After mailing list discussion on 11-13 March we would prefer to stick to a
single spelling of the long option.
This reverts commit 30035fe1a7c759c89ee62eb46efce6b3790fcc08.
llvm-svn: 237003
This is a starting point for using the TargetParser in Clang, in a simple
enough part of the code that can be used without disrupting the crazy
platform support that we need to be compatible with other toolchains.
Also adding a few FIXME on obvious places that need replacing, but those
cases will indeed break a few of the platform assumptions, as arch/cpu names
change multiple times in the driver.
Finally, I'm changing the "neon-vfpv3" behaviour to match standard NEON, since
-mfpu=neon implies vfpv3 by default in both Clang and LLVM. That option
string is still supported as an alias to "neon".
llvm-svn: 236901
GCC allows case-insensitive values for -mcpu, -march and -mtune options.
This patch implements the same behaviour for the -mcpu option.
Patch by Gabor Ballabas.
llvm-svn: 236859
llvm::Triple::getARMCPUForArch now returns nullptr for invalid -march
values, instead of silently translating it to arm7tdmi. Use this to
give an error message, which is consistent with how gcc behaves.
Differential Revision: http://reviews.llvm.org/D9602
llvm-svn: 236846
Summary:
Possible coverage levels are:
* -fsanitize-coverage=func - function-level coverage
* -fsanitize-coverage=bb - basic-block-level coverage
* -fsanitize-coverage=edge - edge-level coverage
Extra features are:
* -fsanitize-coverage=indirect-calls - coverage for indirect calls
* -fsanitize-coverage=trace-bb - tracing for basic blocks
* -fsanitize-coverage=trace-cmp - tracing for cmp instructions
* -fsanitize-coverage=8bit-counters - frequency counters
Levels and features can be combined in comma-separated list, and
can be disabled by subsequent -fno-sanitize-coverage= flags, e.g.:
-fsanitize-coverage=bb,trace-bb,8bit-counters -fno-sanitize-coverage=trace-bb
is equivalient to:
-fsanitize-coverage=bb,8bit-counters
Original semantics of -fsanitize-coverage flag is preserved:
* -fsanitize-coverage=0 disables the coverage
* -fsanitize-coverage=1 is a synonym for -fsanitize-coverage=func
* -fsanitize-coverage=2 is a synonym for -fsanitize-coverage=bb
* -fsanitize-coverage=3 is a synonym for -fsanitize-coverage=edge
* -fsanitize-coverage=4 is a synonym for -fsanitize-coverage=edge,indirect-calls
Driver tries to diagnose invalid flag usage, in particular:
* At most one level (func,bb,edge) must be specified.
* "trace-bb" and "8bit-counters" features require some level to be specified.
See test case for more examples.
Test Plan: regression test suite
Reviewers: kcc
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D9577
llvm-svn: 236790
Summary:
The next step is to add user-friendly control over these options
to driver via -fsanitize-coverage= option.
Test Plan: regression test suite
Reviewers: kcc
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D9545
llvm-svn: 236756
This patch adds support for the z13 architecture type. For compatibility
with GCC, a pair of options -mvx / -mno-vx can be used to selectively
enable/disable use of the vector facility.
When the vector facility is present, we default to the new vector ABI.
This is characterized by two major differences:
- Vector types are passed/returned in vector registers
(except for unnamed arguments of a variable-argument list function).
- Vector types are at most 8-byte aligned.
The reason for the choice of 8-byte vector alignment is that the hardware
is able to efficiently load vectors at 8-byte alignment, and the ABI only
guarantees 8-byte alignment of the stack pointer, so requiring any higher
alignment for vectors would require dynamic stack re-alignment code.
However, for compatibility with old code that may use vector types, when
*not* using the vector facility, the old alignment rules (vector types
are naturally aligned) remain in use.
These alignment rules are not only implemented at the C language level,
but also at the LLVM IR level. This is done by selecting a different
DataLayout string depending on whether the vector ABI is in effect or not.
