Summary:
Add -ftrivial-auto-var-init-stop-after= to limit the number of times
stack variables are initialized when -ftrivial-auto-var-init= is used to
initialize stack variables to zero or a pattern. This flag can be used
to bisect uninitialized uses of a stack variable exposed by automatic
variable initialization, such as http://crrev.com/c/2020401.
Reviewers: jfb, vitalybuka, kcc, glider, rsmith, rjmccall, pcc, eugenis, vlad.tsyrklevich
Reviewed By: jfb
Subscribers: phosek, hubert.reinterpretcast, srhines, MaskRay, george.burgess.iv, dexonsmith, inglorion, gbiv, llozano, manojgupta, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D77168
rL82131 changed -O from -O1 to -O2, because -O1 was not different from
-O2 at that time.
GCC treats -O as -O1 and there is now work to make -O1 meaningful.
We can change -O back to -O1 again.
Reviewed By: echristo, dexonsmith, arphaman
Differential Revision: https://reviews.llvm.org/D79916
After a first attempt to fix the test-suite failures, my first recommit
caused the same failures again. I had updated CMakeList.txt files of
tests that needed -fcommon, but it turns out that there are also
Makefiles which are used by some bots, so I've updated these Makefiles
now too.
See the original commit message for more details on this change:
0a9fc9233e
This includes fixes for:
- test-suite: some benchmarks need to be compiled with -fcommon, see D75557.
- compiler-rt: one test needed -fcommon, and another a change, see D75520.
This reverts commit 0a9fc9233e.
Going to look at the asan failures.
I find the failures in the test suite weird, because they look
like compile time test and I don't understand how that can be
failing, but will have a brief look at that too.
This makes -fno-common the default for all targets because this has performance
and code-size benefits and is more language conforming for C code.
Additionally, GCC10 also defaults to -fno-common and so we get consistent
behaviour with GCC.
With this change, C code that uses tentative definitions as definitions of a
variable in multiple translation units will trigger multiple-definition linker
errors. Generally, this occurs when the use of the extern keyword is neglected
in the declaration of a variable in a header file. In some cases, no specific
translation unit provides a definition of the variable. The previous behavior
can be restored by specifying -fcommon.
As GCC has switched already, we benefit from applications already being ported
and existing documentation how to do this. For example:
- https://gcc.gnu.org/gcc-10/porting_to.html
- https://wiki.gentoo.org/wiki/Gcc_10_porting_notes/fno_common
Differential revision: https://reviews.llvm.org/D75056
Similar to the rest of the command line that is recorded, the program
path must also have spaces and backslashes escaped. Without this
parsing the recorded command line becomes hard on platforms like
Windows where spaces and backslashes are common.
This was originally reverted in
577d9ce35532439203411c999deefc9c80e04c69; this version makes a test
agnostic to the presence of backslashes in paths on some platforms.
Patch By: Ravi Ramaseshan
Differential Revision: https://reviews.llvm.org/D74811
Similar to the rest of the command line that is recorded, the program
path must also have spaces and backslashes escaped. Without this
parsing the recorded command line becomes hard on platforms like
Windows where spaces and backslashes are common.
Patch By: Ravi Ramaseshan
Differential Revision: https://reviews.llvm.org/D74811
First attempt at implementing -fsemantic-interposition.
Rely on GlobalValue::isInterposable that already captures most of the expected
behavior.
Rely on a ModuleFlag to state whether we should respect SemanticInterposition or
not. The default remains no.
So this should be a no-op if -fsemantic-interposition isn't used, and if it is,
isInterposable being already used in most optimisation, they should honor it
properly.
Note that it only impacts architecture compiled with -fPIC and no pie.
Differential Revision: https://reviews.llvm.org/D72829
With this patch, the clang tool will now call the -cc1 invocation directly inside the same process. Previously, the -cc1 invocation was creating, and waiting for, a new process.
This patch therefore reduces the number of created processes during a build, thus it reduces build times on platforms where process creation can be costly (Windows) and/or impacted by a antivirus.
It also makes debugging a bit easier, as there's no need to attach to the secondary -cc1 process anymore, breakpoints will be hit inside the same process.
Crashes or signaling inside the -cc1 invocation will have the same side-effect as before, and will be reported through the same means.
This behavior can be controlled at compile-time through the CLANG_SPAWN_CC1 cmake flag, which defaults to OFF. Setting it to ON will revert to the previous behavior, where any -cc1 invocation will create/fork a secondary process.
