Summary:
[ Copied from https://llvm.org/bugs/show_bug.cgi?id=25597 ]
Clang support for DragonFly BSD is lagging a bit, resulting in poor
support for c++.
DragonFlyBSD is unique in that it has two base compilers. At the time
of the last Clang update for DragonFly, these compilers were GCC 4.4 and
GCC 4.7 (default).
With DragonFly Release 4.2, GCC 4.4 was replaced with GCC 5.0, partially
because the C++11 support of GCC 4.7 was incomplete. The DragonFly
project will Release version 4.4 soon.
This patch updates the Clang driver to use libstdc++ from GCC 5.2 The
support for falling back to the alternate compiler was removed for two
reasons:
1) The last release to use GCC 4.7 is DF 4.0 which has already reached EOL
2) GCC 4.7 libstdc++ is insufficient for many "ports"
Therefore, I think it is reasonable that the development version of
clang expects GCC 5.2 to be in place and not try to fall back to another
compiler.
The attached patch will do this. The Tools.cpp file was signficantly
modified to fix the linking which had been changed somewhere along the
line. The rest of the changes should be self-explanatory.
Reviewers: joerg, rsmith, davide
Subscribers: jrmarino, davide, cfe-commits
Differential Revision: http://reviews.llvm.org/D15166
llvm-svn: 256467
The /Brepro flag controls whether or not the compiler should embed
timestamps into the object file. Object files which do not embed
timestamps are not suitable for incremental linking but are suitable for
hermetic build systems and staged self-hosts of clang.
A normal clang spelling of this flag has been added,
-mincremental-linker-compatible.
llvm-svn: 256204
Adds driver options named -glldb and -gsce to mean -g plus tuning for
lldb and SCE debuggers respectively; the existing -ggdb option does
the same for gdb. Existing options -ggdb0, -ggdb1 etc. unpack into
-ggdb -g<N>. (There will not be -glldb<N> or -gsce<N> options.) The
tuning gets a target-specific default in the driver, and is passed
into cc1 with the new -debugger-tuning option.
As fallout, fixes where '-gsplit-dwarf -g0' would ignore the -g0 part
on Linux.
Differential Revision: http://reviews.llvm.org/D15651
llvm-svn: 256104
r245667 changed -static so that it doesn't override an explicit -fPIC
option, but -static should still change the default for Darwin for -fno-PIC.
This matches longstanding GCC and Clang behavior on Darwin and changing it
would be disruptive, with no significant benefit.
http://reviews.llvm.org/D15455
rdar://problem/23811045
llvm-svn: 256026
This begins minimal support for invoking 'ld' from clang for WebAssembly
targets.
Differential Revision: http://reviews.llvm.org/D15586
llvm-svn: 255848
".exe" extension is inherently checked by llvm::fs::can_execute()
This patch fixes the linker extension in clang driver and updates the
unit test to accommodate the the check string on windows.
Differential Revision:http://reviews.llvm.org/D15577
llvm-svn: 255814
Currently it's easy to break CUDA compilation by passing
"-isystem /path/to/cuda/include" to compiler which leads to
compiler including real cuda_runtime.h from there instead
of the wrapper we need.
Renaming the wrapper ensures that we can include the wrapper
regardless of user-specified include paths and files.
Differential Revision: http://reviews.llvm.org/D15534
llvm-svn: 255802
Clang-side cross-DSO CFI.
* Adds a command line flag -f[no-]sanitize-cfi-cross-dso.
* Links a runtime library when enabled.
* Emits __cfi_slowpath calls is bitset test fails.
* Emits extra hash-based bitsets for external CFI checks.
* Sets a module flag to enable __cfi_check generation during LTO.
This mode does not yet support diagnostics.
llvm-svn: 255694
This patch enables soft float support for ppc32 architecture and fixes
the ABI for variadic functions. This is the first in a set of patches
for soft float support in LLVM.
Patch by Strahinja Petrovic.
Differential Revision: http://reviews.llvm.org/D13351
llvm-svn: 255515
- Removed support for hexagonv3 and earlier.
- Added handling of hexagonv55 and hexagonv60.
- Added handling of target features (hvx, hvx-double).
