svn commit: r346492 - projects/runtime-coverage-v2/lib/libclang_rt

[Enji Cooper]

> On Apr 22, 2019, at 9:22 AM, John Baldwin <jhb at FreeBSD.org> wrote:
> 
> On 4/21/19 12:26 PM, Enji Cooper wrote:
>> Author: ngie
>> Date: Sun Apr 21 19:26:40 2019
>> New Revision: 346492
>> URL: https://svnweb.freebsd.org/changeset/base/346492
>> 
>> Log:
>>  Build libclang_rt/profile on all clang-supported architectures
>> 
>>  There's no reason why a special case needs to be added specifically for amd64,
>>  arm, and i386, as the code is written in machine architecture agnostic C/C++.
>> 
>>  There might be compilation/link time issues, but we'll find out soon.
> 
> For a sanitizer to be useful, you need to make sure clang's FreeBSD driver
> will actually use it.  clang has builtin knowledge about which sanitizers
> work on which architectures.  Just building the library alone doesn't enable
> it unless you also check the driver in clang.  I haven't looked to see what
> conditions clang places on the profile case, but I am familiar with this
> from working on ASAN support for mips.

	Totally agree. What you’re referring to deals more with ASAN/MSAN/TSAN, not profile, which is gcov-compatible profiling where counters are incremented for lines hit and used in analysis tools like coverity/lcov. gcov can be implemented in machine architecture independent code.
Cheers!
-Enji