Based on a patch by Richard Sandiford.
llvm-svn: 236531
LLVM r236120 renamed debug info IR constructs to use a `DI` prefix, now
that the `DIDescriptor` hierarchy has been gone for about a week. This
commit was generated using the rename-md-di-nodes.sh upgrade script
attached to PR23080, followed by running clang-format-diff.py on the
`lib/` portion of the patch.
llvm-svn: 236121
Embed UBSan runtime into TSan and MSan runtimes in the same as we do
in ASan. Extend UBSan test suite to also run tests for these
combinations.
llvm-svn: 235953
For now tsan_cxx and msan_cxx contain only operator new/delete
replacements. In the future, when we add support for running UBSan+TSan
and UBSan+MSan, they will also contain bits ubsan_cxx runtime.
llvm-svn: 235924
Before this patch, passing a non-existent absolute path to clang-cl would cause
stat'ing of impossible paths. For example, `clang-cl -c d:\adsfasdf.txt` would
cause a stat of
C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\LIBd:\asdfadsf.cc
llvm-svn: 235787
Stop relying on `cl::opt` to pass along the driver's decision to
preserve use-lists. Create a new `-cc1` option called
`-emit-llvm-uselists` that does the right thing (when -emit-llvm-bc).
Note that despite its generic name, it *doesn't* do the right thing when
-emit-llvm (LLVM assembly) yet. I'll hook that up soon.
This doesn't really change the behaviour of the driver. The default is
still to preserve use-lists for `clang -emit-llvm` and `clang
-save-temps`, and nothing else. But it stops relying on global state
(and also is a nicer interface for hackers using `clang -cc1`).
llvm-svn: 234962
Change `clang` to set `-preserve-bc-uselistorder` for the driver options
`-emit-llvm` and `-save-temps`. The former is useful for reproducing
results from `clang` in `opt` or `llc`, while the latter prevents
`-save-temps` from affecting the output. This is part of PR5680.
`-preserve-bc-uselistorder=true` is currently on by default, but a
follow-up commit in LLVM will reverse it.
llvm-svn: 234920
This patch generates a warning for invalid combination of '-mnan' and
'-march' options, it properly sets NaN encoding for a given '-march',
and it passes a proper NaN encoding to the assembler.
Patch by Vladimir Radosavljevic.
Differential Revision: http://reviews.llvm.org/D8170
llvm-svn: 234882
Follow-up to r234666. With this, the -m[no-]global-merge options
have the expected behavior. Previously, -mglobal-merge was ignored,
and there was no way of enabling the optimization.
llvm-svn: 234668
Summary:
tools::arm::getARMFloatABI() was falling back to guessing soft-float because
it wasn't seeing the GNUEABIHF environment from ComputeEffectivClangTriple
when it was called from gnutools::Assemble::ConstructJob.
Fix by using the effective clang triple in gnutools::Assemble, which now
matches the -triple flag used by cc1 and ClangAs jobs.
Reviewers: jvoung
Subscribers: rengolin, jfb, aemerson, cfe-commits
Differential Revision: http://reviews.llvm.org/D8902
llvm-svn: 234661
We don't actually need a real Mac sysroot to make the test pass, just a
linker. This makes the test pass in environments where no ld is on
PATH.
llvm-svn: 234533
The driver currently accepts but ignores the -freciprocal-math flag.
This patch passes the flag through and enables 'arcp' fast-math-flag
generation in IR.
Note that this change does not actually enable the optimization for
any target. The reassociation optimization that this flag specifies
was implemented by http://reviews.llvm.org/D6334 :
http://llvm.org/viewvc/llvm-project?view=revision&revision=222510
Because the optimization is done in the backend rather than IR,
the backend must be modified to understand instruction-level
fast-math-flags or a new function-level attribute must be created.
Also note that -freciprocal-math is independent of any target-specific
usage of reciprocal estimate hardware instructions. That requires
its own flag ('-mrecip').
https://llvm.org/bugs/show_bug.cgi?id=20912
llvm-svn: 234493
Adds ARM Cortex-R4 and R4F support and tests in Clang. Though Cortex-R4
support was present, the support for hwdiv in thumb-mode was not defined
or tested properly. This has also been added.
llvm-svn: 234488
This hooks up the /fp options as aliases for -f[no-]fast-math and
-f[no]-trapping-math. It probably doesn't match cl.exe's behaviour
completely (e.g. LLVM is currently never as precise as /fp:precise),
but it's close enough.
