[llvm] r238447 - AsmPrinter: Suppress warnings on GCC from r238362, NFC

[Duncan P. N. Exon Smith]

> On 2015-May-28, at 11:28, David Blaikie <dblaikie at gmail.com> wrote:
> 
>> 
>> 
>> On Thu, May 28, 2015 at 11:09 AM, Duncan P. N. Exon Smith <dexonsmith at apple.com> wrote:
>> Author: dexonsmith
>> Date: Thu May 28 13:09:13 2015
>> New Revision: 238447
>> 
>> URL: http://llvm.org/viewvc/llvm-project?rev=238447&view=rev
>> Log:
>> AsmPrinter: Suppress warnings on GCC from r238362, NFC
>> 
>> GCC seems to have some overzealous warnings about strict aliasing.
> 
> If the warning is wrong, can we just disable it rather than contorting the code to suppress it? (especially with the risk that warnings like this in GCC tend to be powered by their optimizer & thus might see through this & start warning again)

Sounds reasonable to me.  Although we seem to suppress it
elsewhere in our codebase (as Aaron pointed it) by casting
through `char*`, so we could just use that?  (I went this
way because Rafael had already confirmed it worked here, and,
for me, iterating on GCC means committing and watching bots.
Happy for someone to come up with something better or more
future-proof!)

>  
>> Rafael reports that this patch suppresses them on GCC 4.9, and I'm
>> hoping this will work for GCC 4.7 as well.  I'll watch [1] and iterate
>> if necessary.
>> 
>> [1]: http://bb.pgr.jp/builders/clang-3stage-x86_64-linux/builds/8597
>> 
>> Modified:
>>     llvm/trunk/include/llvm/CodeGen/DIE.h