation $accept ::=[ s ::=[ A xby ::=[ X xby ::=[ . B ] Y ] ] $end ]
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input.y:5.4-9: warning: rule useless in parser due to conflicts [-Wother]
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]])
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AT_CLEANUP
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## ---------------------------- ##
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## Non-unifying Ambiguous S/R. ##
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## ---------------------------- ##
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AT_SETUP([Non-unifying Ambiguous S/R])
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AT_KEYWORDS([cex])
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AT_DATA([[input.y]],
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[[%token A B C D E
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%%
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g: s | x;
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s: A x E | A x D E;
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x: b cd | bc;
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b: B;
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cd: C D;
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bc: B C;
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]])
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AT_BISON_CHECK_CEX([input.y], [], [],
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[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
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Shift/reduce conflict on token C:
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First example B . C D $end
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First derivation $accept ::=[ g ::=[ x ::=[ b ::=[ B . ] cd ::=[ C D ] ] ] $end ]
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Second example B . C $end
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Second derivation $accept ::=[ g ::=[ x ::=[ bc ::=[ B . C ] ] ] $end ]
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input.y:6.4: warning: rule useless in parser due to conflicts [-Wother]
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]])
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AT_CLEANUP
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## ------------------------------ ##
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## Non-unifying Unambiguous S/R. ##
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## ------------------------------ ##
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AT_SETUP([Non-unifying Unambiguous S/R])
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AT_KEYWORDS([cex])
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AT_DATA([[input.y]],
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[[%token A B
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%%
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s: t | s t;
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t: x | y;
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x: A;
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y: A A B;
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]])
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AT_BISON_CHECK_CEX([input.y], [], [],
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[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
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Shift/reduce conflict on token A:
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First example A . A $end
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First derivation $accept ::=[ s ::=[ s ::=[ t ::=[ x ::=[ A . ] ] ] t ::=[ x ::=[ A ] ] ] $end ]
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Second example A . A B $end
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Second derivation $accept ::=[ s ::=[ t ::=[ y ::=[ A . A B ] ] ] $end ]
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]])
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AT_CLEANUP
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## ----------------------- ##
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## S/R after first token. ##
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## ----------------------- ##
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AT_SETUP([S/R after first token])
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AT_KEYWORDS([cex])
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AT_DATA([[input.y]],
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[[%token A B X Y
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%%
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a: r t | s;
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r: b;
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b: B;
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t: A xx | A x xy;
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s: b A xx y;
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x: X;
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xx: X X;
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xy: X Y;
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y: Y;
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]])
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AT_BISON_CHECK_CEX([input.y], [], [],
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[[input.y: warning: 2 shift/reduce conflicts [-Wconflicts-sr]
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Shift/reduce conflict on token A:
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Example b . A X X Y
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First derivation a ::=[ r ::=[ b . ] t ::=[ A x ::=[ X ] xy ::=[ X Y ] ] ]
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Second derivation a ::=[ s ::=[ b . xx ::=[ A X X ] y ::=[ Y ] ] ]
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Shift/reduce conflict on token X:
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First example X . X xy
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First derivation a ::=[ x ::=[ X . ] t ::=[ X xy ] ]
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Second example A X . X
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Second derivation a ::=[ t ::=[ A xx ::=[ X . X ] ] ]
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input.y:4.4: warning: rule useless in parser due to conflicts [-Wother]
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input.y:8.4: warning: rule useless in parser due to conflicts [-Wother]
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]])
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AT_CLEANUP
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## ----------------------------- ##
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## Unifying R/R counterexample. ##
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## ----------------------------- ##
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AT_SETUP([Unifying R/R counterexample])
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AT_KEYWORDS([cex])
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AT_DATA([[input.y]],
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[[%token A
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%%
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a : A b ;
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b : A | b;
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]])
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AT_BISON_CHECK_CEX([input.y], [], [],
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[[input.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
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Reduce/reduce conflict on token $end:
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Example A b .
