Summary:
As discussed in [[ https://bugs.llvm.org/show_bug.cgi?id=38166 | PR38166 ]], we need to be able to distinqush whether the cast
we are visiting is actually a cast, or part of an `ExplicitCast`.
There are at least four ways to get there:
1. Introduce a new `CastKind`, and use it instead of `IntegralCast` if we are in `ExplicitCast`.
Would work, but does not scale - what if we will need more of these cast kinds?
2. Introduce a flag in `CastExprBits`, whether this cast is part of `ExplicitCast` or not.
Would work, but it isn't immediately clear where it needs to be set.
2. Fix `ScalarExprEmitter::VisitCastExpr()` to visit these `NoOp` casts.
As pointed out by @rsmith, CodeGenFunction::EmitMaterializeTemporaryExpr calls
skipRValueSubobjectAdjustments, which steps over the CK_NoOp cast`,
which explains why we currently don't visit those.
This is probably impossible, as @efriedma points out, that is intentional as per `[class.temporary]` in the standard
3. And the simplest one, just record which NoOp casts we skip.
It just kinda works as-is afterwards.
But, the approach with a flag is the least intrusive one, and is probably the best one overall.
Reviewers: rsmith, rjmccall, majnemer, efriedma
Reviewed By: rsmith
Subscribers: cfe-commits, aaron.ballman, vsk, llvm-commits, rsmith
Differential Revision: https://reviews.llvm.org/D49508
llvm-svn: 337815
As documented here: https://software.intel.com/en-us/node/682969 and
https://software.intel.com/en-us/node/523346. cpu_dispatch multiversioning
is an ICC feature that provides for function multiversioning.
This feature is implemented with two attributes: First, cpu_specific,
which specifies the individual function versions. Second, cpu_dispatch,
which specifies the location of the resolver function and the list of
resolvable functions.
This is valuable since it provides a mechanism where the resolver's TU
can be specified in one location, and the individual implementions
each in their own translation units.
The goal of this patch is to be source-compatible with ICC, so this
implementation diverges from the ICC implementation in a few ways:
1- Linux x86/64 only: This implementation uses ifuncs in order to
properly dispatch functions. This is is a valuable performance benefit
over the ICC implementation. A future patch will be provided to enable
this feature on Windows, but it will obviously more closely fit ICC's
implementation.
2- CPU Identification functions: ICC uses a set of custom functions to identify
the feature list of the host processor. This patch uses the cpu_supports
functionality in order to better align with 'target' multiversioning.
1- cpu_dispatch function def/decl: ICC's cpu_dispatch requires that the function
marked cpu_dispatch be an empty definition. This patch supports that as well,
however declarations are also permitted, since the linker will solve the
issue of multiple emissions.
Differential Revision: https://reviews.llvm.org/D47474
llvm-svn: 337552
This diagnoses calls to memset that have the second and third arguments
transposed, for example:
memset(buf, sizeof(buf), 0);
This is done by checking if the third argument is a literal 0, or if the second
is a sizeof expression (and the third isn't). The first check is also done for
calls to bzero.
Differential revision: https://reviews.llvm.org/D49112
llvm-svn: 337470
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
The "casts away constness" check doesn't care at all how the different
layers of the source and destination type were formed: for example, if
the source is a pointer and the destination is a pointer-to-member, the
types are still decomposed and their pointee qualifications are still
checked.
This rule is bizarre and somewhat ridiculous, so as an extension we
accept code making use of such reinterpret_casts with a warning outside
of SFINAE contexts.
llvm-svn: 336738
This is part of an ongoing attempt at making 512 bit vectors illegal in the X86 backend type legalizer due to CPU frequency penalties associated with wide vectors on Skylake Server CPUs. We want the loop vectorizer to be able to emit IR containing wide vectors as intermediate operations in vectorized code and allow these wide vectors to be legalized to 256 bits by the X86 backend even though we are targetting a CPU that supports 512 bit vectors. This is similar to what happens with an AVX2 CPU, the vectorizer can emit wide vectors and the backend will split them. We want this splitting behavior, but still be able to use new Skylake instructions that work on 256-bit vectors and support things like masking and gather/scatter.