At run-time, it is also possible to tweak the CLANG_SPAWN_CC1 environment variable. Setting it and will override the compile-time setting. A value of 0 calls -cc1 inside the calling process; a value of 1 will create a secondary process, as before.
Differential Revision: https://reviews.llvm.org/D69825
All 130+ f_Group flags that take an argument allow it after a '=',
except for fdebug-complation-dir. Add a Joined<> alias so that
it behaves consistently with all the other f_Group flags.
(Keep the old Separate flag for backwards compat.)
Our build system does not handle randomly named files created during
the build well. We'd prefer to write compilation output directly
without creating a temporary file. Function parameters already
existed to control this behavior but were not exposed all the way out
to the command line.
Patch by Zachary Henkel!
Differential revision: https://reviews.llvm.org/D70615
Patch was reverted because https://bugs.llvm.org/show_bug.cgi?id=44048
The original patch is modified to set the strictfp IR attribute
explicitly in CodeGen instead of as a side effect of IRBuilder.
In the 2nd attempt to reapply there was a windows lit test fail, the
tests were fixed to use wildcard matching.
Differential Revision: https://reviews.llvm.org/D62731
and a follow-up NFC rearrangement as it's causing a crash on valid. Testcase is on the original review thread.
This reverts commits af57dbf12e and e6584b2b7b
Add options to control floating point behavior: trapping and
exception behavior, rounding, and control of optimizations that affect
floating point calculations. More details in UsersManual.rst.
Reviewers: rjmccall
Differential Revision: https://reviews.llvm.org/D62731
Use a tri-state enum to represent shouldUseFramePointer() and
shouldUseLeafFramePointer().
This simplifies the logic and fixes PR9825:
-fno-omit-frame-pointer doesn't imply -mno-omit-leaf-frame-pointer.
and PR24003:
/Oy- /O2 should not omit leaf frame pointer: this matches MSVC x86-32.
(/Oy- is a no-op on MSVC x86-64.)
and:
when CC1 option -mdisable-fp-elim if absent, -momit-leaf-frame-pointer
can also be omitted.
The new behavior matches GCC:
-fomit-frame-pointer wins over -mno-omit-leaf-frame-pointer
-fno-omit-frame-pointer loses out to -momit-leaf-frame-pointer
The behavior makes lots of sense. We have 4 states:
- 00) leaf retained, non-leaf retained
- 01) leaf retained, non-leaf omitted (this is invalid)
- 10) leaf omitted, non-leaf retained (what -momit-leaf-frame-pointer was designed for)
- 11) leaf omitted, non-leaf omitted
"omit" options taking precedence over "no-omit" options is the only way
to make 3 valid states representable with -f(no-)?omit-frame-pointer and
-m(no-)?omit-leaf-pointer.
Reviewed By: ychen
Differential Revision: https://reviews.llvm.org/D64294
llvm-svn: 365860
The flag is useful when wanting to create .o files that are independent
from the absolute path to the build directory. -fdebug-prefix-map= can
be used to the same effect, but it requires putting the absolute path
to the build directory on the build command line, so it still requires
the build command line to be dependent on the absolute path of the build
directory. With this flag, "-fdebug-compilation-dir ." makes it so that
both debug info and the compile command itself are independent of the
absolute path of the build directory, which is good for build
determinism (in the sense that the build is independent of which
directory it happens in) and for caching compile results.
(The tradeoff is that the debugger needs explicit configuration to know
the build directory. See also http://dwarfstd.org/ShowIssue.php?issue=171130.2)
Differential Revision: https://reviews.llvm.org/D63387
llvm-svn: 363548
When -forder-file-instrumentation is on, we pass llvm flag to enable the order file instrumentation pass.
https://reviews.llvm.org/D58751
llvm-svn: 355333
Summary:
Add an option to initialize automatic variables with either a pattern or with
zeroes. The default is still that automatic variables are uninitialized. Also
add attributes to request uninitialized on a per-variable basis, mainly to disable
initialization of large stack arrays when deemed too expensive.
This isn't meant to change the semantics of C and C++. Rather, it's meant to be
a last-resort when programmers inadvertently have some undefined behavior in
their code. This patch aims to make undefined behavior hurt less, which
security-minded people will be very happy about. Notably, this means that
there's no inadvertent information leak when:
- The compiler re-uses stack slots, and a value is used uninitialized.
- The compiler re-uses a register, and a value is used uninitialized.
- Stack structs / arrays / unions with padding are copied.
