Commit Graph

331 Commits

Author SHA1 Message Date
Evgenii Stepanov a1817996fa Fix lld detection in standalone compiler-rt.
Summary:
Right now all hwasan tests on Android are silently disabled because they
require "has_lld" and standalone compiler-rt can not (and AFAIK was
never able to) set it.

Reviewers: pcc

Subscribers: dberris, mgorny, #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D69405
2019-10-24 14:46:10 -07:00
Evgenii Stepanov 70316d3174 Revert "Fix lld detection in standalone compiler-rt."
Breaks sanitizer-android buildbot.

This reverts commit d56203201f.
2019-10-22 13:36:06 -07:00
Evgeniy Stepanov d56203201f Fix lld detection in standalone compiler-rt.
Summary:
Right now all hwasan tests on Android are silently disabled because they
require "has_lld" and standalone compiler-rt can not (and AFAIK was
never able to) set it.

Reviewers: pcc, dyung

Subscribers: dberris, mgorny, #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D69196

llvm-svn: 375472
2019-10-21 23:59:45 +00:00
Vitaly Buka acd8499028 [compiler-rt] Don't use libcxx if it's not enabled by LLVM_ENABLE_PROJECTS
This fixes sanitizer-x86_64-linux-fuzzer which switched to new layout and not it
can't link as libcxx is always there.
We should support and tests libcxx but still it was unexpected that libfuzzer
ignored LLVM_ENABLE_PROJECTS_USED.

llvm-svn: 370153
2019-08-28 02:41:14 +00:00
Mitch Phillips ae56e593b9 Add GWP-ASan fuzz target to compiler-rt/tools.
Summary:
@eugenis to approve addition of //compiler-rt/tools.
@pree-jackie please confirm that this WFY.

D66494 introduced the GWP-ASan stack_trace_compressor_fuzzer. Building fuzz
targets in compiler-rt is a new affair, and has some challenges:
- If the host compiler doesn't have compiler-rt, the -fsanitize=fuzzer may not
  be able to link against `libclang_rt.fuzzer*`.
- Things in compiler-rt generally aren't built when you want to build with
  sanitizers using `-DLLVM_USE_SANITIZER`. This tricky to work around, so
  we create the new tools directory so that we can build fuzz targets with
  sanitizers. This has the added bonus of fixing the problem above as well, as
  we can now just guard the fuzz target build to only be done with
  `-DLLVM_USE_SANITIZE_COVERAGE=On`.

Reviewers: eugenis, pree-jackie

Reviewed By: eugenis, pree-jackie

Subscribers: dberris, mgorny, #sanitizers, llvm-commits, eugenis, pree-jackie, lebedev.ri, vitalybuka, morehouse

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D66776

llvm-svn: 370094
2019-08-27 18:28:07 +00:00
Ulrich Weigand f7489141be [Sanitizer] Disable -Wframe-larger-than on SystemZ
SystemZ builds show -Wframe-larger-than warnings in two functions:
 'sanitizer::SuspendedThreadsListLinux::GetRegistersAndSP'
 'sanitizer::SizeClassAllocator32<__sanitizer::AP32>::PopulateFreeList'

In both cases, the frame size looks correct; each of the functions has
a large local variable that brings the frame size close to the limit
even on x86, and the extra 160 bytes of the default register save areas
on SystemZ pushes it over the limit.

PowerPC and MIPS already disable this warning; do the same on SystemZ.

Differential Revision: https://reviews.llvm.org/D66021

llvm-svn: 369543
2019-08-21 15:53:08 +00:00
Jonas Devlieghere 4d474e078a [CMake] Check for C++14 instead of C++11
Now that LLVM moved to C++14, `COMPILER_RT_HAS_STD_CXX11_FLAG` should
become `COMPILER_RT_HAS_STD_CXX14_FLAG`.

I ran into this issue when replacing llvm::make_unique with
std::make_unique in an X-ray unit test. We are correctly passing
`-std=c++14`, but this got overwritten further down the invocation by
the compiler-rt flags. Given that this unit test is using LLVM headers,
this is bound to break sooner than later, regardless of my change.

