When no ambiguity is possible, original symbol names may be used
as named references:
- if_stmt : 'if' cond_expr 'then' then_stmt ';'
+ if_stmt : "if" cond_expr "then" then_stmt ';'
{ $if_stmt = mk_if_stmt($cond_expr, $then_stmt); }
In the more common case, explicit names may be declared:
- stmt[res] : 'if' expr[cond] 'then' stmt[then] 'else' stmt[else] ';'
+ stmt[res] : "if" expr[cond] "then" stmt[then] "else" stmt[else] ';'
{ $res = mk_if_stmt($cond, $then, $else); }
Location information is also accessible using @name syntax. When
except that the manner in which Bison processes multiple definitions
for the same NAME differs. Most importantly, -F and --force-define
quietly override %define, but -D and --define do not. For further
- details, see the section "Bison Options" in the Bison manual.
+ details, see the section `Bison Options' in the Bison manual.
*** Variables renamed:
Similarly to the C parsers, the C++ parsers now define the YYRHSLOC
macro and use it in the default YYLLOC_DEFAULT. You are encouraged
- to use it. If, for instance, your location structure has "first"
- and "last" members, instead of
+ to use it. If, for instance, your location structure has `first'
+ and `last' members, instead of
# define YYLLOC_DEFAULT(Current, Rhs, N) \
do \
in order to detect a syntax error. Because no unexpected token or
expected tokens can then be reported, the verbose syntax error
message described above is suppressed, and the parser instead
- reports the simpler message, "syntax error". Previously, this
+ reports the simpler message, `syntax error'. Previously, this
suppression was sometimes erroneously triggered by %nonassoc when a
lookahead was actually required. Now verbose messages are
suppressed only when all previous lookaheads have already been
canonical LR. However, LAC is still experimental and is disabled
by default.
-** A location handling bug in the Java skeleton has been fixed.
+** Java skeleton fixes:
+
+*** A location handling bug has been fixed.
+
+*** The top element of each of the value stack and location stack is now
+ cleared when popped so that it can be garbage collected.
+
+*** Parser traces now print the top element of the stack.
+
+** -W/--warnings fixes:
+
+*** Bison now properly recognizes the `no-' versions of categories:
+
+ For example, given the following command line, Bison now enables all
+ warnings except warnings for incompatibilities with POSIX Yacc:
+
+ bison -Wall,no-yacc gram.y
+
+*** Bison now treats S/R and R/R conflicts like other warnings:
+
+ Previously, conflict reports were independent of Bison's normal
+ warning system. Now, Bison recognizes the warning categories
+ `conflicts-sr' and `conflicts-rr'. This change has important
+ consequences for the -W and --warnings command-line options. For
+ example:
+
+ bison -Wno-conflicts-sr gram.y # S/R conflicts not reported
+ bison -Wno-conflicts-rr gram.y # R/R conflicts not reported
+ bison -Wnone gram.y # no conflicts are reported
+ bison -Werror gram.y # any conflict is an error
+
+ However, as before, if the %expect or %expect-rr directive is
+ specified, an unexpected number of conflicts is an error, and an
+ expected number of conflicts is not reported, so -W and --warning
+ then have no effect on the conflict report.
+
+*** The `none' category no longer disables a preceding `error':
+
+ For example, for the following command line, Bison now reports
+ errors instead of warnings for incompatibilities with POSIX Yacc:
+
+ bison -Werror,none,yacc gram.y
+
+*** The `none' category now disables all Bison warnings.
+
+ Previously, the `none' category disabled only Bison warnings for
+ which there existed a specific -W/--warning category. However,
+ given the following command line, Bison is now guaranteed to
+ suppress all warnings:
+
+ bison -Wnone gram.y
* Changes in version 2.4.3 (2010-08-05):
projects / bison.git / blobdiff