Version 2.5.

* NEWS (2.5): Set date.

ChangeLog

@@ -1,3 +1,43 @@
+2011-05-14  Joel E. Denny  <[email protected]>
+
+	Version 2.5.
+	* NEWS (2.5): Set date.
+
+2011-05-14  Joel E. Denny  <[email protected]>
+
+	Don't use IF_LINT in Bison sources.
+	It creates unnecessary differences between the sources that Bison
+	maintainers build and test (given that maintainers normally
+	configure with --enable-gcc-warnings) and the sources that Bison
+	users build.  Instead, use PACIFY_CC, which doesn't.  This change
+	fixes compiler warnings reported by Tys Lefering at
+	<http://lists.gnu.org/archive/html/bison-patches/2011-05/msg00004.html>.
+	* configure.ac: Don't AC_DEFINE lint regardless of the configure
+	options.  This change affects imported gnulib sources, where
+	IF_LINT still appears and depends on lint.
+	* src/scan-gram.l, src/scan-skel.l: Replace uses of IF_LINT with
+	PACIFY_CC.
+	* src/system.h (IF_LINT): Remove cpp macro.
+	(PACIFY_CC): New cpp macro.
+
+2011-05-01  Joel E. Denny  <[email protected]>
+
+	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  <[email protected]>
+
+	Prepare for 2.5 release.
+	* NEWS (2.5_rc1): Rename back to...
+	(2.5): ... this, and unset date.
+
 2011-05-01  Joel E. Denny  <[email protected]>
 
 	Version 2.5_rc1.

NEWS

@@ -1,7 +1,7 @@
 Bison News
 ----------
 
-* Changes in version 2.5_rc1 (2011-05-01):
+* Changes in version 2.5 (2011-05-14):
 
 ** Grammar symbol names can now contain non-initial dashes:
 
@@ -334,7 +334,7 @@ Bison News
 
     bison -Werror,none,yacc gram.y
 
-*** The `none' category now disables all Bison warnings.
+*** 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,
@@ -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

configure.ac

@@ -84,7 +84,6 @@ if test "${enableval}" = yes; then
   WARN_CFLAGS_TEST="$WARN_CFLAGS $WARN_CFLAGS_TEST"
   AC_SUBST([WARN_CXXFLAGS_TEST])
   AC_SUBST([WARN_CFLAGS_TEST])
-  AC_DEFINE([lint], 1, [Define to 1 if the compiler is checking for lint.])
 fi
 
 BISON_TEST_FOR_WORKING_C_COMPILER

src/scan-gram.l

@@ -120,13 +120,13 @@ splice	 (\\[ \f\t\v]*\n)*
 %%
 %{
   /* Nesting level of the current code in braces.  */
-  int braces_level IF_LINT (= 0);
+  int braces_level PACIFY_CC (= 0);
 
   /* Parent context state, when applicable.  */
-  int context_state IF_LINT (= 0);
+  int context_state PACIFY_CC (= 0);
 
   /* Location of most recent identifier, when applicable.  */
-  location id_loc IF_LINT (= empty_location);
+  location id_loc PACIFY_CC (= empty_location);
 
   /* Where containing code started, when applicable.  Its initial
      value is relevant only when yylex is invoked in the SC_EPILOGUE
@@ -135,7 +135,7 @@ splice	 (\\[ \f\t\v]*\n)*
 
   /* Where containing comment or string or character literal started,
      when applicable.  */
-  boundary token_start IF_LINT (= scanner_cursor);
+  boundary token_start PACIFY_CC (= scanner_cursor);
 %}
 
 

src/scan-skel.l

@@ -58,7 +58,7 @@ static void fail_for_invalid_at (char const *at);
 %%
 
 %{
-  int out_lineno IF_LINT (= 0);
+  int out_lineno PACIFY_CC (= 0);
   char *outname = NULL;
 
   /* Currently, only the @warn, @complain, @fatal, @warn_at, @complain_at, and

src/symtab.c

@@ -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.  */
-      --ntokens;
+      if (endtoken->number != NUMBER_UNDEFINED)
+        --ntokens;
+      endtoken->number = 0;
     }
 }
 

src/system.h

@@ -66,13 +66,19 @@ typedef size_t uintptr_t;
 | GCC extensions.  |
 `-----------------*/
 
-/* Use this to suppress gcc's `...may be used before initialized'
-   warnings.  */
-#ifdef lint
-# define IF_LINT(Code) Code
-#else
-# define IF_LINT(Code) /* empty */
-#endif
+/* Use PACIFY_CC to indicate that Code is unimportant to the logic of Bison
+   but that it is necessary for suppressing compiler warnings.  For example,
+   Code might be a variable initializer that's always overwritten before the
+   variable is used.
+
+   PACIFY_CC is intended to be useful only as a comment as it does not alter
+   Code.  It is tempting to redefine PACIFY_CC so that it will suppress Code
+   when configuring without --enable-gcc-warnings.  However, that would mean
+   that, for maintainers, Bison would compile with potentially less warnings
+   and safer logic than it would for users.  Due to the overhead of M4,
+   suppressing Code is unlikely to offer any significant improvement in
+   Bison's performance anyway.  */
+#define PACIFY_CC(Code) Code
 
 #ifndef __attribute__
 /* This feature is available in gcc versions 2.5 and later.  */

tests/regression.at

@@ -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]])