[cfe-dev] clang ToT doesn't build on macOS 10.10 anymore...?

[Sean McBride via cfe-dev]

CC'ing ahatanak and efriedma

So I bisected where building on macOS 10.10 broke, and found at least 2 commits that introduced errors:

-------------------------------
r313929 | ahatanak | 2017-09-21 18:16:50 -0400 (Thu, 21 Sep 2017)

/llvm/llvm/projects/compiler-rt/lib/tsan/rtl/tsan_libdispatch_mac.cc:229:1: error: unknown type name 'DISPATCH_NOESCAPE'
DISPATCH_INTERCEPT_SYNC_B(dispatch_sync, false)
^
-------------------------------

-------------------------------
r314851 | efriedma | 2017-10-03 17:25:07 -0400 (Tue, 03 Oct 2017)

/llvm/llvm/projects/compiler-rt/lib/builtins/adddf3.c:28:53: error: alias unsupported on this file format
AEABI_RTABI double __aeabi_dadd(double a, double b) COMPILER_RT_ALIAS(__adddf3);
                                                    ^
-------------------------------


On Wed, 7 Feb 2018 12:23:16 +0100, Hans Wennborg said:

>I just ran into the same thing :-/
>
>On Fri, Jan 26, 2018 at 11:22 PM, Sean McBride via cfe-dev
><cfe-dev at lists.llvm.org> wrote:
>> Hi all,
>>
>> I just tried updating my clang build on a few machines, and it built
>fine on 10.11, but on a macOS 10.10 with AppleClang 7.0.2.7000181 I get this:
>>
>> /Users/builder/llvm/llvm/projects/compiler-rt/lib/builtins/adddf3.c:
>28:53: error: alias unsupported on this file format
>> AEABI_RTABI double __aeabi_dadd(double a, double b)
>COMPILER_RT_ALIAS(__adddf3);
>>                                                     ^
>> /Users/builder/llvm/llvm/projects/compiler-rt/lib/builtins/int_lib.h:
>29:36: note: expanded from macro 'COMPILER_RT_ALIAS'
>> #define COMPILER_RT_ALIAS(aliasee) _Pragma("GCC error(\"alias
>unsupported on this file format\")")
>>                                    ^
>> <scratch space>:89:6: note: expanded from here
>>  GCC error("alias unsupported on this file format")
>>      ^
>>
>> Should this build?  Is 10.10 supported?