This patch only addresses stack and register information leaks. There's many
more infoleaks that we could address, and much more undefined behavior that
could be tamed. Let's keep this patch focused, and I'm happy to address related
issues elsewhere.
To keep the patch simple, only some `undef` is removed for now, see
`replaceUndef`. The padding-related infoleaks are therefore not all gone yet.
This will be addressed in a follow-up, mainly because addressing padding-related
leaks should be a stand-alone option which is implied by variable
initialization.
There are three options when it comes to automatic variable initialization:
0. Uninitialized
This is C and C++'s default. It's not changing. Depending on code
generation, a programmer who runs into undefined behavior by using an
uninialized automatic variable may observe any previous value (including
program secrets), or any value which the compiler saw fit to materialize on
the stack or in a register (this could be to synthesize an immediate, to
refer to code or data locations, to generate cookies, etc).
1. Pattern initialization
This is the recommended initialization approach. Pattern initialization's
goal is to initialize automatic variables with values which will likely
transform logic bugs into crashes down the line, are easily recognizable in
a crash dump, without being values which programmers can rely on for useful
program semantics. At the same time, pattern initialization tries to
generate code which will optimize well. You'll find the following details in
`patternFor`:
- Integers are initialized with repeated 0xAA bytes (infinite scream).
- Vectors of integers are also initialized with infinite scream.
- Pointers are initialized with infinite scream on 64-bit platforms because
it's an unmappable pointer value on architectures I'm aware of. Pointers
are initialize to 0x000000AA (small scream) on 32-bit platforms because
32-bit platforms don't consistently offer unmappable pages. When they do
it's usually the zero page. As people try this out, I expect that we'll
want to allow different platforms to customize this, let's do so later.
- Vectors of pointers are initialized the same way pointers are.
- Floating point values and vectors are initialized with a negative quiet
NaN with repeated 0xFF payload (e.g. 0xffffffff and 0xffffffffffffffff).
NaNs are nice (here, anways) because they propagate on arithmetic, making
it more likely that entire computations become NaN when a single
uninitialized value sneaks in.
- Arrays are initialized to their homogeneous elements' initialization
value, repeated. Stack-based Variable-Length Arrays (VLAs) are
runtime-initialized to the allocated size (no effort is made for negative
size, but zero-sized VLAs are untouched even if technically undefined).
- Structs are initialized to their heterogeneous element's initialization
values. Zero-size structs are initialized as 0xAA since they're allocated
a single byte.
- Unions are initialized using the initialization for the largest member of
the union.
Expect the values used for pattern initialization to change over time, as we
refine heuristics (both for performance and security). The goal is truly to
avoid injecting semantics into undefined behavior, and we should be
comfortable changing these values when there's a worthwhile point in doing
so.
Why so much infinite scream? Repeated byte patterns tend to be easy to
synthesize on most architectures, and otherwise memset is usually very
efficient. For values which aren't entirely repeated byte patterns, LLVM
will often generate code which does memset + a few stores.
2. Zero initialization
Zero initialize all values. This has the unfortunate side-effect of
providing semantics to otherwise undefined behavior, programs therefore
might start to rely on this behavior, and that's sad. However, some
programmers believe that pattern initialization is too expensive for them,
and data might show that they're right. The only way to make these
programmers wrong is to offer zero-initialization as an option, figure out
where they are right, and optimize the compiler into submission. Until the
compiler provides acceptable performance for all security-minded code, zero
initialization is a useful (if blunt) tool.
I've been asked for a fourth initialization option: user-provided byte value.
This might be useful, and can easily be added later.
Why is an out-of band initialization mecanism desired? We could instead use
-Wuninitialized! Indeed we could, but then we're forcing the programmer to
provide semantics for something which doesn't actually have any (it's
uninitialized!). It's then unclear whether `int derp = 0;` lends meaning to `0`,
or whether it's just there to shut that warning up. It's also way easier to use
a compiler flag than it is to manually and intelligently initialize all values
in a program.
Why not just rely on static analysis? Because it cannot reason about all dynamic
code paths effectively, and it has false positives. It's a great tool, could get
even better, but it's simply incapable of catching all uses of uninitialized
values.
Why not just rely on memory sanitizer? Because it's not universally available,
has a 3x performance cost, and shouldn't be deployed in production. Again, it's
a great tool, it'll find the dynamic uses of uninitialized variables that your
test coverage hits, but it won't find the ones that you encounter in production.