Differential revision: https://reviews.llvm.org/D66271

llvm-svn: 368960
2019-08-15 04:42:15 +00:00
Nico Weber 673dc3d4a0 compiler-rt: Rename cc files below test/asan to cpp
See r367803 and similar other changes.

llvm-svn: 367887
2019-08-05 16:48:12 +00:00
Reid Kleckner c41b58fd40 Remove cmake checks for MSVC 1900 / VS 2013
Our minimum Visual C++ version is 19.10 from Visual Studio 2017.

llvm-svn: 367362
2019-07-30 22:49:11 +00:00
Jonas Devlieghere a5359b1b07 [CMake] Don't set Python_ADDITIONAL_VERSIONS
Until recently, Python_ADDITIONAL_VERSIONS was used to limit LLVM's
Python support to 2.7. Now that both LLVM and LLDB both support Python
3, there's no longer a need to put an arbitrary limit on this.

However, instead of removing the variable, r365692 expanded the list,
which has the (presumably unintentional) side-effect of expression
preference for Python 3.

Instead, as Michal proposed in the original code review, we should just
not set the list at all, and let CMake pick whatever Python interpreter
you have in your path.

This patch removes the Python_ADDITIONAL_VERSIONS variable in llvm,
clang and lld. I've also updated the docs with the default behavior and
how to force a different Python version to be used.

Differential revision: https://reviews.llvm.org/D64894

llvm-svn: 366447
2019-07-18 15:17:42 +00:00
Ulrich Weigand 45b10d2da5 [compiler-rt][SystemZ] Work around ASAN failures via -fno-partial-inlining
Since updating the SystemZ LLVM build bot system to Ubuntu 18.04, all bots
are red due to two ASAN failures.  It turns out these are triggered due to
building the ASAN support libraries, in particular the interceptor routines
using GCC 7.  Specifically, at least on our platform, this compiler decides
to "partially inline" some of those interceptors, creating intermediate
stub routines like "__interceptor_recvfrom.part.321".  These will show up
in the backtraces at interception points, causing testsuite failures.

As a workaround to get the build bots green again, this patch adds the
-fno-partial-inlining command line option when building the common
sanitizer support libraries on s390x, if that option is supported by
the compiler.

llvm-svn: 363679
2019-06-18 13:26:27 +00:00
Petr Hosek d2d6c17760 [builtins] Use libtool for builtins when building for Apple platform
compiler-rt already uses libtool instead of ar when building for
Apple platform, but that's not being used when builtins are being
built separately e.g. as part of the runtimes build. This change
extracts the logic setting up libtool into a separate file and uses
it from both the compiler-rt and standalone builtins build.

Differential Revision: https://reviews.llvm.org/D62820

llvm-svn: 362466
2019-06-04 02:38:15 +00:00
Shoaib Meenai 363079fe73 [compiler-rt] Fix cmake warnings
- Fix cmake BOOL misspellings
 - Set cmake policy for CMP0075 to NEW

As requested by smeenai I've compared CMAkeCache.txt in master with and
without this patch and the only changes are to the variable types I fixed:

     $ diff build-b1-master/CMakeCache.txt build-b1-compiler-rt-fix-cmake-warnings/CMakeCache.txt
     503c503
     < COMPILER_RT_BAREMETAL_BUILD:STRING=OFF
     ---
     > COMPILER_RT_BAREMETAL_BUILD:BOOL=OFF
     550c550
     < COMPILER_RT_HWASAN_WITH_INTERCEPTORS:STRING=ON
     ---
     > COMPILER_RT_HWASAN_WITH_INTERCEPTORS:BOOL=ON

Patch by Wink Saville <wink@saville.com>.

Differential Revision: https://reviews.llvm.org/D61203

llvm-svn: 361866
2019-05-28 19:09:17 +00:00
Julian Lettner e24ed10aac [NFC][TSan][libdispatch] Tiny CMake file cleanup
llvm-svn: 360453
2019-05-10 18:37:30 +00:00
Petr Hosek 999bb5ac27 Reland "[compiler-rt] Simple crtbegin.o and crtend.o implementation"
Clang relies on existence of certain symbols that are normally
provided by crtbegin.o/crtend.o. However, LLVM does not currently
provide implementation of these files, instead relying on either
libgcc or implementations provided as part of the system.

This change provides an initial implementation of crtbegin.o/crtend.o
that can be used on system that don't provide crtbegin.o/crtend.o as
part of their C library.