- Updated paths to reflect current directory layout.
llvm-svn: 255502
This improves the coverage for the multilib directories used for ARM. Also add
tests covering the internal triple (thumbv7-*). The Juno board can be run in
this configuration.
llvm-svn: 255328
Summary:
Adds new option -fthinlto-index=<file> to invoke the LTO pipeline
along with function importing via clang using the supplied function
summary index file. This supports invoking the parallel ThinLTO
backend processes in a distributed build environment via clang.
Additionally, this causes the module linker to be invoked on the bitcode
file being compiled to perform any necessary promotion and renaming of
locals that are exported via the function summary index file.
Add a couple tests that confirm we get expected errors when we try to
use the new option on a file that isn't bitcode, or specify an invalid
index file. The tests also confirm that we trigger the expected function
import pass.
Depends on D15024
Reviewers: joker.eph, dexonsmith
Subscribers: joker.eph, davidxl, cfe-commits
Differential Revision: http://reviews.llvm.org/D15025
llvm-svn: 254927
This patch is a fix to r252901 which changed the behavior of
clang driver. In the presence of "-nostdlib" none of the standard
libraries should be passed to link line.
Differential Revision: http://reviews.llvm.org/D15130
llvm-svn: 254535
handling is corrected, the primary reason for forcing IAS as default is
gone and the remaining issues are still somewhat problematic in common
situations.
llvm-svn: 254199
This adds the "+profile" and +noprofile" suffixes for the -march and
-mcpu options, to allow enabling or disabling the options Statistical
Profiling Extension to ARMv8.2-A.
Differential Revision: http://reviews.llvm.org/D15023
llvm-svn: 254161
This adds new values for the -march option (armv8.2a and armv8.2-a,
which are aliases of each other), and new suffixes for the -march and
-mcpu options (+fp16 and +nofp16), to allow targeting the ARMv8.2-A
architecture and it's optional half-precision floating-point extension.
Differential Revision: http://reviews.llvm.org/D15022
llvm-svn: 254160
The Driver only checked if nostdlib was set when deciding to add
reserved_lib_stdcxx, but as nostdlib is always exactly nodefaultlibs and
nostartfiles we should be checking one (clearly nodefaultlibs in the
case) as well. This appears to be the only such instance of this in the
codebase.
Differential Revision: http://reviews.llvm.org/D14935
llvm-svn: 253990
hard coding /usr makes little sense for mingw-w64.
If we have portable toolchains having /usr breaks that.
If the clang we use is in /usr/bin or /usr/sbin etc this will
still detect as though it was hard coded to /usr
This makes the most sense going forward for mingw-w64 toolchains
on both linux and mac
Differential Revision: http://reviews.llvm.org/D14164
llvm-svn: 253898
(Re-apply patch after bug fixing)
This diff makes sure that the driver does not pass
-fomit-frame-pointer or -momit-leaf-frame-pointer to
the frontend when -pg is used. Currently, clang gives
an error if -fomit-frame-pointer is used in combination
with -pg, but -momit-leaf-frame-pointer was forgotten.
Also, disable frame pointer elimination in the frontend
when -pg is set.
Patch by Stefan Kempf.
llvm-svn: 253886
This diff makes sure that the driver does not pass
-fomit-frame-pointer or -momit-leaf-frame-pointer to
the frontend when -pg is used. Currently, clang gives
an error if -fomit-frame-pointer is used in combination
with -pg, but -momit-leaf-frame-pointer was forgotten.
Also, disable frame pointer elimination in the frontend
when -pg is set.
Patch by Stefan Kempf.
llvm-svn: 253846
Cross compiling from linux and OSX results in Error: Exec format.
This is because the linker is expecting ELF formated objects.
By passing the target we can explicitly tell the linker that
it should be linking COFF objects regardless of the host.
llvm-svn: 253813
This allows us to construct Linux toolchains without a valid linker. This
is needed for example to build a CUDA device toolchain after r253385.
llvm-svn: 253707
Summary: This code is a bit undesirable, but it gets clang to work with the autoconf and cmake-built libclang_rt.profile libraries.
Reviewers: bogner
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D14847
llvm-svn: 253625
Currently clang requires several additional command
line options in order to enable new features needed
during CUDA compilation. This patch makes these
options default.
* Automatically include cuda_runtime.h if we've found
a valid CUDA installation.
* Disable automatic CUDA header inclusion during unit tests.
* Added test case for command line construction.
