gcc 2.95/C: flexible array member as error, breaks ISO C

[Fieldhouse, Dirk]

On 14 February 2000 22:43, Martin v. Loewis
[ mailto:martin@loewis.home.cs.tu-berlin.de ] wrote:
 
> 
> DF> This seems to be a bug in gcc's ISO/ANSI C compliance.
> 
> Thanks for your bug report. I believe this is a known bug, since this
> feature is new in C 99, right? Please have a look at
> 
> http://gcc.gnu.org/c9xstatus.html

OK, that's just right. I thought this feature seemed novel.

However your proposed work-around is specifically prohibited at ISO 6.7.5.2
(constant array dimension must be > 0). I went for 

#ifdef __GNUC__
 	ClnpT_MacIf		mac_intf_tbl[1];
#else
 	ClnpT_MacIf		mac_intf_tbl[];
#endif

This is fine except that an array bounds check might fail.

It looks as if the C99 array handling needs some work. I wish I had time to
help.

thanks
/df

> Flexible array members are currently missing in gcc; as a work-around,
> you can use array of zero length:
> 
> typedef struct {
> 	int*			srv_status_table;
> 	int*			srv_pkid_table;
> 	int			num_busy_srv;
> 	double			q_cum_pks;
> 	double			q_cum_bits;
> 	List*			in_queue[15];
> 	int 			num_intf;
> 	} AcT_Clnp_Data;
> 
> > Please contact me for any further details.
> 
> Thanks; unless I misinterpreted your report, we don't need more
> details at the moment. Of course, if you are willing to provide a
> patch to add the missing feature - that would be much
> appreciated. Please send them to gcc-patches@gcc.gnu.org.
> 
> Regards,
> Martin
>