Differential revision: http://reviews.llvm.org/D8909
llvm-svn: 234449
Currently if you use -mmacosx-version-min or -mios-version-min without
specifying a version number, clang silently sets the minimum version to
"0.0.0". This is almost certainly not what was intended, so it is better
to report it as an error. rdar://problem/20433945
llvm-svn: 234270
Original message:
Don't use unique section names by default if using the integrated as.
This saves some IO and ccache space by not creating long section names. It
should work with every ELF linker.
llvm-svn: 234143
This reverts commit r233398, bringing back 233393 now that LLVM is fixed.
Original message:
Don't use unique section names by default if using the integrated as.
This saves some IO and ccache space by not creating long section names. It
should work with every ELF linker.
llvm-svn: 234101
This uses the same class metadata currently used for virtual call and
cast checks.
The new flag is -fsanitize=cfi-nvcall. For consistency, the -fsanitize=cfi-vptr
flag has been renamed -fsanitize=cfi-vcall.
Differential Revision: http://reviews.llvm.org/D8756
llvm-svn: 233874
Summary:
Change the way we use ASan and UBSan together. Instead of keeping two
separate runtimes (libclang_rt.asan and libclang_rt.ubsan), embed UBSan
into ASan and get rid of libclang_rt.ubsan. If UBSan is not supported on
a platform, all UBSan sources are just compiled into dummy empty object
files. UBSan initialization code (e.g. flag parsing) is directly called
from ASan initialization, so we are able to enforce correct
initialization order.
This mirrors the approach we already use for ASan+LSan. This change doesn't
modify the way we use standalone UBSan.
Test Plan: regression test suite
Reviewers: kubabrecka, zaks.anna, kcc, rsmith
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D8645
llvm-svn: 233860
The zEC12 provides the transactional-execution facility. This is exposed
to users via a set of builtin routines on other compilers. This patch
adds clang support to enable those builtins. In partciular, the patch:
- enables the transactional-execution feature by default on zEC12
- allows to override presence of that feature via the -mhtm/-mno-htm options
- adds a predefined macro __HTM__ if the feature is enabled
- adds support for the transactional-execution GCC builtins
- adds Sema checking to verify the __builtin_tabort abort code
- adds the s390intrin.h header file (for GCC compatibility)
- adds s390 sections to the htmintrin.h and htmxlintrin.h header files
Since this is first use of target-specific intrinsics on the platform,
the patch creates the include/clang/Basic/BuiltinsSystemZ.def file and
hooks it up in TargetBuiltins.h and lib/Basic/Targets.cpp.
An associated LLVM patch adds the required LLVM IR intrinsics.
For reference, the transactional-execution instructions are documented
in the z/Architecture Principles of Operation for the zEC12:
http://publibfp.boulder.ibm.com/cgi-bin/bookmgr/download/DZ9ZR009.pdf
The associated builtins are documented in the GCC manual:
http://gcc.gnu.org/onlinedocs/gcc/S_002f390-System-z-Built-in-Functions.html
The htmxlintrin.h intrinsics provided for compatibility with the IBM XL
compiler are documented in the "z/OS XL C/C++ Programming Guide".
llvm-svn: 233804
Add Tool and ToolChain support for clang to target the NaCl OS using the NaCl
SDK for x86-32, x86-64 and ARM.
Includes nacltools::Assemble and Link which are derived from gnutools. They
are similar to Linux but different enought that they warrant their own class.
Also includes a NaCl_TC in ToolChains derived from Generic_ELF with library
and include paths suitable for an SDK and independent of the system tools.
Differential Revision: http://reviews.llvm.org/D8590
llvm-svn: 233594
Unlike most of the other platforms supported by Clang, CloudABI only
supports static linkage, for the reason that global filesystem access is
prohibited. Functions provided by dlfcn.h are not present. As we know
that applications will not try to do any symbol lookups at run-time, we
can garbage collect unused code quite aggressively. Because of this, it
makes sense to enable -ffunction-sections and -fdata-sections by
default.
Object files will be a bit larger than usual, but the resulting binary
will not be affected, as the sections are merged again. However, when
--gc-sections is used, the linker is able to remove unused code far more
more aggressively. It also has the advantage that transitive library
dependencies only need to be provided to the linker in case that
functionality is actually used.
Differential Revision: http://reviews.llvm.org/D8635
Reviewed by: echristo
llvm-svn: 233299
Now that CloudABI's target information and header search logic for Clang
has been submitted, the only thing that remains to be done is adding
support for CloudABI's linker.