Of course if the user uses explicit vector code in their source code we need to not split those operations. Especially if they have used any of the 512-bit vector intrinsics from immintrin.h. And we need to make it so that merely using the intrinsics produces the expected code in order to be backwards compatible.
To support this goal, this patch adds a new IR function attribute "min-legal-vector-width" that can indicate the need for a minimum vector width to be legal in the backend. We need to ensure this attribute is set to the largest vector width needed by any intrinsics from immintrin.h that the function uses. The inliner will be reponsible for merging this attribute when a function is inlined. We may also need a way to limit inlining in the future as well, but we can discuss that in the future.
To make things more complicated, there are two different ways intrinsics are implemented in immintrin.h. Either as an always_inline function containing calls to builtins(can be target specific or target independent) or vector extension code. Or as a macro wrapper around a taget specific builtin. I believe I've removed all cases where the macro was around a target independent builtin.
To support the always_inline function case this patch adds attribute((min_vector_width(128))) that can be used to tag these functions with their vector width. All x86 intrinsic functions that operate on vectors have been tagged with this attribute.
To support the macro case, all x86 specific builtins have also been tagged with the vector width that they require. Use of any builtin with this property will implicitly increase the min_vector_width of the function that calls it. I've done this as a new property in the attribute string for the builtin rather than basing it on the type string so that we can opt into it on a per builtin basis and avoid any impact to target independent builtins.
There will be future work to support vectors passed as function arguments and supporting inline assembly. And whatever else we can find that isn't covered by this patch.
Special thanks to Chandler who suggested this direction and reviewed a preview version of this patch. And thanks to Eric Christopher who has had many conversations with me about this issue.
Differential Revision: https://reviews.llvm.org/D48617
llvm-svn: 336583
If a function has multiple format_arg attributes, clang only considers
the first it finds (because AttributeLists are in reverse order, not
necessarily the textually first) and ignores all others.
Loop over all FormatArgAttr to print warnings for all declared
format_arg attributes.
For instance, libintl's ngettext (select plural or singular version of
format string) has two __format_arg__ attributes.
Differential Revision: https://reviews.llvm.org/D48734
llvm-svn: 336239
NumTypos guard value ~0U doesn't prevent from creating new delayed typos. When
you create new delayed typos during typo correction, value ~0U wraps around to
0. When NumTypos is 0 we can miss some typos and treat an expression as it can
be typo-corrected. But if the expression is still invalid after correction, we
can get stuck in infinite loop trying to correct it.
Fix by not using value ~0U so that NumTypos correctly reflects the number of
typos.
rdar://problem/38642201
Reviewers: arphaman, majnemer, rsmith
Reviewed By: rsmith
Subscribers: rsmith, nicholas, cfe-commits
Differential Revision: https://reviews.llvm.org/D47341
llvm-svn: 335638
dead code.
This is important for C++ templates that essentially compute the valid
input in a way that is constant and will cause all the invalid cases to
be dead code that is deleted. Code in the wild actually does this and
GCC also accepts these kinds of patterns so it is important to support
it.
To make this work, we provide a non-error path to diagnose these issues,
and use a default-error warning instead. This keeps the relatively
strict handling but prevents nastiness like SFINAE on these errors. It
also allows us to safely use the system to diagnose this only when it
occurs at runtime (in emitted code).
Entertainingly, this required fixing the syntax in various other ways
for the x86 test because we never bothered to diagnose that the returns
were invalid.
Since debugging these compile failures was super confusing, I've also
improved the diagnostic to actually say what the value was. Most of the
checks I've made ignore this to simplify maintenance, but I've checked
it in a few places to make sure the diagnsotic is working.
