Re: gcc pragma pack on hpux

["John David Anglin" <dave at hiauly1 dot hia dot nrc dot ca>]

> I have a question about the HP-UX port of gcc, and from looking at the 
> gcc Contributors list it looks like you're the person to ask.  I'm 
> working on porting some software (winelib) that makes heavy use of 
> #pragma pack, and gcc doesn't support this pragma on HP-UX.  I was 
> hoping you could tell me why it is disabled.
> 
> I tried adding the HANDLE_PRAGMA_PACK define to gcc's config files and 
> it looks like #pragma pack started working correctly (I haven't run the 
> regression tests yet to confirm it).

I don't know.  It hasn't come up in the period that I have been
involved in GCC.

> If necessary, I think I can use __attribute__((packed,aligned(x))) to 
> work around this, but it needs to be applied on a structure-by-structure 
> basis.  The software I'm porting has about 10k lines surrounded by 
> pragma pack directives, so converting it to use attributes would be very 
> tedious.
> 
> Do you know if turning on these options will break anything?  Is there 
> any chance future releases of gcc will have this enabled by default?

The maximum alignment available for bss/common variables is 8 bytes
with the 32-bit SOM linker.  That's the only restriction that I'm
aware of,  Thus, it may be ok to define HANDLE_PRAGMA_PACK_PUSH_POP
in the file hpux.h.

Dave
-- 
J. David Anglin                                  dave.anglin@nrc-cnrc.gc.ca
National Research Council of Canada              (613) 990-0752 (FAX: 952-6602)