RE: __attribute__((__unused__)) problem

[victor khomenko]

Dear Akim,

Many thanks for a quick reaction!

I'll try to check the tarball later today, though it will require some time (I 
need to figure out how to build it on a windows machine).

Also, I did have a few warnings in the bison-generated parsers, and will report 
those too.

Best regards,
Victor.


> -----Original Message-----
> From: Akim Demaille [mailto:address@hidden
> Sent: Monday, April 08, 2013 10:59 AM
> To: victor khomenko
> Cc: 'address@hidden'
> Subject: Re: __attribute__((__unused__)) problem
> 
> 
> Le 8 avr. 2013 à 10:28, Akim Demaille <address@hidden> a écrit :
> 
> > Hi Victor,
> >
> > You are right, this is a serious issue :(  I will prepare a 2.7.1
> > asap.  Could you please help me making sure it works properly with
> > Microsoft compilers?  Actually, it would be nice if you could also
> > help me kill some compiler warnings.   Please, have a look at the
> > following message.
> >
> > http://lists.gnu.org/archive/html/bug-bison/2013-03/msg00003.html
> 
> I will install this is {maint}.  Could you please confirm
> that the following tarball addresses your issue?  Thanks in
> advance!
> 
> http://www.lrde.epita.fr/~akim/download/bison-2.7.7-a565f.tar.gz
> 
> commit 80a2826e69b201f9a64c3f18825afe879472efb4
> Author: Akim Demaille <address@hidden>
> Date:   Mon Apr 8 10:39:48 2013 +0200
> 
>     yacc.c: do not use __attribute__ unprotected
> 
>     Reported by Victor Khomenko.
>     http://lists.gnu.org/archive/html/bug-bison/2013-04/msg00001.html
> 
>     * data/glr.c (YYUSE, __attribute__): Fuse their definition into...
>     * data/c.m4 (b4_attribute_define): this new macro.
>     * data/yacc.c, data/glr.c: Use it.
> 
> diff --git a/NEWS b/NEWS
> index 8da9cf9..b499cc1 100644
> --- a/NEWS
> +++ b/NEWS
> @@ -2,6 +2,11 @@ GNU Bison NEWS
> 
>  * Noteworthy changes in release ?.? (????-??-??) [?]
> 
> +** Bug fixes
> +
> +*** Fix compiler attribute portability (yacc.c)
> +
> +  With locations enabled, __attribute__ was used unprotected.
> 
>  * Noteworthy changes in release 2.7 (2012-12-12) [stable]
> 
> diff --git a/THANKS b/THANKS
> index ed978d3..9b24974 100644
> --- a/THANKS
> +++ b/THANKS
> @@ -121,6 +121,7 @@ Tom Tromey                address@hidden
>  Tommy Nordgren            address@hidden
>  Troy A. Johnson           address@hidden
>  Tys Lefering              address@hidden
> +Victor Khomenko           address@hidden
>  Vin Shelton               address@hidden
>  W.C.A. Wijngaards         address@hidden
>  Wayne Green               address@hidden
> diff --git a/data/c.m4 b/data/c.m4
> index dc3d303..a1dc2c5 100644
> --- a/data/c.m4
> +++ b/data/c.m4
> @@ -187,9 +187,29 @@ m4_define([b4_table_value_equals],
>         [(!!(($2) == ($3)))])])
> 
> 
> -## ---------##
> -## Values.  ##
> -## ---------##
> +## ----------------- ##
> +## Compiler issues.  ##
> +## ----------------- ##
> +
> +# b4_attribute_define
> +# -------------------
> +# Provide portability for __attribute__.
> +m4_define([b4_attribute_define],
> +[#ifndef __attribute__
> +/* This feature is available in gcc versions 2.5 and later.  */
> +# if (! defined __GNUC__ || __GNUC__ < 2 \
> +      || (__GNUC__ == 2 && __GNUC_MINOR__ < 5))
> +#  define __attribute__(Spec) /* empty */
> +# endif
> +#endif
> +
> +/* Suppress unused-variable warnings by "using" E.  */
> +#if ! defined lint || defined __GNUC__
> +# define YYUSE(E) ((void) (E))
> +#else
> +# define YYUSE(E) /* empty */
> +#endif
> +])
> 
> 
>  # b4_null_define
> @@ -405,7 +425,7 @@ m4_define([b4_c_arg],
>  ## ----------- ##
> 
>  # b4_sync_start(LINE, FILE)
> -# -----------------------
> +# -------------------------
>  m4_define([b4_sync_start], [[#]line $1 $2])
> 
> 
> diff --git a/data/glr.c b/data/glr.c
> index 02a76c2..958b040 100644
> --- a/data/glr.c
> +++ b/data/glr.c
> @@ -246,13 +246,6 @@ b4_percent_code_get[]dnl
>  # endif
>  #endif
> 
> -/* Suppress unused-variable warnings by "using" E.  */
> -#if ! defined lint || defined __GNUC__
> -# define YYUSE(E) ((void) (E))
> -#else
> -# define YYUSE(E) /* empty */
> -#endif
> -
>  /* Identity function, used to suppress warnings about constant conditions.
> */
>  #ifndef lint
>  # define YYID(N) (N)
> @@ -291,17 +284,7 @@ b4_percent_code_get[]dnl
>  # define YYLONGJMP(Env, Val) (longjmp (Env, Val), YYASSERT (0))
>  #endif
> 
> -/*-----------------.
> -| GCC extensions.  |
> -`-----------------*/
> -
> -#ifndef __attribute__
> -/* This feature is available in gcc versions 2.5 and later.  */
> -# if (! defined __GNUC__ || __GNUC__ < 2 \
> -      || (__GNUC__ == 2 && __GNUC_MINOR__ < 5))
> -#  define __attribute__(Spec) /* empty */
> -# endif
> -#endif
> +]b4_attribute_define[
> 
>  #ifndef YYASSERT
>  # define YYASSERT(Condition) ((void) ((Condition) || (abort (), 0)))
> diff --git a/data/yacc.c b/data/yacc.c
> index b34549f..abc949b 100644
> --- a/data/yacc.c
> +++ b/data/yacc.c
> @@ -447,12 +447,7 @@ typedef short int yytype_int16;
>  # endif
>  #endif
> 
> -/* Suppress unused-variable warnings by "using" E.  */
> -#if ! defined lint || defined __GNUC__
> -# define YYUSE(E) ((void) (E))
> -#else
> -# define YYUSE(E) /* empty */
> -#endif
> +]b4_attribute_define[
> 
>  /* Identity function, used to suppress warnings about constant conditions.
> */
>  #ifndef lint