Depends on D48462. Without that, we might actually crash some part of
the compiler after bypassing the error here.
Thanks to Richard, Ben Kramer, and especially Craig Topper for all the
help here.
Differential Revision: https://reviews.llvm.org/D48464
llvm-svn: 335309
Summary:
The comment with the OpenCL clause about this clearly
says: "No type shall be qualified by qualifiers for
two or more different address spaces."
This must mean that two or more qualifiers for the
_same_ address space is allowed. However, it is
likely unintended by the programmer, so emit a
warning.
For dependent address space types, reject them like
before since we cannot know what the address space
will be.
Patch by Bevin Hansson (ebevhan).
Reviewers: Anastasia
Reviewed By: Anastasia
Subscribers: bader, cfe-commits
Differential Revision: https://reviews.llvm.org/D47630
llvm-svn: 335103
... instead of prepending it at the beginning (the original behavior
since implemented in r122535 2010-12-23). This builds up an
AttributeList in the the order in which the attributes appear in the
source.
The reverse order caused nodes for attributes in the AST (e.g. LoopHint)
to be in the reverse, and therefore printed in the wrong order by
-ast-dump. Some TODO comments mention this. The order was explicitly
reversed for enable_if attribute overload resolution and name mangling,
which is not necessary anymore with this patch.
The change unfortunately has some secondary effects, especially for
diagnostic output. In the simplest cases, the CHECK lines or expected
diagnostic were changed to the the new output. If the kind of
error/warning changed, the attribute's order was changed instead.
It also causes some 'previous occurrence here' hints to be textually
after the main marker. This typically happens when attributes are
merged, but are incompatible. Interchanging the role of the the main
and note SourceLocation will also cause the case where two different
declaration's attributes (in contrast to multiple attributes of the
same declaration) are merged to be reversed. There is no easy fix
because sometimes previous attributes are merged into a new
declaration's attribute list, sometimes new attributes are added to a
previous declaration's attribute list. Since 'previous occurrence here'
pointing to locations after the main marker is not rare, I left the
markers as-is; it is only relevant when the attributes are declared in
the same declaration anyway, which often is on the same line.
Differential Revision: https://reviews.llvm.org/D48100
llvm-svn: 335084
r242675 changed the signature for the signbit builtin but did not introduce proper semantic checking to ensure the arguments are as-expected. This patch groups the signbit builtin along with the other fp classification builtins. Fixes PR28172.
llvm-svn: 335050
r242675 changed the signature for the signbit builtin but did not introduce proper semantic checking to ensure the arguments are as-expected. This patch groups the signbit builtin along with the other fp classification builtins. Fixes PR28172.
llvm-svn: 335048
Diasble the use of the type __float128 for PPC machines older
than Power9.
The use of -mfloat128 for PPC machine older than Power9 will result
in an error.
Differential Revision: https://reviews.llvm.org/D48088
llvm-svn: 334613
Summary:
This fixes the ranges for the vcvth family of FP16 intrinsics in the clang front end. Previously it was accepting incorrect ranges
-Changed builtin range checking in SemaChecking
-added tests SemaCheck changes - included in their own file since no similar one exists
-modified existing tests to reflect new ranges
Reviewers: SjoerdMeijer, javed.absar
Reviewed By: SjoerdMeijer
Subscribers: kristof.beyls, cfe-commits
Differential Revision: https://reviews.llvm.org/D47592
llvm-svn: 334489
Adds support for these intrinsics, which are ARM and ARM64 only:
_interlockedbittestandreset_acq
_interlockedbittestandreset_rel
_interlockedbittestandreset_nf
_interlockedbittestandset_acq
_interlockedbittestandset_rel
_interlockedbittestandset_nf
Refactor the bittest intrinsic handling to decompose each intrinsic into
its action, its width, and its atomicity.
llvm-svn: 334239
For pointer assignments of VLA types, Clang currently detects when array
dimensions _lower_ than a variable dimension differ, and reports a warning.