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First derivation a ::=[ A b . ]
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Second derivation a ::=[ A b ::=[ b . ] ]
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input.y:4.9: warning: rule useless in parser due to conflicts [-Wother]
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]])
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AT_CLEANUP
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## --------------------------------- ##
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## Non-unifying R/R LR(1) conflict. ##
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## --------------------------------- ##
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AT_SETUP([Non-unifying R/R LR(1) conflict])
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AT_KEYWORDS([cex])
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AT_DATA([[input.y]],
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[[%token A B C D
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%%
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s: a A | B a C | b C | B b A;
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a: D;
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b: D;
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]])
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AT_BISON_CHECK_CEX([input.y], [], [],
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[[input.y: warning: 2 reduce/reduce conflicts [-Wconflicts-rr]
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Reduce/reduce conflict on tokens A, C:
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First example D . A $end
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First derivation $accept ::=[ s ::=[ a ::=[ D . ] A ] $end ]
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Second example B D . A $end
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Second derivation $accept ::=[ s ::=[ B b ::=[ D . ] A ] $end ]
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input.y:5.4: warning: rule useless in parser due to conflicts [-Wother]
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]])
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AT_CLEANUP
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## --------------------------------- ##
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## Non-unifying R/R LR(2) conflict. ##
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## --------------------------------- ##
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AT_SETUP([Non-unifying R/R LR(2) conflict])
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AT_KEYWORDS([cex])
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AT_DATA([[input.y]],
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[[%token H J K X
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%%
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s: a J;
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a: H i;
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i: X | i J K;
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]])
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AT_BISON_CHECK_CEX([input.y], [], [],
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[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
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Shift/reduce conflict on token J:
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time limit exceeded: XXX
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First example H i . J $end
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First derivation $accept ::=[ s ::=[ a ::=[ H i . ] J ] $end ]
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Second example H i . J K $end
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Second derivation $accept ::=[ a ::=[ H i ::=[ i . J K ] ] $end ]
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input.y:4.4-6: warning: rule useless in parser due to conflicts [-Wother]
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]])
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AT_CLEANUP
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## -------------------- ##
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## Cex Search Prepend. ##
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## -------------------- ##
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# Tests prepend steps in uniying counterexample
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# graph search
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AT_SETUP([Cex Search Prepend])
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AT_KEYWORDS([cex])
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AT_DATA([[input.y]],
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[[%token N A B C D
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%%
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s: n | n C;
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n: N n D | N n C | N a B | N b;
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a: A;
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b: A B C | A B D;
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]])
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AT_BISON_CHECK_CEX([input.y], [], [],
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[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
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Shift/reduce conflict on token B:
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Example N A . B C
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First derivation s ::=[ n ::=[ N a ::=[ A . ] B ] C ]
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Second derivation s ::=[ n ::=[ N b ::=[ A . B C ] ] ]
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Shift/reduce conflict on token B:
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Example N N A . B D C
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First derivation s ::=[ n ::=[ N n ::=[ N a ::=[ A . ] B ] D ] C ]
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Second derivation s ::=[ n ::=[ N n ::=[ N b ::=[ A . B D ] ] C ] ]
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input.y:5.4: warning: rule useless in parser due to conflicts [-Wother]
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]])
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AT_CLEANUP
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## ------------------- ##
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## R/R cex with prec. ##
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## ------------------- ##
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# Tests that counterexamples containing rules using
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# precedence/associativity directives work.
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AT_SETUP([R/R cex with prec])
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AT_KEYWORDS([cex])
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AT_DATA([[input.y]],
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[[%left b
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%right c
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%%
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S: B C | C B;
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A : B | C | %empty;
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B : A b A;
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C : A c A;
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]])
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AT_BISON_CHECK_CEX([input.y], [], [],
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[[input.y: warning: 4 reduce/reduce conflicts [-Wconflicts-rr]
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Reduce/reduce conflict on tokens b, c:
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Example B . b c
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First derivation S ::=[ B ::=[ A ::=[ B . ] b A ::=[ ] ] C ::=[ A ::=[ ] c A ::=[ ] ] ]
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Second derivation S ::=[ B C ::=[ A ::=[ B ::=[ A ::=[ . ] b A ::=[ ] ] ] c A ::=[ ] ] ]
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Reduce/reduce conflict on tokens b, c:
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Example C . c b
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First derivation S ::=[ C ::=[ A ::=[ C . ] c A ::=[ ] ] B ::=[ A ::=[ ] b A ::=[ ] ] ]
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Second derivation S ::=[ C B ::=[ A ::=[ C ::=[ A ::=[ . ] c A ::=[ ] ] ] b A ::=[ ] ] ]
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]])
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AT_CLEANUP
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## ------------------- ##
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## Null nonterminals. ##
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## ------------------- ##
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AT_SETUP([Null nonterminals])
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AT_KEYWORDS([cex])
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AT_DATA([[input.y]],
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[[%token A
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%%
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a : b d | c d ;
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b : ;
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c : ;
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d : a | c A | d;
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]])
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AT_BISON_CHECK_CEX([input.y], [], [],
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[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
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input.y: warning: 6 reduce/reduce conflicts [-Wconflicts-rr]
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Reduce/reduce conflict on token A:
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First example . c A A $end
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First derivation $accept ::=[ a ::=[ b ::=[ . ] d ::=[ c A A ] ] $end ]
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Second example . c A A $end
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Second derivation $accept ::=[ a ::=[ c ::=[ . ] d ::=[ c A A ] ] $end ]
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Reduce/reduce conflict on token A:
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time limit exceeded: XXX
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First example b . c A A $end
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First derivation $accept ::=[ a ::=[ b d ::=[ a ::=[ b ::=[ . ] d ::=[ c A A ] ] ] ] $end ]
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Second example b . A $end
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Second derivation $accept ::=[ a ::=[ b d ::=[ c ::=[ . ] A ] ] $end ]
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Reduce/reduce conflict on token A:
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time limit exceeded: XXX
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First example c . c A A $end
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First derivation $accept ::=[ a ::=[ c d ::=[ a ::=[ b ::=[ . ] d ::=[ c A A ] ] ] ] $end ]
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Second example c . A $end
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Second derivation $accept ::=[ a ::=[ c d ::=[ c ::=[ . ] A ] ] $end ]
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Shift/reduce conflict on token A:
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time limit exceeded: XXX
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First example b c . c A A $end
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First derivation $accept ::=[ a ::=[ b d ::=[ a ::=[ c d ::=[ a ::=[ b ::=[ . ] d ::=[ c A A ] ] ] ] ] ] $end ]
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Second example b c . A
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Second derivation a ::=[ b d ::=[ c . A ] ]
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Reduce/reduce conflict on token A:
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First example b c . c A A $end
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First derivation $accept ::=[ a ::=[ b d ::=[ a ::=[ c d ::=[ a ::=[ b ::=[ . ] d ::=[ c A A ] ] ] ] ] ] $end ]
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Second example b c . A $end
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Second derivation $accept ::=[ a ::=[ b d ::=[ a ::=[ c d ::=[ c ::=[ . ] A ] ] ] ] $end ]
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Shift/reduce conflict on token A:
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First example b c . A $end
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First derivation $accept ::=[ a ::=[ b d ::=[ a ::=[ c d ::=[ c ::=[ . ] A ] ] ] ] $end ]
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Second example b c . A
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Second derivation a ::=[ b d ::=[ c . A ] ]
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Reduce/reduce conflict on token $end:
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Example b d .