CloudABI uses Binutils ld, although there is some work to use lld
instead. This means that this code is largely based on what we use on
FreeBSD. There are some exceptions, however:
- Only static linking is performed. CloudABI does not support any
dynamically linked executables.
- CloudABI uses compiler-rt, libc++ and libc++abi unconditionally. Link
in these libraries instead of using libgcc_s, libstdc++, etc.
- We must ensure that the .eh_frame_hdr is present to make C++
exceptions work properly.
Differential Revision: http://reviews.llvm.org/D8250
llvm-svn: 233269
they enable/disable.
This fixes two things:
a) sse4 isn't actually a target feature, don't treat it as one.
b) we weren't correctly disabling sse4.1 when we'd pass -mno-sse4
after enabling it, thus passing preprocessor directives and
(soon) passing the function attribute as well when we shouldn't.
llvm-svn: 233223
Summary:
On my system, clang tries to invoke /path/to/arm-linux-androideabi-ld
as the linker for Android, and the regex inside the test file considers
this as unacceptable.
Reviewers: samsonov
Subscribers: tberghammer, aemerson, cfe-commits
Differential Revision: http://reviews.llvm.org/D8598
llvm-svn: 233211
Summary:
UBSan is now used in the same way as ASan, and is supported on
OSX and on iOS simulator. At the moment ASan and UBSan can't be used
together due to PR21112, but I hope to resolve it soon by
embedding UBSan into ASan.
Test Plan: regression test suite.
Reviewers: zaks.anna, kubabrecka
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D8471
llvm-svn: 233035
Get rid of "libclang_rt.san" library that used to contain
sanitizer_common pieces required by UBSan if it's used in a standalone
mode. Instead, build two variants of UBSan runtime: "ubsan" and
"ubsan_standalone" (same for "ubsan_cxx" and "ubsan_standalone_cxx").
Later "ubsan" and "ubsan_cxx" libraries will go away, as they will
embedded it into corresponding ASan runtimes.
llvm-svn: 233010
Decide whether or not to use thread-safe statics depending on whether or
not we have an explicit request from the driver. If we don't have an
explicit request, infer which behavior to use depending on the
compatibility version we are targeting.
N.B. CodeGen support is still ongoing.
llvm-svn: 232906
Summary:
We were claiming the -f*exceptions arguments when looking for the
RTTIMode. This makes us not warn about unused arguments if compiling a C
file with -fcxx-exceptions.
This patch fixes it by not claiming the exception-related arguments at
that point.
Reviewers: rsmith, samsonov
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D8507
llvm-svn: 232860
We are not able to make a reliable solution for using UBSan together
with other sanitizers with runtime support (and sanitizer_common).
Instead, we want to follow the path used for LSan: have a "standalone"
UBSan tool, and plug-in UBSan that would be explicitly embedded into
specific sanitizers (in short term, it will be only ASan).
llvm-svn: 232829
Summary: As discussed in D8097, we should provide corresponding linking flags when 'fveclib' is specified.
Reviewers: hfinkel
Differential Revision: http://reviews.llvm.org/D8362
llvm-svn: 232556
ARMv6K is another layer between ARMV6 and ARMV6T2. This is the Clang
side of the changes.
ARMV6 family LLVM implementation.
+-------------------------------------+
| ARMV6 |
+----------------+--------------------+
| ARMV6M (thumb) | ARMV6K (arm,thumb) | <- From ARMV6K and ARMV6M processors
+----------------+--------------------+ have support for hint instructions
| ARMV6T2 (arm,thumb,thumb2) | (SEV/WFE/WFI/NOP/YIELD). They can
+-------------------------------------+ be either real or default to NOP.
| ARMV7 (arm,thumb,thumb2) | The two processors also use
+-------------------------------------+ different encoding for them.
Patch by Vinicius Tinti.
llvm-svn: 232469
This scheme checks that pointer and lvalue casts are made to an object of
the correct dynamic type; that is, the dynamic type of the object must be
a derived class of the pointee type of the cast. The checks are currently
only introduced where the class being casted to is a polymorphic class.
Differential Revision: http://reviews.llvm.org/D8312
llvm-svn: 232241
For crashes with a VFS (ie, with modules), the -isysroot flag is often
necessary to reproduce the crash. This is especially true if some
modules need to be rebuilt, since without the sysroot they'll try to
read headers that are outside of the VFS.