Differential Revision: https://reviews.llvm.org/D28791

llvm-svn: 359591
2019-04-30 18:13:22 +00:00
Petr Hosek 9300f60c8c Revert "[compiler-rt] Simple crtbegin.o and crtend.o implementation"
This reverts commit r359576 since it's failing on Windows bots.

llvm-svn: 359579
2019-04-30 17:32:05 +00:00
Petr Hosek c8be6e670e [compiler-rt] Simple crtbegin.o and crtend.o implementation
Clang relies on existence of certain symbols that are normally
provided by crtbegin.o/crtend.o. However, LLVM does not currently
provide implementation of these files, instead relying on either
libgcc or implementations provided as part of the system.

This change provides an initial implementation of crtbegin.o/crtend.o
that can be used on system that don't provide crtbegin.o/crtend.o as
part of their C library.

Differential Revision: https://reviews.llvm.org/D28791

llvm-svn: 359576
2019-04-30 17:21:13 +00:00
Julian Lettner f7461b8c5f [TSan][libdispatch] Specify libdispatch header dir for lit tests
Specify libdispatch header dir (include path) for lit tests. This is the
last missing piece in order to run the libdispatch tests on Linux even
when libdispatch is installed in a custom path instead of a default
(system) location.

llvm-svn: 357707
2019-04-04 17:25:43 +00:00
Julian Lettner b8c6effacf [NFC][TSan][libdispatch] Better CMake variable names
llvm-svn: 357664
2019-04-04 01:10:07 +00:00
Julian Lettner 15f0057e66 [TSan][libdispatch] Add Cmake option for libdispatch install path
llvm-svn: 357657
2019-04-04 00:28:09 +00:00
Julian Lettner 9ca4ff2666 [TSan][libdispatch] We don't require any setup on Darwin
llvm-svn: 357519
2019-04-02 20:04:32 +00:00
Julian Lettner 764c2165e8 [TSan][libdispatch] Enable linking and running of tests on Linux
When COMPILER_RT_INTERCEPT_LIBDISPATCH is ON the TSan runtime library
now has a dependency on the blocks runtime and libdispatch. Make sure we
set all the required linking options.

Also add cmake options for specifying additional library paths to
instruct the linker where to search for libdispatch and the blocks
runtime. This allows us to build TSan runtime with libdispatch support
without installing those libraries into default linker library paths.

`CMAKE_TRY_COMPILE_TARGET_TYPE=STATIC_LIBRARY` is necessary to avoid
aborting the build due to failing the link step in CMake's
check_c_compiler test.

Reviewed By: dvyukov, kubamracek

Differential Revision: https://reviews.llvm.org/D59334

llvm-svn: 356281
2019-03-15 17:52:27 +00:00
Julian Lettner 98a00defe1 [Sanitizer] Add 'dispatch' feature to be used in compiler-rt tests
Reviewed By: dvyukov

Differential Revision: https://reviews.llvm.org/D59037

llvm-svn: 355617
2019-03-07 18:15:23 +00:00
Julian Lettner 96ef52ccf0 [tsan] Support interception of libdispatch on Linux
This is a new attempt for bringing TSan libdispatch support to Linux.
The main issue with the last patch (https://reviews.llvm.org/D53171) was
that we want to avoid building a separate library.

The updated plan is as follows:
1) Hide libdispatch support behind a flag: true on Darwin, false
   elsewhere. If flag is specified, assume that libdispatch header and
   -flbocks is available for building. This way we can directly include
   the libdispatch header and rely on blocks runtime for our
   implementation.
2) Optionally/weakly intercept libdispatch API functions.

This patch accomplishes 1). It compiles (without the flag enabled) on
Linux. Follow-up patches will provide 2) and enabling of tests on Linux.

Reviewed By: dvyukov

Differential Revision: https://reviews.llvm.org/D58935

llvm-svn: 355538
2019-03-06 19:25:09 +00:00
Martin Storsjo ad596c8d8c [CMake] Don't use llvm_replace_compiler_option
Building compiler-rt standalone outside of the main llvm
tree is supported, and in this case, the llvm cmake modules
are unavailable. (And even if they are available, it requires
including LLVMProcessSources.cmake, which currently isn't
included.)

This fixes building compiler-rt standalone with MSVC/clang-cl.

