This is the mail archive of the gdb@sourceware.org mailing list for the GDB project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: New GDB 7.5.x release sometime next week?


On Tuesday 27 November 2012 15:29:13 Joel Brobecker wrote:
> > how about this in libiberty/:
> > 2012-07-31  Mike Frysinger  <vapier@gentoo.org>
> > 
> > 	* md5.c (md5_finish_ctx): Declare swap_bytes.  Assign SWAP() output
> > 	to swap_bytes, and then call memcpy to move it to ctx->buffer.
> 
> As always, a quick explanation of what it fixes, and why it is
> important enough that it should be included in the release would help.
> Just from the ChangeLog entry alone, I am having a difficult time
> evaluating it.

Subject: [PATCH] libiberty/md5: fix strict alias warnings

Current libiberty md5 code triggers these warnings with gcc-4.7.1 for me:

libiberty/md5.c: In function 'md5_finish_ctx':
libiberty/md5.c:117:3: warning: dereferencing type-punned pointer will break 
strict-aliasing rules [-Wstrict-aliasing]
libiberty/md5.c:118:3: warning: dereferencing type-punned pointer will break 
strict-aliasing rules [-Wstrict-aliasing]

The change below fixes things for me.  The optimized output (-O2) is the same
before/after my change on x86_64-linux.  I imagine it'll be the same for most
targets.  It seems simpler than using a union on the md5_ctx buffer since these
are the only two locations in the code where this occurs.
-mike

Attachment: signature.asc
Description: This is a digitally signed message part.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]