However it does not do the same when the _higher_ dimensions differ, a
case that GCC does catch.
These two pointer types
int (*foo)[1][bar][3];
int (*baz)[1][2][3];
are compatible with each another, and the program is well formed if
bar == 2, a matter that is the programmers problem. However the following:
int (*qux)[2][2][3];
would not be compatible with either, because the upper dimension differs
in size. Clang reports baz is incompatible with qux, but not that foo is
incompatible with qux because it doesn't check those higher dimensions.
Fix this by comparing array sizes on higher dimensions: if both are
constants but unequal then report incompatibility; if either dimension is
variable then we can't know either way.
Differential Revision: https://reviews.llvm.org/D47628
llvm-svn: 333989
I think this is a holdover from when we used to declare variables inside the macros. And then its been copy and pasted forward for years every time a new macro intrinsic gets added.
Interestingly this caused some tests for IRGen to be slightly more optimized. We now return a zeroinitializer directly instead of going through a store+load.
It also removed a bogus error message on another test.
llvm-svn: 333613
For example, given:
enum __attribute__((deprecated)) T *p;
-ast-print produced:
enum T *p;
The attribute was lost because the enum forward decl was lost.
Another example is the loss of enum forward decls from C++ namespaces
(in MS compatibility mode).
The trouble was that the EnumDecl node was suppressed, as revealed by
-ast-dump. The suppression of the EnumDecl was intentional in
r116122, but I don't understand why. The suppression isn't needed for
the test suite to behave.
Reviewed by: rsmith
Differential Revision: https://reviews.llvm.org/D46846
llvm-svn: 333574
This helps especially when the collision is for a template specialization,
where the template arguments are not available from anywhere else in the
diagnostic, and are likely relevant to the problem.
llvm-svn: 333489
Handling of the third parameter was only checking for *_n and not for the C11 variant, which means that cmpxchg of a 'desired' 0 value was erroneously warning. Handle C11 properly, and add extgensive tests for this as well as NULL pointers in a bunch of places.
Fixes r333246 from D47229.
llvm-svn: 333290
Summary:
As a companion to libc++ patch https://reviews.llvm.org/D47225, mark builtin atomic non-member functions which accept pointers as nonnull.
The atomic non-member functions accept pointers to std::atomic / std::atomic_flag as well as to the non-atomic value. These are all dereferenced unconditionally when lowered, and therefore will fault if null. It's a tiny gotcha for new users, especially when they pass in NULL as expected value (instead of passing a pointer to a NULL value).
<rdar://problem/18473124>
Reviewers: arphaman
Subscribers: aheejin, cfe-commits
Differential Revision: https://reviews.llvm.org/D47229
llvm-svn: 333246
unusual types.
Following the observed behavior of GCC, we now return -1 for vector types
(along with all of our extensions that GCC doesn't support), and for atomic
types we classify the underlying type.
GCC appears to have changed its classification for function and array arguments
between version 5 and version 6. Previously it would classify them as pointers
in C and as functions or arrays in C++, but from version 6 onwards, it
classifies them as pointers. We now follow the more recent GCC behavior rather
than emulating what I can only assume to be a historical bug in their C++
support for this builtin.
Finally, no version of GCC that I can find has ever used the "method"
classification for C++ pointers to member functions. Instead, GCC classifies
them as record types, presumably reflecting an internal implementation detail,
but whatever the reason we now produce compatible results.
llvm-svn: 333126
in gcc by https://gcc.gnu.org/ml/gcc-cvs/2018-04/msg00534.html.
The -mibt feature flag is being removed, and the -fcf-protection
option now also defines a CET macro and causes errors when used
on non-X86 targets, while X86 targets no longer check for -mibt
and -mshstk to determine if -fcf-protection is supported. -mshstk
is now used only to determine availability of shadow stack intrinsics.
Comes with an LLVM patch (D46882).