* Enabled target overloads and relaxed call checks that are
needed in order to include CUDA headers.
* Added CUDA-7.5 installation path to the CUDA installation search list.
* Define __CUDA__ macro to indicate CUDA compilation.
llvm-svn: 253389
- added detection of libdevice bitcode file and API to find one appropriate for the GPU we're compiling for.
- pass additional cc1 options for linking with detected libdevice bitcode
- added -nocudalib to prevent automatic linking with libdevice
- added test cases to verify new functionality
Differential Revision: http://reviews.llvm.org/D14556
llvm-svn: 253387
In order to compile a CUDA file clang must be able to find
include files for both both host and device.
This patch passes AuxToolchain to AddPreprocessingOptions and
uses it to add include paths for the opposite side of compilation.
We also must be able to find CUDA include files. If the driver
found CUDA installation, it adds appropriate include path
to CUDA headers. This can be disabled with '-nocudainc'.
- Added include paths for the opposite side of compilation.
- Added include paths to detected CUDA installation.
- Added -nocudainc to prevent adding CUDA include path.
- Added test cases to verify new functionality.
Differential Revision: http://reviews.llvm.org/D13170
llvm-svn: 253386
Clang needs to know target triple for both sides of compilation so that
preprocessor macros and target builtins from both sides are available.
This change augments Compilation class to carry information about
toolchains used during different CUDA compilation passes and refactors
BuildActions to use it when it constructs CUDA jobs.
Removed DeviceTriple from CudaHostAction/CudaDeviceAction as it's no
longer needed.
Differential Revision: http://reviews.llvm.org/D13144
llvm-svn: 253385
"-arch armv7k" is only normally used with a watchos target, but Clang doesn't
stop you from giving a "-miphoneos-version-min" option too, converting the
triple to "thumbv7k-apple-ios". In this case the backend will decide to use
SjLj exceptions, so Clang needs to agree so it can create the correct
predefines.
Fortunately, there's a handy function to make the decision for us now.
llvm-svn: 253355
Last time, this caused two Windows buildbots and a single ARM buildbot to fail.
I XFAIL'd the failing test on win32,win64 machines in order to see if the ARM
buildbot complains again.
llvm-svn: 252901
This currently changes the default toward the more historic -Av8/-Av9,
but as discussed with James Y Knight, consistency is for now more
important than figuring out which default CPU each OS should be using.
llvm-svn: 252571
When adding profiling instrumentation, use libclang_rt.profile_tvos.a
for TVOS targets and libclang_rt.profile_watchos.a for WatchOS targets.
I've also fixed up a comment and added an assert() that prevents us from
defaulting to an incorrect platform.
Differential Revision: http://reviews.llvm.org/D14521
Reviewed-by: t.p.northover
llvm-svn: 252558
is not defined for 32bit mode, but __sparcv9 is. Pass down the correct
-target-cpu flags to the backend, so that instruction restrictions are
applied correctly. Pass down the correct -A flag when not using IAS.
The latter is limited to NetBSD targets in this commit.
llvm-svn: 252545
The -meabi flag to control LLVM EABI version.
Without '-meabi' or with '-meabi default' imply LLVM triple default.
With '-meabi gnu' sets EABI GNU.
With '-meabi 4' or '-meabi 5' set EABI version 4 and 5 respectively.
A similar patch was introduced in LLVM.
Patch by Vinicius Tinti.
llvm-svn: 252463
We're currently in process of porting TSan to OS X, and quite a few of the initial support in the runtime library has already landed in trunk. This patch actually enables "-fsanitize=thread" in the frontend.
Differential Revision: http://reviews.llvm.org/D14440
llvm-svn: 252310
This sets the mostly expected Darwin default ABI options for these two
platforms. Active changes from these defaults for watchOS are in a later patch.
llvm-svn: 251708
This patch should add support for almost all command-line options and
driver tinkering necessary to produce a correct "clang -cc1"
invocation for watchOS and tvOS.
llvm-svn: 251706
This reverts commit r251695. Debug is meant to be done off tree, not use the buildbots
experiments. I'll help investigate this problem off trunk.
llvm-svn: 251696
This should be a NFC for every toolchain other than mips-mti-linux (where we
print the list of directories searched for crt files). It will soon be
reverted once we hit the clang-cmake-armv7-a15-selfhost-neon buildbot.