Differential Revision: https://reviews.llvm.org/D58767

llvm-svn: 355237
2019-03-01 22:30:17 +00:00
Evgeniy Stepanov 9ca1755f76 [sanitizer] Build everything whereever possible with -z text.
Reviewers: pcc, phosek

Subscribers: mgorny, #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D58755

llvm-svn: 355164
2019-03-01 01:45:01 +00:00
Jonas Hahnfeld 66c60d9d71 [compiler-rt] Build custom libcxx with libcxxabi
This changes add_custom_libcxx to also build libcxxabi and merges
the two into a static and hermetic library.
There are multiple advantages:
1) The resulting libFuzzer doesn't expose C++ internals and looks
   like a plain C library.
2) We don't have to manually link in libstdc++ to provide cxxabi.
3) The sanitizer tests cannot interfere with an installed version
   of libc++.so in LD_LIBRARY_PATH.

Differential Revision: https://reviews.llvm.org/D58013

llvm-svn: 354212
2019-02-17 12:16:20 +00:00
Jonas Hahnfeld a05d442391 [compiler-rt] Cleanup usage of C++ ABI library
Add missed value "libcxxabi" and introduce SANITIZER_TEST_CXX for linking
unit tests. This needs to be a full C++ library and cannot be libcxxabi.

Recommit r354132 which I reverted in r354153 because it broke a sanitizer
bot. This was because of the "fixes" for pthread linking, so I've removed
these changes.

Differential Revision: https://reviews.llvm.org/D58012

llvm-svn: 354198
2019-02-16 08:34:26 +00:00
Jonas Hahnfeld ea686e2845 Revert "[compiler-rt] Cleanup usage of C++ ABI library"
This reverts r354132 because it breaks sanitizer-x86_64-linux:
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux/builds/19915

llvm-svn: 354153
2019-02-15 18:25:26 +00:00
Jonas Hahnfeld 3cc63cfaa7 [compiler-rt] Cleanup usage of C++ ABI library
Add missed value "libcxxabi" and introduce SANITIZER_TEST_CXX for linking
unit tests. This needs to be a full C++ library and cannot be libcxxabi.

Differential Revision: https://reviews.llvm.org/D58012

llvm-svn: 354132
2019-02-15 14:30:18 +00:00
Peter Collingbourne 6141b037a9 gn build: Upgrade to NDK r19.
NDK r19 includes a sysroot that can be used directly by the compiler
without creating a standalone toolchain, so we just need a handful
of flags to point Clang there.

Differential Revision: https://reviews.llvm.org/D57733

llvm-svn: 353139
2019-02-05 05:10:19 +00:00
Petr Hosek e2c021d8b7 [CMake][compiler-rt] Enable statically linking unwinder and c++abi
Rather than guessing whether to use static or shared version of
unwinder and c++abi when using linking against the in-tree versions,
provide a CMake option to control this.

Differential Revision: https://reviews.llvm.org/D57492

llvm-svn: 352723
2019-01-31 03:38:43 +00:00
Shoaib Meenai 6e39af016f [compiler-rt] Add option to disable libc++ build
Having libc++ checked out doesn't necessarily mean it should be built;
for example, the same source tree might be used for multiple build
configurations, and libc++ might not build in some of those
configurations. Add an option to compiler-rt's build to disable building
libc++. This defaults to ON, so it shouldn't change any existing build
configurations.

Differential Revision: https://reviews.llvm.org/D56479

llvm-svn: 351117
2019-01-14 20:33:30 +00:00
Dimitry Andric a5afbce82b Set the default SANITIZER_CXX_ABI library to libc++ for FreeBSD, and
also mark it as a system library, like on macOS.

llvm-svn: 350020
2018-12-23 11:49:47 +00:00
Petr Hosek 54153c3b5e [CMake] When built with LLVM, not use `-Wl,-z,defs`
This matches standalone build behavior. PR28681

Differential Revision: https://reviews.llvm.org/D53686

Patch By: tabloid.adroit

llvm-svn: 345547
2018-10-29 22:16:56 +00:00
Stephen Hines 80e7d65a42 [sanitizer] Use -Wl,-z,global on Android for sanitizers except UBsan
Summary:
This essentially reverts r337010 since it breaks UBSan, which is used
for a few platform libraries. The "-z global" flag is now added for
Scudo as well. The only other sanitizer shared libraries are for asan
and hwasan, which have also been reinstated to use the global flag.

