Re: GCC4 status.

[Charles Wilson <cygwin@cwilson.fastmail.fm>]

Dave Korn wrote:
> Corinna Vinschen wrote:
>> #2)
>>
>>   /usr/lib/gcc/i686-pc-cygwin/4.3.2/../../../../i686-pc-cygwin/bin/ld:
>>   warning: auto-importing has been activated without --enable-auto-import
>>   specified on the command line.
>>   This should work unless it involves constant data structures referencing
>>   symbols from auto-imported DLLs.
>>
>>   *Sob*  Yes, officer, I confess everything!  But *please* don't tell
>>   me this every time I dare to link an application.
>>
>> Is there any chance to get rid of this really useless stuff upstream?
> 
>   I don't know.  We could turn on auto import globally but that will pessimize
> a whole bunch of stuff that needn't be affected.  We could discard the warning
> altogether but then people would get silent failures.

It's already on by default. The variable
link_info.pei386_auto_import
is currently initialized to -1, which means "Do it, but complain".

The only thing changing that initialization to "1" would do, would be to
stop complaining.

You already have to use explicitly --disable-auto-import to turn it off.

>  What would be best of all would be to only issue the warning if a const data
> structure reference of the kind mentioned actually occurs.  I haven't looked
> to see if that's possible to detect yet, but it would be a nice fix for
> upstream ld.

Actually, with Kai's recent changes, IF we
 (1) modified cygwin's src/winsup/cygwin/lib/pseudo-reloc.c file to
support -v2 psuedo-relocs
 (2) EVENTUALLY, after much testing, changed cygwin-ld's default reloc
mode from (current: not enabled; CVS ld: v1 enabled) to v2 enabled, THEN

we can have const structure references (and "complex" data type
references) that can be updated without error.

I think.

See:
http://cygwin.com/ml/cygwin-developers/2009-01/msg00009.html
and following thread, as well as embedded links in the referenced message.

> As a workaround, the sources could always be fixed.  Inconsistent
> declarations *is* a correctness issue, after all, and it's usually trivial to
> add an item to LDFLAGS.
> 
>   Also, perhaps as a half-way compromise measure, auto import could be enabled
> in the GCC specs for just C++/ObjC++/Java.  I don't know what's for the best
> yet, does anyone else have any suggestions?

See previous message.

--
Chuck