I find it likely that we should keep some of the other -i flags in
this case as well, but I haven't seen that come up in practice yet so
it seems better to be conservative.
llvm-svn: 231997
When a crash report script doesn't work for a reproduction on your
machine for one reason or another, it can be really tricky to figure
out why not. The compiler version that crashed and the original
command line before stripping flags are very helpful when this comes
up.
llvm-svn: 231989
Support for the QPX vector instruction set, used on the IBM BG/Q supercomputer,
has recently been added to the LLVM PowerPC backend. This vector instruction
set requires some ABI modifications because the ABI on the BG/Q expects
<4 x double> vectors to be provided with 32-byte stack alignment, and to be
handled as native vector types (similar to how Altivec vectors are handled on
mainline PPC systems). I've named this ABI variant elfv1-qpx, have made this
the default ABI when QPX is supported, and have updated the ABI handling code
to provide QPX vectors with the correct stack alignment and associated
register-assignment logic.
llvm-svn: 231960
Using clang as a cross-compiler with the 'target' option could be confusing
for those inexperienced in the realm of cross compiling.
This patch would allow the use of all these four variants of the target option:
-target <triple>
--target <triple>
-target=<triple>
--target=<triple>
Patch by Gabor Ballabas.
llvm-svn: 231787
This is a recommit of r231150, reverted in r231409. Turns out
that -fsanitize=shift-base check implementation only works if the
shift exponent is valid, otherwise it contains undefined behavior
itself.
Make sure we check that exponent is valid before we proceed to
check the base. Make sure that we actually report invalid values
of base or exponent if -fsanitize=shift-base or
-fsanitize=shift-exponent is specified, respectively.
llvm-svn: 231711
simplicity in build systems, silence '-stdlib=libc++' when linking. Even
if we're not linking C++ code per-se, we may be passing this flag so
that when we are linking C++ code we pick up the desired standard
library. While most build systems already provide separate C and C++
compile flags, many conflate link flags. Sadly, CMake is among them
causing this warning in a libc++ selfhost.
llvm-svn: 231559
It's not that easy. If we're only checking -fsanitize=shift-base we
still need to verify that exponent has sane value, otherwise
UBSan-inserted checks for base will contain undefined behavior
themselves.
llvm-svn: 231409
Summary:
When using the IAS from clang, the 'target-abi' option gets passed to cc1as, but cc1as doesn't know about it and gives an "unknown argument" error.
This is fixed by adding the 'CC1AsOption' flag to the 'target-abi' option in CC1Options.td.
Reviewers: atanasyan, echristo, dsanders
Reviewed By: dsanders
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D7903
llvm-svn: 231244
-fsanitize=shift is now a group that includes both these checks, so
exisiting users should not be affected.
This change introduces two new UBSan kinds that sanitize only left-hand
side and right-hand side of shift operation. In practice, invalid
exponent value (negative or too large) tends to cause more portability
problems, including inconsistencies between different compilers, crashes
and inadequeate results on non-x86 architectures etc. That is,
-fsanitize=shift-exponent failures should generally be addressed first.
As a bonus, this change simplifies CodeGen implementation for emitting left
shift (separate checks for base and exponent are now merged by the
existing generic logic in EmitCheck()), and LLVM IR for these checks
(the number of basic blocks is reduced).
llvm-svn: 231150
Summary:
There is no -no-pie flag that can override this, so making it default
to being on for Android means it is no longer possible to create
non-PIE executables on Android. While current versions of Android
support (and the most recent requires) PIE, ICS and earlier versions
of Android cannot run PIE executables, so this needs to be optional.
Reviewers: srhines
Reviewed By: srhines
Subscribers: thakis, volkalexey, cfe-commits
Differential Revision: http://reviews.llvm.org/D8015
llvm-svn: 231091
Modules and Tooling tests in particular tend to want to change the cwd,
so we were missing test coverage in this area on Windows. It should now
be easier to write such portable tests.
llvm-svn: 231029
Change -fsanitize-memory-track-origins to be equivalent to
-fsanitize-memory-track-origins=2.