Reviewers: cryptoad, eugenis

Reviewed By: cryptoad

Subscribers: kubamracek, mgorny, delcypher, #sanitizers, nickdesaulniers, chh, kongyi, pirama, llvm-commits

Differential Revision: https://reviews.llvm.org/D52770

llvm-svn: 343599
2018-10-02 16:19:42 +00:00
Martin Storsjo 50de4518c5 [CMake] [MinGW] Build address sanitizer for MinGW if building with clang
Differential Revision: https://reviews.llvm.org/D51885

llvm-svn: 343074
2018-09-26 06:53:01 +00:00
Saleem Abdulrasool 73c39c0328 build: clean up some unnecessary cached variables
The CMAKE_<LANG>_ARCHIVE_FINISH rule doesn't need to be cleared for Darwin
static libraries.  Avoid resetting the variables in the SIP case.  If
CMAKE_RANLIB is cached, then CMake's Ninja generator will invoke ranlib during
installation, not due to the CMAKE_<LANG>_ARCHIVE_FINISH rule.

llvm-svn: 342511
2018-09-18 20:33:01 +00:00
Saleem Abdulrasool f5ebd70a67 build: fix standalone builds for compiler-rt on Darwin
When building static fat libraries, we need to ensure that we use libtool rather
than llvm-ar to create the library.  Duplicate the rules from LLVM to ensure
that we correctly build the fat libraries when building compiler-rt standalone.
This also requires that we duplicate the workaround for the `DYLD_LIBRARY_PATH`
for SIP.  Additionally, ensure that we set the `CMAKE_*_ARCHIVE_FINISH` variable
to ensure that we do not try to use `ranlib` on that target.

llvm-svn: 342425
2018-09-17 23:25:36 +00:00
Evgeniy Stepanov 4f0e10fff9 [hwasan] Add a (almost) no-interceptor mode.
Summary:
The idea behind this change is to allow sanitization of libc. We are prototyping on Bionic,
but the tool interface will be general enough (or at least generalizable) to support any other libc.

When libc depends on libclang_rt.hwasan, the latter can not interpose libc functions.
In fact, majority of interceptors become unnecessary when libc code is instrumented.

This change gets rid of most hwasan interceptors and provides interface for libc to notify
hwasan about thread creation and destruction events. Some interceptors (pthread_create)
are kept under #ifdef to enable testing with uninstrumented libc. They are expressed in
terms of the new libc interface.

The new cmake switch, COMPILER_RT_HWASAN_WITH_INTERCEPTORS, ON by default, builds testing
version of the library with the aforementioned pthread_create interceptor.
With the OFF setting, the library becomes more of a libc plugin.

Reviewers: vitalybuka, kcc, jfb

Subscribers: srhines, kubamracek, mgorny, jfb, llvm-commits

Differential Revision: https://reviews.llvm.org/D50922

llvm-svn: 340216
2018-08-20 21:49:15 +00:00
Petr Hosek 39f0860743 [CMake] Don't parse target triple except for arch
compiler-rt CMake build currently tries to parse the triple and then
put it back together, but doing so inherently tricky, and doing so
from CMake is just crazy and currently doesn't handle triples that
have more than three components. Fortunatelly, the CMake really only
needs the architecture part, which is typically the first component,
to construct variants for other architectures. This means we can keep
the rest of the triple as is and avoid the parsing altogether.

Differential Revision: https://reviews.llvm.org/D50548

llvm-svn: 339701
2018-08-14 18:01:19 +00:00
Petr Hosek d533fae6ef [CMake] Change the flag to use compiler-rt builtins to boolean
This changes the name and the type to what it was prior to r333037
which matches the name of the flag used in other runtimes: libc++,
libc++abi and libunwind. We don't need the type to be a string since
there's only binary choice between libgcc and compiler-rt unlike in
the case of C++ library where there're multiple options.

Differential Revision: https://reviews.llvm.org/D49325

llvm-svn: 337116
2018-07-15 03:05:20 +00:00
Petr Hosek 2d46cfedf2 [CMake] Don't use CLANG_DEFAULT_* values
These are not necessarily correct, just because Clang is configured
to use libc++ or compiler-rt as defaults doesn't mean that the host
compiler uses these as defaults as well. A more correct solution
would be to test the host compiler to check what the default actually
is as attempted in D46857.

Part of PR-38025.