llvm-svn: 251695
The original commit in r249137 added the mips-mti-linux toolchain. However,
the newly added tests of that commit failed in few buildbots. This commit
re-applies the original changes but XFAILs the test file which caused
the buildbot failures. This will allow us to examine what's going wrong
without having to commit/revert large changes.
llvm-svn: 251633
Indicate support for ASAN on the CrossWindows toolchain. Although this is
insufficient, this at least permits the handling of the driver flag.
llvm-svn: 251598
that has a thumb only CPU by default (cortex-m3), and when using the assembler,
the default thumb state of the CPU does not get passed via the triple to LLVM:
$ clang -target thumbv7m-none-eabi -c -v test.s
clang -cc1as ... -triple armv7m-none--eabi ... test.s
Differential Revision: http://reviews.llvm.org/D14121
llvm-svn: 251507
Summary: This is a follow on to post review comments on revision r248276.
Patch by Scott Egerton.
Reviewers: vkalintiris, dsanders
Subscribers: joerg, rengolin, cfe-commits
Differential Revision: http://reviews.llvm.org/D13100
llvm-svn: 251430
Create undef reference to profile hook symbol when
PGO instrumentation is turned on. This allows
LLVM to omit emission of hook variable use method
for every single module instrumented.
llvm-svn: 251385
Previously, __weak was silently accepted and ignored in MRC mode.
That makes this a potentially source-breaking change that we have to
roll out cautiously. Accordingly, for the time being, actual support
for __weak references in MRC is experimental, and the compiler will
reject attempts to actually form such references. The intent is to
eventually enable the feature by default in all non-GC modes.
(It is, of course, incompatible with ObjC GC's interpretation of
__weak.)
If you like, you can enable this feature with
-Xclang -fobjc-weak
but like any -Xclang option, this option may be removed at any point,
e.g. if/when it is eventually enabled by default.
This patch also enables the use of the ARC __unsafe_unretained qualifier
in MRC. Unlike __weak, this is being enabled immediately. Since
variables are essentially __unsafe_unretained by default in MRC,
the only practical uses are (1) communication and (2) changing the
default behavior of by-value block capture.
As an implementation matter, this means that the ObjC ownership
qualifiers may appear in any ObjC language mode, and so this patch
removes a number of checks for getLangOpts().ObjCAutoRefCount
that were guarding the processing of these qualifiers. I don't
expect this to be a significant drain on performance; it may even
be faster to just check for these qualifiers directly on a type
(since it's probably in a register anyway) than to do N dependent
loads to grab the LangOptions.
rdar://9674298
llvm-svn: 251041
In this patch, the file static method addProfileRT is
moved to be a virtual member function of base ToolChain class.
This allows derived toolchain to override the default behavior
easily and make it consistent with Darwin toolchain (a TODO was
added for this refactoring - now removed). A new helper method
is also introduced to test if instrumentation profile option
is turned on or not.
Differential Revision: http://reviews.llvm.org/D13326
llvm-svn: 250994
Since r249754 MemorySanitizer should work equally well for PIE and
non-PIE executables on Linux/x86_64.
Beware, with this change -fsanitize=memory no longer adds implicit
-fPIE -pie compiler/linker flags on Linux/x86_64.
This is a re-land of r250941, limited to Linux/x86_64 + a very minor
refactoring in SanitizerArgs.
llvm-svn: 250949
Since r249754 MemorySanitizer should work equally well for PIE and
non-PIE executables.
Beware, with this change -fsanitize=memory no longer adds implicit
-fPIE -pie compiler/linker flags, unless the target defaults to PIE.
llvm-svn: 250941
Summary: It breaks the build for the ASTMatchers
Subscribers: klimek, cfe-commits
Differential Revision: http://reviews.llvm.org/D13893
llvm-svn: 250827
Summary:
Similar to rL248426 (which was a followup to rL248379 and rL248424), add the
required libraries for OpenMP on the linker command line, and update the test
case.
Reviewers: emaste, theraven, joerg
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D13822
llvm-svn: 250657
This recommits r250398 with fixes to the tests for bot failures.
Add "-target x86_64-unknown-linux" to the clang invocations that
check for the gold plugin.
llvm-svn: 250455
Rolling this back for now since there are a couple of bot failures on
the new tests I added, and I won't have a chance to look at them in detail
until later this afternoon. I think the new tests need some restrictions on
having the gold plugin available.