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First derivation a ::=[ b d . ]
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Second derivation a ::=[ b d ::=[ d . ] ]
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Reduce/reduce conflict on token $end:
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Example c d .
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First derivation a ::=[ c d . ]
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Second derivation a ::=[ c d ::=[ d . ] ]
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input.y:5.4: warning: rule useless in parser due to conflicts [-Wother]
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input.y:6.15: warning: rule useless in parser due to conflicts [-Wother]
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]])
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AT_CLEANUP
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## --------------------------- ##
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## Non-unifying Prefix Share. ##
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## --------------------------- ##
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AT_SETUP([Non-unifying Prefix Share])
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AT_KEYWORDS([cex])
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# Tests for a counterexample which should start its derivation
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# at a shared symbol rather than the start symbol.
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AT_DATA([[input.y]],
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[[%token H J
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%%
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s: a | a J;
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a: H i J J
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i: %empty | i J;
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]])
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AT_BISON_CHECK_CEX([input.y], [], [],
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[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
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Shift/reduce conflict on token J:
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Example H i J . J J
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First derivation s ::=[ a ::=[ H i ::=[ i J . ] J J ] ]
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Second derivation s ::=[ a ::=[ H i J . J ] J ]
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input.y:5.13-15: warning: rule useless in parser due to conflicts [-Wother]
|
|
]])
|
|
|
|
AT_CLEANUP
|
|
|
|
## -------------------- ##
|
|
## Deep Null Unifying. ##
|
|
## ---------------------##
|
|
|
|
# Tests that nested nullable nonterminals
|
|
# are derived correctly.
|
|
|
|
AT_SETUP([Deep Null Unifying])
|
|
AT_KEYWORDS([cex])
|
|
|
|
AT_DATA([[input.y]],
|
|
[[%token A D
|
|
%%
|
|
s: A a d | A a a d;
|
|
a: b;
|
|
b: c
|
|
c: %empty
|
|
d: D;
|
|
]])
|
|
|
|
AT_BISON_CHECK_CEX([input.y], [], [],
|
|
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
|
|
Shift/reduce conflict on token D:
|
|
Example A a . D
|
|
First derivation s ::=[ A a a ::=[ b ::=[ c ::=[ . ] ] ] d ::=[ D ] ]
|
|
Second derivation s ::=[ A a d ::=[ . D ] ]
|
|
|
|
]])
|
|
|
|
AT_CLEANUP
|
|
|
|
## ------------------------ ##
|
|
## Deep Null Non-unifying. ##
|
|
## -------------------------##
|
|
|
|
# Tests that expand_to_conflict works with nullable sybols
|
|
|
|
AT_SETUP([Deep Null Non-unifying])
|
|
AT_KEYWORDS([cex])
|
|
|
|
AT_DATA([[input.y]],
|
|
[[%token A D E
|
|
%%
|
|
s: A a d | A a a d E;
|
|
a: b;
|
|
b: c
|
|
c: %empty
|
|
d: D;
|
|
]])
|
|
|
|
AT_BISON_CHECK_CEX([input.y], [], [],
|
|
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
|
|
Shift/reduce conflict on token D:
|
|
First example A a . D E $end
|
|
First derivation $accept ::=[ s ::=[ A a a ::=[ b ::=[ c ::=[ . ] ] ] d ::=[ D ] E ] $end ]
|
|
Second example A a . D $end
|
|
Second derivation $accept ::=[ s ::=[ A a d ::=[ . D ] ] $end ]
|
|
|
|
]])
|
|
|
|
AT_CLEANUP
|