Patch by mike.dvoretsky
Differential Revision: https://reviews.llvm.org/D46881
llvm-svn: 332704
E. g. use "10.11" instead of "10_11".
We are maintaining backward compatibility by parsing underscore-delimited version tuples but no longer keep track of the separator and using dot format for output.
Differential Revision: https://reviews.llvm.org/D46747
rdar://problem/39845032
llvm-svn: 332598
For example, given:
struct T1 {
struct T2 *p0;
};
-ast-print produced:
struct T1 {
struct T2;
struct T2 *p0;
};
Compiling that produces a warning that the first struct T2 declaration
does not declare anything.
Details:
A tag decl group is one or more decls that share a type specifier that
is a tag decl (that is, a struct/union/class/enum decl). Within
functions, the parser builds such a tag decl group as part of a
DeclStmt. However, in decl contexts, such as file scope or a member
list, the parser does not group together the members of a tag decl
group. Previously, detection of tag decl groups during printing was
implemented but only if the tag decl was unnamed. Otherwise, as in
the above example, the members of the group did not print together and
so sometimes introduced warnings.
This patch extends detection of tag decl groups in decl contexts to
any tag decl that is recorded in the AST as not free-standing.
Reviewed by: rsmith
Differential Revision: https://reviews.llvm.org/D45465
llvm-svn: 332314
These intrinsics work exactly as all other atomic_fetch_* intrinsics and allow to create *atomicrmw* with ordering.
Updated the clang-extensions document.
Differential Revision: https://reviews.llvm.org/D46386
llvm-svn: 332193
Summary:
This attribute tells clang to skip this function from stack protector
when -stack-protector option is passed.
GCC option for this is:
__attribute__((__optimize__("no-stack-protector"))) and the
equivalent clang syntax would be: __attribute__((no_stack_protector))
This is used in Linux kernel to selectively disable stack protector
in certain functions.
Reviewers: aaron.ballman, rsmith, rnk, probinson
Reviewed By: aaron.ballman
Subscribers: probinson, srhines, cfe-commits
Differential Revision: https://reviews.llvm.org/D46300
llvm-svn: 331925
Summary:
The getConstraintRegister method is used by semantic checking of
inline assembly statements in order to diagnose conflicts between
clobber list and input/output lists. Currently ARM and AArch64 don't
override getConstraintRegister, so conflicts between registers
assigned to variables in asm labels and clobber lists are not
diagnosed. Such conflicts can cause assertion failures in the back end
and even miscompilations.
This patch implements getConstraintRegister for ARM and AArch64
targets. Since these targets don't have single-register constraints,
the implementation is trivial and just returns the register specified
in an asm label (if any).
Reviewers: eli.friedman, javed.absar, thopre
Reviewed By: thopre
Subscribers: rengolin, eraman, rogfer01, myatsina, kristof.beyls, cfe-commits, chrib
Differential Revision: https://reviews.llvm.org/D45965
llvm-svn: 331164
These builtins can't be handled by the backend on 64-bit targets. So error up front instead of throwing an isel error.
Fixes PR37225
Differential Revision: https://reviews.llvm.org/D46132
llvm-svn: 330987
For example, given:
void fn() {
enum __attribute__((deprecated)) T *p;
}
-ast-print produced:
void fn() {
enum T __attribute__((deprecated(""))) *p;
}
-ast-print on that produced:
void fn() {
enum T *p __attribute__((deprecated("")));
}
The attribute is on enum T in the first case, but it's on p in the
other cases.
Details:
Within enum declarations, enum attributes were always printed after
the tag and any member list. When no member list was present but the
enum was a type specifier in a variable declaration, the attribute
then applied to the variable not the enum, changing the semantics.
This patch fixes that by always printing attributes between the enum's
keyword and tag, as clang already does for structs, unions, and
classes.
