Fix precedence for end token.

Since Bison 2.3b, which restored the ability of precedence
directives to assign user token numbers, doing so for user token
number 0 has produced an assertion failure.
* NEWS (2.5): Document fix.
* src/symtab.c (symbol_user_token_number_set): In the case of the
end token, don't decrement ntokens if it was never incremented.
* tests/regression.at (Token number in precedence declaration):
Extend.
This commit is contained in:
Joel E. Denny
2011-05-01 21:53:35 -04:00
parent 441735026b
commit 9d6af15318
4 changed files with 32 additions and 5 deletions

View File

@@ -1,3 +1,15 @@
2011-05-01 Joel E. Denny <joeldenny@joeldenny.org>
Fix precedence for end token.
Since Bison 2.3b, which restored the ability of precedence
directives to assign user token numbers, doing so for user token
number 0 has produced an assertion failure.
* NEWS (2.5): Document fix.
* src/symtab.c (symbol_user_token_number_set): In the case of the
end token, don't decrement ntokens if it was never incremented.
* tests/regression.at (Token number in precedence declaration):
Extend.
2011-05-01 Joel E. Denny <joeldenny@joeldenny.org>
Prepare for 2.5 release.

10
NEWS
View File

@@ -343,6 +343,16 @@ Bison News
bison -Wnone gram.y
** Precedence directives can now assign token number 0:
Since Bison 2.3b, which restored the ability of precedence
directives to assign token numbers, doing so for token number 0 has
produced an assertion failure. For example:
%left END 0
This bug has been fixed.
* Changes in version 2.4.3 (2010-08-05):
** Bison now obeys -Werror and --warnings=error for warnings about

View File

@@ -368,10 +368,11 @@ symbol_user_token_number_set (symbol *sym, int user_token_number, location loc)
if (user_token_number == 0)
{
endtoken = sym;
endtoken->number = 0;
/* It is always mapped to 0, so it was already counted in
NTOKENS. */
if (endtoken->number != NUMBER_UNDEFINED)
--ntokens;
endtoken->number = 0;
}
}

View File

@@ -1205,12 +1205,15 @@ AT_DATA_GRAMMAR([input.y],
%}
%error-verbose
%right END 0
%left TK1 1 TK2 2 "tok alias" 3
%%
start: TK1 sr_conflict "tok alias" ;
start:
TK1 sr_conflict "tok alias"
| start %prec END
;
sr_conflict:
TK2
| TK2 "tok alias"
@@ -1240,7 +1243,8 @@ main (void)
]])
AT_BISON_CHECK([[-o input.c input.y]], [[0]],,
[[input.y:24.5-19: warning: rule useless in parser due to conflicts: sr_conflict: TK2 "tok alias"
[[input.y:23.5-19: warning: rule useless in parser due to conflicts: start: start
input.y:27.5-19: warning: rule useless in parser due to conflicts: sr_conflict: TK2 "tok alias"
]])
AT_COMPILE([[input]])
AT_PARSER_CHECK([[./input]])