[cfe-dev] libc++ on Mac OS X 10.6

[Douglas Gregor]

On Oct 10, 2011, at 1:45 AM, Jean-Daniel Dupas wrote:

> 
> Le 10 oct. 2011 à 10:17, Jonathan Sauer a écrit :
> 
>>>> When trying to use libc++ on a trunk clang on Mac OS X 10.6, I get:
>>>> 
>>>> /llvm-bin/bin/clang++ temp.cc -stdlib=libc++
>>>> clang: error: invalid deployment target for -stdlib=libc++ (requires Mac OS X 10.7 or later)
>>>> 
>>>> This used to work on 10.6. Was there a good reason for breaking this on 10.6, and is there any workaround?
>>>> 
>>>> I find this disappointing, as I had hoped the next release of clang, with libc++, would provide a good base-line C++0x compiler. However, I would really like not to require 10.7, as I know various people who do not intend to upgrade any time soon.
>>> 
>>> Sorry about that.  I've updated the instructions for building on 10.6.  Do:
>>> 
>>> $ export MACOSX_DEPLOYMENT_TARGET=10.6
>>> 
>>> prior to ./buildit
>> 
>> That seems to work for libc++. However, the problem persists when building an XCode project on 10.6:
>> 
>> | clang: error: invalid deployment target for -stdlib=libc++ (requires Mac OS X 10.7 or later)
>> 
>> When I change the build variable MACOSX_DEPLOYMENT_TARGET to 10.7, the project builds, but of course crashes on
>> startup.
>> 
>> The TOT from last week worked perfectly. Is there a non-political (i.e. not Apple wanting people to ditch 10.6)
>> reason for this change?
>> 
> 
> The commit you're looking for is r141374 ( https://llvm.org/viewvc/llvm-project?view=rev&sortby=log&revision=141374 )
> 
> Until you got an official response, you can at least look at the changes, and patch your local clang copy to be able to continue to use clang/libc++ on 10.6.


Thanks for tracking this down.

Apple only supports libc++ on Mac OS 10.7, so Apple's compiler checks for an appropriate deployment target when the user requests libc++. 

However, it doesn't make sense to have this restriction for the open-source compiler. We'll remove it.

	- Doug