Reviewed By: rsmith
Differential Revision: https://reviews.llvm.org/D45456
llvm-svn: 330722
As reported here: https://bugs.llvm.org/show_bug.cgi?id=37033
Any usage of a builtin function that uses a va_list by reference
will cause an assertion when redeclaring it.
After discussion in the review, it was concluded that the correct
way of accomplishing this fix is to make attempts to redeclare certain
builtins an error. Unfortunately, doing this limitation for all builtins
is likely a breaking change, so this commit simply limits it to
types with custom type checking and those that take a reference.
Two tests needed to be updated to make this work.
Differential Revision: https://reviews.llvm.org/D45383
llvm-svn: 330160
Found via codespell -q 3 -I ../clang-whitelist.txt
Where whitelist consists of:
archtype
cas
classs
checkk
compres
definit
frome
iff
inteval
ith
lod
methode
nd
optin
ot
pres
statics
te
thru
Patch by luzpaz! (This is a subset of D44188 that applies cleanly with a few
files that have dubious fixes reverted.)
Differential revision: https://reviews.llvm.org/D44188
llvm-svn: 329399
Summary:
The "previous definition is here" note is not helpful if there is no location information. The note will reference nothing in such a case. This patch first checks to see if there is location data, and if so the note diagnostic is emitted.
This fixes PR15409. The issue in the first comment seems to already be resolved. This patch addresses the second example.
Reviewers: bruno, rsmith
Reviewed By: bruno
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D44901
llvm-svn: 328712
The diagnostic system for Clang can already handle many AST nodes. Instead
of converting them to strings first, just hand the AST node directly to
the diagnostic system and let it handle the output. Minor changes in some
diagnostic output.
llvm-svn: 328688
Need to override convertConstraint to recognise amdgpu specific register names.
Differential Revision: https://reviews.llvm.org/D44533
llvm-svn: 328359
The patch adds nocf_check target independent attribute for disabling checks that were enabled by cf-protection flag.
The attribute can be appertained to functions and function pointers.
Attribute name follows GCC's similar attribute name.
Differential Revision: https://reviews.llvm.org/D41880
llvm-svn: 327768
We don't have special checks for BI_va_start in
Sema::CheckBuiltinFunctionCall, so setting the 't' flag for va_start in
Builtins.def disables semantic checking for it. That's not desired, and
IRGen crashes when it tries to generate a call to va_start that doesn't
have at least one argument.
Follow-up to r322573
Fixes PR36565
llvm-svn: 326622
The patch fixes a number of bugs related to parameter indexing in
attributes:
* Parameter indices in some attributes (argument_with_type_tag,
pointer_with_type_tag, nonnull, ownership_takes, ownership_holds,
and ownership_returns) are specified in source as one-origin
including any C++ implicit this parameter, were stored as
zero-origin excluding any this parameter, and were erroneously
printing (-ast-print) and confusingly dumping (-ast-dump) as the
stored values.
* For alloc_size, the C++ implicit this parameter was not subtracted
correctly in Sema, leading to assert failures or to silent failures
of __builtin_object_size to compute a value.
* For argument_with_type_tag, pointer_with_type_tag, and
ownership_returns, the C++ implicit this parameter was not added
back to parameter indices in some diagnostics.
This patch fixes the above bugs and aims to prevent similar bugs in
the future by introducing careful mechanisms for handling parameter
indices in attributes. ParamIdx stores a parameter index and is
designed to hide the stored encoding while providing accessors that
require each use (such as printing) to make explicit the encoding that
is needed. Attribute declarations declare parameter index arguments
as [Variadic]ParamIdxArgument, which are exposed as ParamIdx[*]. This
patch rewrites all attribute arguments that are processed by
checkFunctionOrMethodParameterIndex in SemaDeclAttr.cpp to be declared
as [Variadic]ParamIdxArgument. The only exception is xray_log_args's
argument, which is encoded as a count not an index.