This reverts commit r250398.
llvm-svn: 250402
Summary:
Add clang support for -flto=thin option, which is used to set the
EmitFunctionSummary code gen option on compiles.
Add -flto=full as an alias to the existing -flto.
Add tests to check for proper overriding of -flto variants on the
command line, and convert grep tests to FileCheck.
Reviewers: dexonsmith, joker.eph
Subscribers: davidxl, cfe-commits
Differential Revision: http://reviews.llvm.org/D11908
llvm-svn: 250398
There was a minor problem with a test. Sorry for the noise yesterday.
This patch adds missing pieces to clang, including the PS4 toolchain
definition, added warnings, PS4 defaults, and Driver changes needed for
our compiler.
A patch by Filipe Cabecinhas, Pierre Gousseau and Katya Romanova!
Differential Revision: http://reviews.llvm.org/D13482
llvm-svn: 250293
Resubmitting the patch.
This patch adds missing pieces to clang, including the PS4 toolchain
definition, added warnings, PS4 defaults, and Driver changes needed for
our compiler.
A patch by Filipe Cabecinhas, Pierre Gousseau and Katya Romanova!
Differential Revision: http://reviews.llvm.org/D13482
llvm-svn: 250262
definition, added warnings, PS4 defaults, and Driver changes needed for
our compiler.
A patch by Filipe Cabecinhas, Pierre Gousseau and Katya Romanova!
Differential Revision: http://reviews.llvm.org/D13482
llvm-svn: 250252
This is what most people want anyways. Clang -cc1's main() will override
this but for other tools this is the most sensible default and avoids
some work.
llvm-svn: 250164
Add support for the `-fdebug-prefix-map=` option as in GCC. The syntax is
`-fdebug-prefix-map=OLD=NEW`. When compiling files from a path beginning with
OLD, change the debug info to indicate the path as start with NEW. This is
particularly helpful if you are preprocessing in one path and compiling in
another (e.g. for a build cluster with distcc).
Note that the linearity of the implementation is not as terrible as it may seem.
This is normally done once per file with an expectation that the map will be
small (1-2) entries, making this roughly linear in the number of input paths.
Addresses PR24619.
llvm-svn: 250094
C++ exceptions are still off by default, which is similar to how C++
cleanups are off by default in MSVC.
If you use clang instead of clang-cl, exceptions are also still off by
default. In the future, when C++ EH is proven to be stable, we may flip
the default for that driver to be consistent with other platforms.
llvm-svn: 249704
With this change, most 'g' options are rejected by CompilerInvocation.
They remain only as Driver options. The new way to request debug info
from cc1 is with "-debug-info-kind={line-tables-only|limited|standalone}"
and "-dwarf-version={2|3|4}". In the absence of a command-line option
to specify Dwarf version, the Toolchain decides it, rather than placing
Toolchain-specific logic in CompilerInvocation.
Also fix a bug in the Windows compatibility argument parsing
in which the "rightmost argument wins" principle failed.
Differential Revision: http://reviews.llvm.org/D13221
llvm-svn: 249655
r249137 added support for the new mips-mti-linux toolchain. However,
the new tests of that commit, broke some buildbots because they didn't use
the correct regular expressions to capture the filename of Clang & LLD.
This commit re-applies the changes of r249137 and fixes the tests in
r249137 in order to match the filenames of the Clang and LLD executable.
llvm-svn: 249294
In versions of clang prior to r238238, __declspec was recognized as a keyword in
all modes. It was then changed to only be enabled when Microsoft or Borland
extensions were enabled (and for CUDA, as a temporary measure). There is a
desire to support __declspec in Playstation code, and possibly other
environments. This commit adds a command-line switch to allow explicit
enabling/disabling of the recognition of __declspec as a keyword. Recognition
is enabled by default in Microsoft, Borland, CUDA, and PS4 environments, and
disabled in all other environments.
Patch by Warren Ristow!
llvm-svn: 249279
The Windows on ARM ABI recommends that FPO be disabled. This is since the
Windows on ARM ABI uses the FP for fast stack walking. By paying the slight
cost of the loss of registers, a much faster backtrace is possible by using the
frame pointer since the pdata need not be consulted. Furthermore, even if pdata
is not available, you can still more easily reconstruct the stack.
llvm-svn: 249227
Reapply r248935.