What's the performance like? Not too bad! Previous publications [0] have cited
2.7 to 4.5% averages. We've commmitted a few patches over the last few months to
address specific regressions, both in code size and performance. In all cases,
the optimizations are generally useful, but variable initialization benefits
from them a lot more than regular code does. We've got a handful of other
optimizations in mind, but the code is in good enough shape and has found enough
latent issues that it's a good time to get the change reviewed, checked in, and
have others kick the tires. We'll continue reducing overheads as we try this out
on diverse codebases.
Is it a good idea? Security-minded folks think so, and apparently so does the
Microsoft Visual Studio team [1] who say "Between 2017 and mid 2018, this
feature would have killed 49 MSRC cases that involved uninitialized struct data
leaking across a trust boundary. It would have also mitigated a number of bugs
involving uninitialized struct data being used directly.". They seem to use pure
zero initialization, and claim to have taken the overheads down to within noise.
Don't just trust Microsoft though, here's another relevant person asking for
this [2]. It's been proposed for GCC [3] and LLVM [4] before.
What are the caveats? A few!
- Variables declared in unreachable code, and used later, aren't initialized.
This goto, Duff's device, other objectionable uses of switch. This should
instead be a hard-error in any serious codebase.
- Volatile stack variables are still weird. That's pre-existing, it's really
the language's fault and this patch keeps it weird. We should deprecate
volatile [5].
- As noted above, padding isn't fully handled yet.
I don't think these caveats make the patch untenable because they can be
addressed separately.
Should this be on by default? Maybe, in some circumstances. It's a conversation
we can have when we've tried it out sufficiently, and we're confident that we've
eliminated enough of the overheads that most codebases would want to opt-in.
Let's keep our precious undefined behavior until that point in time.
How do I use it:
1. On the command-line:
-ftrivial-auto-var-init=uninitialized (the default)
-ftrivial-auto-var-init=pattern
-ftrivial-auto-var-init=zero -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
2. Using an attribute:
int dont_initialize_me __attribute((uninitialized));
[0]: https://users.elis.ugent.be/~jsartor/researchDocs/OOPSLA2011Zero-submit.pdf
[1]: https://twitter.com/JosephBialek/status/1062774315098112001
[2]: https://outflux.net/slides/2018/lss/danger.pdf
[3]: https://gcc.gnu.org/ml/gcc-patches/2014-06/msg00615.html
[4]: 776a0955ef
[5]: http://wg21.link/p1152
I've also posted an RFC to cfe-dev: http://lists.llvm.org/pipermail/cfe-dev/2018-November/060172.html
<rdar://problem/39131435>
Reviewers: pcc, kcc, rsmith
Subscribers: JDevlieghere, jkorous, dexonsmith, cfe-commits
Differential Revision: https://reviews.llvm.org/D54604
llvm-svn: 349442
Implement options in clang to enable recording the driver command-line
in an ELF section.
Implement a new special named metadata, llvm.commandline, to support
frontends embedding their command-line options in IR/ASM/ELF.
This differs from the GCC implementation in some key ways:
* In GCC there is only one command-line possible per compilation-unit,
in LLVM it mirrors llvm.ident and multiple are allowed.
* In GCC individual options are separated by NULL bytes, in LLVM entire
command-lines are separated by NULL bytes. The advantage of the GCC
approach is to clearly delineate options in the face of embedded
spaces. The advantage of the LLVM approach is to support merging
multiple command-lines unambiguously, while handling embedded spaces
with escaping.
Differential Revision: https://reviews.llvm.org/D54487
Clang Differential Revision: https://reviews.llvm.org/D54489
llvm-svn: 349155
Summary:
Linux toolchain accidentally added "-u__llvm_runtime_variable" when "-fprofile-arcs -ftest-coverage", this is not added when "--coverage" option is used.
Using "-u__llvm_runtime_variable" generates an empty default.profraw file while an application built with "-fprofile-arcs -ftest-coverage" is running.
Reviewers: calixte, marco-c, sylvestre.ledru
Reviewed By: marco-c
Subscribers: vsk, cfe-commits
Differential Revision: https://reviews.llvm.org/D54195
llvm-svn: 347677
This can be used to preserve profiling information across codebase
changes that have widespread impact on mangled names, but across which
most profiling data should still be usable. For example, when switching
from libstdc++ to libc++, or from the old libstdc++ ABI to the new ABI,
or even from a 32-bit to a 64-bit build.
The user can provide a remapping file specifying parts of mangled names
that should be treated as equivalent (eg, std::__1 should be treated as
equivalent to std::__cxx11), and profile data will be treated as
applying to a particular function if its name is equivalent to the name
of a function in the profile data under the provided equivalences. See
the documentation change for a description of how this is configured.
