mirror of
https://git.savannah.gnu.org/git/bison.git
synced 2026-03-09 12:23:04 +00:00
e0cb91a922
The CI has "failures" such as (253, "Null nonterminals"):
@@ -21,7 +21,7 @@
3: 3 b: . %empty
3: 4 c: . %empty
On Symbols: {A,}
-time limit exceeded: 6.000000
+time limit exceeded: 11.000000
First Example c • c A A $end
First derivation $accept ::=[ a ::=[ c d ::=[ a ::=[ b ::=[ • ] d ::=[ c A A ] ] ] ] $end ]
Second Example c • A $end
* tests/counterexample.at (AT_BISON_CHECK_CEX): New.
Use it to neutralize differences in timeout values.
612 lines
14 KiB
Plaintext
612 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([-Wcounterexample $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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[[Shift-Reduce Conflict:
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1: 3 a: A .
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1: 8 y: A . B
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On Symbol: 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: warning: 1 shift/reduce conflict [-Wconflicts-sr]
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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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[[Shift-Reduce Conflict:
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1: 7 a: A .
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1: 5 b: . B
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On Symbol: 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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input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
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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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[[Shift-Reduce Conflict:
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1: 4 x: . %empty
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1: 9 xby: . B
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On Symbol: B
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Example A • B y
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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:
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5: 4 x: . %empty
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5: 9 xby: . B
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On Symbol: 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: warning: 2 shift/reduce conflicts [-Wconflicts-sr]
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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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[[Shift-Reduce Conflict:
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2: 7 b: B .
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2: 9 bc: B . C
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On Symbol: 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: warning: 1 shift/reduce conflict [-Wconflicts-sr]
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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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[[Shift-Reduce Conflict:
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1: 5 x: A .
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1: 6 y: A . A B
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On Symbol: 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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input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
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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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[[Shift-Reduce Conflict:
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4: 3 r: b .
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4: 7 s: b . A xx y
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On Symbol: 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:
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10: 8 x: X .
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10: 9 xx: X . X
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On Symbol: 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: warning: 2 shift/reduce conflicts [-Wconflicts-sr]
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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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[[Reduce-Reduce Conflict:
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4: 1 a: A b .
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4: 3 b: b .
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On Symbols: {$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: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
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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 lr1 conflict. ##
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## ------------------------------- ##
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AT_SETUP([Non-unifying R/R lr1 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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[[Reduce-Reduce Conflict:
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2: 5 a: D .
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2: 6 b: D .
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On Symbols: {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: warning: 2 reduce/reduce conflicts [-Wconflicts-rr]
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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 lr2 conflict. ##
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## ------------------------------- ##
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AT_SETUP([Non-unifying R/R lr2 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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[[Shift-Reduce Conflict:
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5: 2 a: H i .
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5: 4 i: i . J K
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On Symbol: J
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time limit exceeded: 6.000000
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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: warning: 1 shift/reduce conflict [-Wconflicts-sr]
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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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[[Shift-Reduce Conflict:
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4: 7 a: A .
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4: 8 b: A . B C
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On Symbol: 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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input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
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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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[[Reduce-Reduce Conflict:
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3: 3 A: B .
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3: 5 A: . %empty
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On Symbols: {b,c,}
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Example B • b A A c A
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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:
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4: 4 A: C .
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4: 5 A: . %empty
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On Symbols: {b,c,}
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Example C • c A A b A
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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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input.y: warning: 4 reduce/reduce conflicts [-Wconflicts-rr]
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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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[[Reduce-Reduce Conflict:
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0: 3 b: . %empty
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0: 4 c: . %empty
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On Symbols: {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:
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2: 3 b: . %empty
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2: 4 c: . %empty
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On Symbols: {A,}
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time limit exceeded: 6.000000
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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:
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3: 3 b: . %empty
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3: 4 c: . %empty
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On Symbols: {A,}
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time limit exceeded: 6.000000
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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:
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6: 3 b: . %empty
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6: 6 d: c . A
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On Symbol: A
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time limit exceeded: 6.000000
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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:
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6: 3 b: . %empty
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6: 4 c: . %empty
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On Symbols: {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:
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6: 4 c: . %empty
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6: 6 d: c . A
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On Symbol: 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 ] ] ] ] $end ]
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Second Example b c • A
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Second derivation a ::=[ b d ::=[ c • A ] ]
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Reduce-Reduce Conflict:
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7: 1 a: b d .
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7: 7 d: d .
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On Symbols: {$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:
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8: 2 a: c d .
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8: 7 d: d .
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On Symbols: {$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: warning: 1 shift/reduce conflict [-Wconflicts-sr]
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input.y: warning: 6 reduce/reduce conflicts [-Wconflicts-rr]
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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]
|
|
]])
|
|
|
|
AT_CLEANUP
|
|
|
|
## --------------------------- ##
|
|
## Non-unifying Prefix Share. ##
|
|
## --------------------------- ##
|
|
|
|
AT_SETUP([Non-unifying Prefix Share])
|
|
AT_KEYWORDS([cex])
|
|
|
|
# Tests for a counterexample which should start its derivation
|
|
# at a shared symbol rather than the start symbol.
|
|
|
|
AT_DATA([[input.y]],
|
|
[[%token H J
|
|
%%
|
|
s: a | a J;
|
|
a: H i J J
|
|
i: %empty | i J;
|
|
]])
|
|
|
|
AT_BISON_CHECK_CEX([input.y], [], [],
|
|
[[Shift-Reduce Conflict:
|
|
7: 5 i: i J .
|
|
7: 3 a: H i J . J
|
|
On Symbol: J
|
|
Example H i J • J J
|
|
First derivation s ::=[ a ::=[ H i ::=[ i J • ] J J ] ]
|
|
Second derivation s ::=[ a ::=[ H i J • J ] J ]
|
|
|
|
input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
|
|
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], [], [],
|
|
[[Shift-Reduce Conflict:
|
|
3: 5 C: . %empty
|
|
3: 6 D: . d
|
|
On Symbol: d
|
|
Example a A • d
|
|
First derivation S ::=[ a A A ::=[ B ::=[ C ::=[ • ] ] ] D ::=[ d ] ]
|
|
Second derivation S ::=[ a A D ::=[ • d ] ]
|
|
|
|
input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
|
|
]])
|
|
|
|
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], [], [],
|
|
[[Shift-Reduce Conflict:
|
|
3: 5 C: . %empty
|
|
3: 6 D: . d
|
|
On Symbol: 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 ]
|
|
|
|
input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
|
|
]])
|
|
|
|
AT_CLEANUP
|