Usually, when using LTO with a clang installation newer than the
system's one, there's a libLTO.dylib version mismatch and LTO fails. One
solution to this is to make ld point to the right libLTO.dylib by
changing DYLD_LIBRARY_PATH.
However, ld64 supports specifying the complete path to the desired
libLTO.dylib through the -lto_library option. This commit adds support
for the clang driver to use this option whenever it's capable of finding
a libLTO.dylib in clang's installed library directory. This way, we
don't need to rely on DYLD_LIBRARY_PATH nor get caught by version
mismatches.
Differential Revision: http://reviews.llvm.org/D13117
rdar://problem/7363476
llvm-svn: 249143
Summary:
This new toolchain uses primarily LLVM-based tools, eg. compiler-rt, lld,
libcxx, etc. Because of this, it doesn't require neither an existing GCC
installation nor a GNU environment. Ideally, in a follow-up patch we
would like to add a new --{llvm|clang}-toolchain option (similar to
--gcc-toolchain) in order to allow the use of this toolchain with
independent Clang builds. For the time being, we use the --sysroot
option just to test the correctness of the paths generated by the
driver.
Reviewers: atanasyan, dsanders, rsmith
Subscribers: jfb, tberghammer, danalbert, srhines, dschuff, cfe-commits
Differential Revision: http://reviews.llvm.org/D13340
llvm-svn: 249137
Summary:
This patch moves getCompilerRT() from the clang::driver::tools namespace to
the ToolChain class. This is needed for multilib toolchains that need to
place their libraries in Clang's resource directory with a layout that is
different from the default one.
Reviewers: atanasyan, rsmith
Subscribers: tberghammer, danalbert, srhines, cfe-commits
Differential Revision: http://reviews.llvm.org/D13339
llvm-svn: 249030
Usually, when using LTO with a clang installation newer than the
system's one, there's a libLTO.dylib version mismatch and LTO fails. One
solution to this is to make ld point to the right libLTO.dylib by
changing DYLD_LIBRARY_PATH.
However, ld64 supports specifying the complete path to the desired
libLTO.dylib through the -lto_library option. This commit adds support
for the clang driver to use this option whenever it's capable of finding
a libLTO.dylib in clang's installed library directory. This way, we
don't need to rely on DYLD_LIBRARY_PATH nor get caught by version
mismatches.
Differential Revision: http://reviews.llvm.org/D13117
rdar://problem/7363476
llvm-svn: 248932
ARM EABI adds target attributes to the object file. Amongst the attributes that
are emitted is the VFP argument passing (Hard vs Soft). The linker is
responsible for checking these attributes and erroring on mismatches. This
causes problems for the compiler-rt builtins when targeting both hard and
soft. Because both of these options name the builtins compiler-rt component
the same (libclang_rt.builtins-arm.a or libclang_rt.builtins-arm-android). GCC
is able to get away with this as it does one target per toolchain. This
changes the naming convention for the ARM compiler-rt builtins to differentiate
between HF and Soft. Although this means that compiler-rt may be duplicated, it
enables supporting both variants from a single toolchain. A similar approach is
taken by the Darwin toolchain, naming the library to differentiate between the
calling conventions.
llvm-svn: 248649
logic to select an alternate target based on the executable it was
called as. For instance, if you symlink i686-linux-android-gcc to clang
and invoke it, the driver will act as though it were called with another
argument ("-target i686-linux-android"). This leads to visible effects
even in syntax-only compilations (like the ANDROID preprocessor symbol
being defined).
This behavior is not replicated for tool invocations--for instance,
clang::createInvocationFromCommandLine will not choose an alternate
target based on ArgList[0]. This means that configurations stored in
compilation databases aren't accurately replayed.
This patch separates the logic for selecting a mode flag and target from
the executable name into a new member function on ToolChain. It should
have no functional effects (but will allow other code to reuse the
target/mode selection logic).
Patch by Luke Zarko!
llvm-svn: 248592
definition, added warnings, PS4 defaults, and Driver changes needed for
our compiler.
A patch by Filipe Cabecinhas, Pierre Gousseau and Katya Romanova!
Differential Revision: http://reviews.llvm.org/D11279
llvm-svn: 248546