llvm dev - Jan 2013 - [LLVMdev] Using C++'11 language features in LLVM itself

On Jan 8, 2013, at 8:09 PM, Peter Newman <peter at uformia.com>
wrote:
>>> One other specific problem with this is that (I'm told) MSVC
2010 doesn't support range-based for loops.  I don't think it is
reasonable to require windows users to be on MSVC 2012.  :-(
>> I suspect you're right about that, but I'd appreciate if some
MSVC
>> users would speak up here. We shouldn't hold back on using
range-based
>> for loops if all our MSVC users are happy to move to MSVC 2012
>> (assuming no problems with other platforms).
>> 
> For our works project, we are still stuck on MSVC 2005 and MSVC 2010
> (our software is a binary plugin to established products). Admittedly,
> we are still sitting on LLVM 2.8 with patches from 2.9 (2.9 wouldn't
> compile in MSVC 2010 for x64) . We want to move to current LLVM (not
> least for the NVPTX and AMDIL targets), but have not yet had the
> available man hours to do so.
Ok.  Unfortunately, I don't think it makes sense for the general community
to bend over backwards to support VC2005 anymore.  We're talking about LLVM
3.3 here (at the earliest), is there a strong reason you couldn't move to
VC2010 by whenever you move up to LLVM 3.3?

-Chris

On Wed, Jan 9, 2013 at 11:54 AM, Chris Lattner <clattner at apple.com>
wrote:
> On Jan 8, 2013, at 8:09 PM, Peter Newman <peter at uformia.com>
wrote:
>>>> One other specific problem with this is that (I'm told)
MSVC 2010 doesn't support range-based for loops.  I don't think it is
reasonable to require windows users to be on MSVC 2012.  :-(
>>> I suspect you're right about that, but I'd appreciate if
some MSVC
>>> users would speak up here. We shouldn't hold back on using
range-based
>>> for loops if all our MSVC users are happy to move to MSVC 2012
>>> (assuming no problems with other platforms).
>>>
>> For our works project, we are still stuck on MSVC 2005 and MSVC 2010
>> (our software is a binary plugin to established products). Admittedly,
>> we are still sitting on LLVM 2.8 with patches from 2.9 (2.9
wouldn't
>> compile in MSVC 2010 for x64) . We want to move to current LLVM (not
>> least for the NVPTX and AMDIL targets), but have not yet had the
>> available man hours to do so.
>
> Ok.  Unfortunately, I don't think it makes sense for the general
community to bend over backwards to support VC2005 anymore.  We're talking
about LLVM 3.3 here (at the earliest), is there a strong reason you couldn't
move to VC2010 by whenever you move up to LLVM 3.3?
>
> -Chris
LLVM has not been compatible with VS2005 for a long time.

And as a note to why you can be held back by external software on VS.
MSVC changes the C++ ABI with every release. If you have a 3rd party
product with no source access, or you need to dynamically link with a
specific version of that software, you must use the same VS version if
you use C++ in the ABI.

- Michael Spencer

>> Ok.  Unfortunately, I don't think it makes sense for the general
community to bend over backwards to support VC2005 anymore.  We're talking
about LLVM 3.3 here (at the earliest), is there a strong reason you couldn't
move to VC2010 by whenever you move up to LLVM 3.3?
>>
>> -Chris
> LLVM has not been compatible with VS2005 for a long time.
>
> And as a note to why you can be held back by external software on VS.
> MSVC changes the C++ ABI with every release. If you have a 3rd party
> product with no source access, or you need to dynamically link with a
> specific version of that software, you must use the same VS version if
> you use C++ in the ABI.
>
> - Michael Spencer
Oh I certainly don't expect anyone to keep supporting the ancient VS
2005 compiler. I'm just providing feedback on our usage, as asked. I
personally would think that VS2010 was reasonable to support for future
development though. Due to the C++ ABI changes (particularly their
runtime and memory management), as long as people want to binary
integrate with existing software, they can't upgrade their compiler as
they'd like.

Peter N