Remapping is supported for both sample-based profiling and instruction
profiling. We do not support remapping indirect branch target
information, but all other profile data should be remapped
appropriately.
Support is only added for the new pass manager. If someone wants to also
add support for this for the old pass manager, doing so should be
straightforward.
llvm-svn: 344199
Summary:
Previously, any instance of -fomit-frame-pointer would make it such that
-pg was an invalid flag combination. If -fno-omit-frame-pointer is
passed later on the command line (such that it actually takes effect),
-pg should be allowed.
Reviewers: nickdesaulniers
Reviewed By: nickdesaulniers
Subscribers: manojgupta, nickdesaulniers, cfe-commits, kongyi, chh, pirama
Differential Revision: https://reviews.llvm.org/D51713
llvm-svn: 342165
Summary:
Support for this option is needed for building Linux kernel.
This is a very frequently requested feature by kernel developers.
More details : https://lkml.org/lkml/2018/4/4/601
GCC option description for -fdelete-null-pointer-checks:
This Assume that programs cannot safely dereference null pointers,
and that no code or data element resides at address zero.
-fno-delete-null-pointer-checks is the inverse of this implying that
null pointer dereferencing is not undefined.
This feature is implemented in as the function attribute
"null-pointer-is-valid"="true".
This CL only adds the attribute on the function.
It also strips "nonnull" attributes from function arguments but
keeps the related warnings unchanged.
Corresponding LLVM change rL336613 already updated the
optimizations to not treat null pointer dereferencing
as undefined if the attribute is present.
Reviewers: t.p.northover, efriedma, jyknight, chandlerc, rnk, srhines, void, george.burgess.iv
Reviewed By: jyknight
Subscribers: drinkcat, xbolva00, cfe-commits
Differential Revision: https://reviews.llvm.org/D47894
llvm-svn: 337433
This implements support for the previously ignored flag
`-falign-functions`. This allows the frontend to request alignment on
function definitions in the translation unit where they are not
explicitly requested in code. This is compatible with the GCC behaviour
and the ICC behaviour.
The scalar value passed to `-falign-functions` aligns functions to a
power-of-two boundary. If flag is used, the functions are aligned to
16-byte boundaries. If the scalar is specified, it must be an integer
less than or equal to 4096. If the value is not a power-of-two, the
driver will round it up to the nearest power of two.
llvm-svn: 330378
Summary:
"-fmerge-all-constants" is a non-conforming optimization and should not
be the default. It is also causing miscompiles when building Linux
Kernel (https://lkml.org/lkml/2018/3/20/872).
Fixes PR18538.
Reviewers: rjmccall, rsmith, chandlerc
Reviewed By: rsmith, chandlerc
Subscribers: srhines, cfe-commits
Differential Revision: https://reviews.llvm.org/D45289
llvm-svn: 329300
Summary:
Currently, assertion-disabled Clang builds emit value names when generating LLVM IR. This is controlled by the `NDEBUG` macro, and is not easily overridable. In order to get IR output containing names from a release build of Clang, the user must manually construct the CC1 invocation w/o the `-discard-value-names` option. This is less than ideal.
For example, Godbolt uses a release build of Clang, and so when asked to emit LLVM IR the result lacks names, making it harder to read. Manually invoking CC1 on Compiler Explorer is not feasible.
This patch adds the driver options `-fdiscard-value-names` and `-fno-discard-value-names` which allow the user to override the default behavior. If neither is specified, the old behavior remains.
Reviewers: erichkeane, aaron.ballman, lebedev.ri
Reviewed By: aaron.ballman
Subscribers: bogner, cfe-commits
Differential Revision: https://reviews.llvm.org/D42887
llvm-svn: 324498
Cf-protection is a target independent flag that instructs the back-end to instrument control flow mechanisms like: Branch, Return, etc.
For example in X86 this flag will be used to instrument Indirect Branch Tracking instructions.
Differential Revision: https://reviews.llvm.org/D40478
Change-Id: I5126e766c0e6b84118cae0ee8a20fe78cc373dea
llvm-svn: 322063
Move the logic for determining the `wchar_t` type information into the
driver. Rather than passing the single bit of information of
`-fshort-wchar` indicate to the frontend the desired type of `wchar_t`
through a new `-cc1` option of `-fwchar-type` and indicate the
signedness through `-f{,no-}signed-wchar`. This replicates the current
logic which was spread throughout Basic into the
`RenderCharacterOptions`.