Differential Revision: https://reviews.llvm.org/D49272

llvm-svn: 337033
2018-07-13 19:16:30 +00:00
Kostya Kortchinsky 4a547fb62d [sanitizer] Use -Wl,-z,global on Android
Summary:
Use `-Wl,-z,global` for all Sanitizer shared libraries on
Android. We want them to be in the global group
(https://android.googlesource.com/platform/bionic/+/master/android-changes-for-ndk-developers.md#changes-to-library-search-order)
to avoid any alloc/dealloc mismatch between the libc allocator & said library.

`audioserver` was one of the binary that exhibited the problem with Scudo,
this seems to fix it.

[edited for accuracy]

Reviewers: eugenis, alekseyshl

Reviewed By: eugenis

Subscribers: kubamracek, srhines, mgorny, delcypher, #sanitizers, llvm-commits

Differential Revision: https://reviews.llvm.org/D49198

llvm-svn: 337010
2018-07-13 15:31:05 +00:00
Stephen Hines 6812c28ef3 Add libcxxabi option back for sanitizer use.
Summary:
A prior refactoring accidentally dropped the case for using libc++abi as
the out-of-tree C++ runtime library for sanitizers. This patch restores
that functionality, which is used by Android, which can't depend on the
full libc++ for these libraries.

Reviewers: phosek, EricWF

Reviewed By: phosek

Subscribers: meikeb, kongyi, chh, mgorny, delcypher, llvm-commits, #sanitizers, pirama

Differential Revision: https://reviews.llvm.org/D49157

llvm-svn: 336749
2018-07-11 00:50:03 +00:00
Petr Hosek 887f26d470 Support for multiarch runtimes layout
This change adds a support for multiarch style runtimes layout, so in
addition to the existing layout where runtimes get installed to:

lib/clang/$version/lib/$os

Clang now allows runtimes to be installed to:

lib/clang/$version/$target/lib

This also includes libc++, libc++abi and libunwind; today those are
assumed to be in Clang library directory built for host, with the
new layout it is possible to install libc++, libc++abi and libunwind
into the runtime directory built for different targets.

The use of new layout is enabled by setting the
LLVM_ENABLE_RUNTIME_TARGET_DIR CMake variable and is supported by both
projects and runtimes layouts. The runtimes CMake build has been further
modified to use the new layout when building runtimes for multiple
targets.

Differential Revision: https://reviews.llvm.org/D45604

llvm-svn: 335809
2018-06-28 03:11:52 +00:00
Dan Liew bb78eef6b6 [CMake] Tidy up the organisation of compiler-rt when configured as a standalone
build with an IDE (e.g. Xcode) as the generator.

Previously the global `USE_FOLDERS` property wasn't set in standalone
builds leading to existing settings of FOLDER not being respected.

In addition to this there were several targets that appeared at the top
level that were not interesting and clustered up the view. These have
been changed to be displayed in "Compiler-RT Misc".

Now when an Xcode project is generated from a standalone compiler-rt
build the project navigator is much less cluttered. The interesting
libraries should appear in "Compiler-RT Libraries" in the IDE.

Differential Revision: https://reviews.llvm.org/D48378

llvm-svn: 335728
2018-06-27 12:56:34 +00:00
Petr Hosek aa6d13e501 [CMake] Support builtins as Clang default rtlib in compiler-rt
Use compiler-rt builtins when selected as default Clang rtlib and avoid
explicitly passing -rtlib= flag to avoid the "argument unused during
compilation" warning.

This is a partial alternative to D47094 that does not rely on compiler
runtime checks.

Differential Revision: https://reviews.llvm.org/D47115

llvm-svn: 333037
2018-05-22 22:58:48 +00:00
Petr Hosek 1ffaa48d4a [CMake] Support libc++ as Clang default stdlib in compiler-rt
Use libc++ when selected as default Clang stdlib and avoid checking
C++ compiler when using the in-tree version of libc++.

This is a partial alternative to D47094 that does not rely on compiler
runtime checks.

Differential Revision: https://reviews.llvm.org/D47100

llvm-svn: 333010
2018-05-22 18:33:27 +00:00
Petr Hosek 702d073642 Revert "[CMake] Reland "Make simple source used for CMake checks a C file""
This reverts commit rCRT332679 which doesn't quite work and will be
replaced by D47100 and D47115 which is a cleaner solution.

llvm-svn: 332871
2018-05-21 19:32:43 +00:00