Track-origins=2 provides a lot more detailed reports at the cost of
some additional slowdown (ranging from none to, sometimes, 3x; ~3% average on
SPEC2006).
llvm-svn: 230644
There is no supported toolchain which provides headers / libs / object
files specific to the mips32r[3|5] and mips64r[3|5] ISA. So select "r2"
specific folders when they are available.
http://reviews.llvm.org/D7879
llvm-svn: 230611
While it's true that we don't create the PDB as requested on the command
line, this is a well-documented limitation. Warning about it doesn't
help people using legacy build systems with clang-cl, and it makes the
clang-cl self-host very noisy.
llvm-svn: 230527
VS 2013 is the minimum supported version, so it's reasonable for Clang
to simulate this by default. This also simplifies the clang-cl
self-host, since we have the 18.00 version check.
llvm-svn: 230243
The patch teaches the clang's driver to understand new MIPS ISA names,
pass appropriate options to the assembler, defines corresponding macros etc
http://reviews.llvm.org/D7737
llvm-svn: 230092
This patch introduces the -fsanitize=cfi-vptr flag, which enables a control
flow integrity scheme that checks that virtual calls take place using a vptr of
the correct dynamic type. More details in the new docs/ControlFlowIntegrity.rst
file.
It also introduces the -fsanitize=cfi flag, which is currently a synonym for
-fsanitize=cfi-vptr, but will eventually cover all CFI checks implemented
in Clang.
Differential Revision: http://reviews.llvm.org/D7424
llvm-svn: 230055
For now -funique-section-names is the default, so no change in default behavior.
The total .o size in a build of llvm and clang goes from 241687775 to 230649031
bytes if -fno-unique-section-names is used.
llvm-svn: 230031
This patch removes the huge blob of code that is dealing with
rtti/exceptions/sanitizers and replaces it with:
A ToolChain function which, for a given set of Args, figures out if rtti
should be:
- enabled
- disabled implicitly
- disabled explicitly
A change in the way SanitizerArgs figures out what sanitizers to enable
(or if it should error out, or warn);
And a check for exceptions/rtti interaction inside addExceptionArgs.
The RTTIMode algorithm is:
- If -mkernel, -fapple-kext, or -fno-rtti are passed, rtti was disabled explicitly;
- If -frtti was passed or we're not targetting the PS4, rtti is enabled;
- If -fexceptions or -fcxx-exceptions was passed and we're targetting
the PS4, rtti was enabled implicitly;
- If we're targetting the PS4, rtti is disabled implicitly;
- Otherwise, rtti is enabled;
Since the only flag needed to pass to -cc1 is -fno-rtti if we want to
disable it, there's no problem in saying rtti is enabled if we're
compiling C code, so we don't look at the input file type.
addExceptionArgs now looks at the RTTIMode and warns that rtti is being
enabled implicitly if targetting the PS4 and exceptions are on. It also
errors out if, targetting the PS4, -fno-rtti was passed, and exceptions
were turned on.
SanitizerArgs now errors out if rtti was disabled explicitly and the vptr
sanitizer was enabled implicitly, but just turns off vptr if rtti is
disabled but -fsanitize=undefined was passed.
Also fixed tests, removed duplicate name from addExceptionArgs comment,
and added one or two surrounding lines when running clang-format.
This changes test/Driver/fsanitize.c to make it not expect a warning when
passed -fsanitize=undefined -fno-rtti, but expect vptr to not be on.
Removed all users and definition of SanitizerArgs::sanitizesVptr().
Reviewers: samsonov
Subscribers: llvm-commits, samsonov, rsmith
Differential Revision: http://reviews.llvm.org/D7525
llvm-svn: 229801
Add some of the missing M and R class Cortex CPUs, namely:
Cortex-M0+ (called Cortex-M0plus for GCC compatibility)
Cortex-M1
SC000
SC300
Cortex-R5
llvm-svn: 229661
This is typically used to suppress warnings about calling snprintf and
other "deprecated" POSIX functions. Accepting this flag helps avoid tons
of useless warnings when trying out clang-cl on a new project.
Patch by Scott Graham!
llvm-svn: 229583
The /volatile:ms semantics turn volatile loads and stores into atomic
acquire and release operations. This distinction is important because
volatile memory operations do not form a happens-before relationship
with non-atomic memory. This means that a volatile store is not
sufficient for implementing a mutex unlock routine.
Differential Revision: http://reviews.llvm.org/D7580
llvm-svn: 229082
Richard Barton