Most of the changes to the tests are to ensure that the frontend uses
the correct type. Add a new test set under `test/Driver/wchar_t.c` to
ensure that we calculate the proper types for the various cases.
llvm-svn: 315126
Summary: With accurate sample profile, we can do more aggressive size optimization. For some size-critical application, this can reduce the text size by 20%
Reviewers: davidxl, rsmith
Reviewed By: davidxl, rsmith
Subscribers: mehdi_amini, eraman, sanjoy, cfe-commits
Differential Revision: https://reviews.llvm.org/D37091
llvm-svn: 311707
-fslp-vectorize-aggressive and -fno-slp-vectorize-aggressive flags back
under this group and test for the warning. Document the future removal
in the ReleaseNotes.
Differential Revision: https://reviews.llvm.org/D34926
llvm-svn: 306965
basic block vectorizer. This vectorizer has had no known users for many,
many years and is completely surpassed by the normal
'-fvectorize-slp'-controlled SLP vectorizer in LLVM.
Hal proposed this back in 2014 to no objections:
http://lists.llvm.org/pipermail/llvm-dev/2014-November/079091.html
While this patch completely removes the flag, Joerg is working on
a patch that will add it back in a way that warns users and ignores the
flag in a clear and well factored way (so that we can keep doing this
going forward).
Differential Revision: https://reviews.llvm.org/D34846
llvm-svn: 306786
This is recommit of r302775, reverted in r302777 due to a fail in
clang-tidy. Original mesage is below.
Now if clang driver is given wrong arguments, in some cases it
continues execution and returns zero code. This change fixes this
behavior.
The fix revealed some errors in clang test set.
File test/Driver/gfortran.f90 added in r118203 checks forwarding
gfortran flags to GCC. Now driver reports error on this file, because
the option -working-directory implemented in clang differs from the
option with the same name implemented in gfortran, in clang the option
requires argument, in gfortran does not.
In the file test/Driver/arm-darwin-builtin.c clang is called with
options -fbuiltin-strcat and -fbuiltin-strcpy. These option were removed
in r191435 and now clang reports error on this test.
File arm-default-build-attributes.s uses option -verify, which is not
supported by driver, it is cc1 option.
Similarly, the file split-debug.h uses options -fmodules-embed-all-files
and -fmodule-format=obj, which are not supported by driver.
Other revealed errors are mainly mistypes.
Differential Revision: https://reviews.llvm.org/D33013
llvm-svn: 303756
Now if clang driver is given wrong arguments, in some cases it
continues execution and returns zero code. This change fixes this
behavior.
The fix revealed some errors in clang test set.
File test/Driver/gfortran.f90 added in r118203 checks forwarding
gfortran flags to GCC. Now driver reports error on this file, because
the option -working-directory implemented in clang differs from the
option with the same name implemented in gfortran, in clang the option
requires argument, in gfortran does not.
In the file test/Driver/arm-darwin-builtin.c clang is called with
options -fbuiltin-strcat and -fbuiltin-strcpy. These option were removed
in r191435 and now clang reports error on this test.
File arm-default-build-attributes.s uses option -verify, which is not
supported by driver, it is cc1 option.
Similarly, the file split-debug.h uses options -fmodules-embed-all-files
and -fmodule-format=obj, which are not supported by driver.
Other revealed errors are mainly mistypes.
Differential Revision: https://reviews.llvm.org/D33013
llvm-svn: 302775
This commit teaches Clang to recognize editor placeholders that are produced
when an IDE like Xcode inserts a code-completion result that includes a
placeholder. Now when the lexer sees a placeholder token, it emits an
'editor placeholder in source file' error and creates an identifier token
that represents the placeholder. The parser/sema can now recognize the
placeholders and can suppress the diagnostics related to the placeholders. This
ensures that live issues in an IDE like Xcode won't get spurious diagnostics
related to placeholders.
This commit also adds a new compiler option named '-fallow-editor-placeholders'
that silences the 'editor placeholder in source file' error. This is useful
for an IDE like Xcode as we don't want to display those errors in live issues.
rdar://31581400
Differential Revision: https://reviews.llvm.org/D32081
llvm-svn: 300667
Summary: We need to be able to disable samplepgo for specific files by supporting -fno-auto-profile and -fno-profile-sample-use
Reviewers: davidxl, dnovillo, echristo
Reviewed By: echristo
Subscribers: echristo, cfe-commits
Differential Revision: https://reviews.llvm.org/D31213
llvm-svn: 298446
Jian Cai