[LLVMdev] CMake, compiler-rt, and MacOS

[Alexey Samsonov]

On Fri, Feb 8, 2013 at 1:08 AM, Erik Verbruggen <erik.verbruggen at me.com>wrote:

>
> On Feb 5, 2013, at 15:14, Alexey Samsonov <samsonov at google.com> wrote:
>
>
> On Tue, Feb 5, 2013 at 12:38 PM, Kostya Serebryany <kcc at google.com> wrote:
>
>> +samsonov, glider
>>
>>
>> On Tue, Feb 5, 2013 at 12:16 PM, Chandler Carruth <chandlerc at google.com>wrote:
>>
>>> On Mon, Feb 4, 2013 at 6:21 AM, Erik Verbruggen <erik.verbruggen at me.com>wrote:
>>>
>>>> Hi Chandler,
>>>>
>>>> If I remember correctly, you are the de-facto maintainer for the
>>>> CMake-built-mainainer, so..:
>>>>
>>>
>>> Sure, but I'm often busy. You're better off using the development
>>> mailing list for questions such as this, and I've moved the conversation
>>> there.
>>>
>>>
>>>> I have a problem compiling compiler-rt on MacOS with libc++. For this
>>>> to work, the flag -mmacosx-version-min=10.7 is required, so I use:
>>>> CMAKE_CXX_FLAGS:STRING=-mmacosx-version-min=10.7 -stdlib=libc++
>>>>
>>>> However, around line 140, the CMakeLists.txt of compiler-rt contains:
>>>> if(APPLE)
>>>>   list(APPEND SANITIZER_COMMON_CFLAGS -mmacosx-version-min=10.5)
>>>> endif()
>>>>
>>>> Now, when building with clang, the minimal minimal version is used, so
>>>> 10.5, which results in a compiler error complaining that the minimal
>>>> version should be 10.7.
>>>>
>>>> My question: could you please add some CMake logic to the compiler-rt
>>>> CMakeLists.txt to check if there is already a macosx-version-min flag set,
>>>> or to not include the flag if -stdlib=libc++ is set?
>>>>
>>>
> Hi Erik,
> IIRC, using -stdlib=libc++ on Mac should also require presence of flag
> -mmacosx-version-min? If that's the case, then probably we can put the logic
> of determining the set of flags required for libc++ into CMake build rules
> and use CMake variable like COMPILER_RT_USES_LIBCXX. Does the attached
> patch solve a problem for you? If you're building LLVM/Clang tree,
> however, we may want to hoist this to smth. like LLVM_USES_LIBCXX.
>
>
> Yes, that works, when I (manually) set the COMPILER_RT_USES_LIBCXX flag. I
> was wondering if that flag could actually be set when detecting the
> -stdlib=libc++ flag...
>

r174699 should do this.


>
> -- Erik.
>
>


-- 
Alexey Samsonov, MSK
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20130208/adb3bd6b/attachment.html>