Differential Revision: https://reviews.llvm.org/D43248
llvm-svn: 326602
The TypeTagForDatatype attribute had custom parsing rules that previously prevented it from being supported with square bracket notation. The ArgumentWithTypeTag attribute previously had unnecessary custom parsing that could be handled declaratively.
llvm-svn: 326052
This attribute has custom parsing rules that previously prevented it from being supported with square bracket notation. Rework the clang attribute argument parsing to be more easily extended for other custom-parsed attributes.
llvm-svn: 326036
Multiversioning SEMA failed to set the declaration as invalid on unsupported
targets. This patch does that.
Additionally, I noticed that there is no test to validate this error message.
This patch adds one, and uses 'mips' as the test architecture.
llvm-svn: 325610
There were a few issues previously with the target
attribute diagnostics implementation that lead to the
attribute being added to the AST despite having an error
in it.
This patch changes that, and adds a test to ensure it
does not get added to the AST.
Differential Revision: https://reviews.llvm.org/D43359
llvm-svn: 325364
This adds Sema and Codegen tests for the vcvtr builtins
(because they were missing).
Differential Revision: https://reviews.llvm.org/D43372
llvm-svn: 325351
Added support in clang for GCC function attribute 'artificial'. This attribute
is used to control stepping behavior of debugger with respect to inline
functions.
Patch By: Elizabeth Andrews (eandrews)
Differential Revision: https://reviews.llvm.org/D43259
llvm-svn: 325081
Summary:
This fixes a flaw in our AST: PR27098
MSVC always gives plain enums the underlying type 'int'. Clang does this
as well, but we claim the enum is "fixed", as if the user actually wrote
': int'. It means we end up emitting spurious -Wsign-compare warnings on
code like this:
enum Vals { E1, E2, E3 };
bool f(unsigned v1, Vals v2) {
return v1 == v2;
}
We think 'v2' can take on negative values because we think 'Vals' is
fixed. This fixes that.
Reviewers: rsmith
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D43110
llvm-svn: 324913
typeof expressions
This commit looks through typeof type at the original expression when diagnosing
-Wsign-compare to avoid an unfriendly diagnostic.
rdar://36588828
Differential Revision: https://reviews.llvm.org/D42561
llvm-svn: 324514
DeclContext rather than injecting it wherever we happen to be.
This avoids creating functions whose DeclContext is a struct or similar.
llvm-svn: 323998
The patch ensures that a new storage unit is created when the new bitfield's
size is wider than the available bits.
rdar://36343145
Differential Revision: https://reviews.llvm.org/D42660
llvm-svn: 323921
When a function taking transparent union is declared as taking one of
union members earlier in the translation unit, clang would hit an
"Invalid cast" assertion during EmitFunctionProlog. This case
corresponds to function f1 in test/CodeGen/transparent-union-redecl.c.
We decided to cast i32 to union because after merging function
declarations function parameter type becomes int,
CGFunctionInfo::ArgInfo type matches with ABIArgInfo type, so we decide
it is a trivial case. But these types should also be castable to
parameter declaration type which is not the case here.
Now the fix is in converting from ABIArgInfo type to VarDecl type and using
argument demotion when necessary.
Additional tests in Sema/transparent-union.c capture current behavior and make
sure there are no regressions.
rdar://problem/34949329
Reviewers: rjmccall, rafael
Reviewed By: rjmccall
Subscribers: aemerson, cfe-commits, kristof.beyls, ahatanak
Differential Revision: https://reviews.llvm.org/D41311
llvm-svn: 323156
This removes the following (already default-off) warnings from -Wextra:
-Wtautological-type-limit-compare,
-Wtautological-unsigned-zero-compare
-Wtautological-unsigned-enum-zero-compare
On the thread "[cfe-dev] -Wtautological-constant-compare issues", clang
code owners Richard Smith, John McCall, and Reid Kleckner as well as
libc++ code owner Marshall Clow stated that these new warnings are not
yet ready for prime time and shouldn't be part of -Wextra.
Furthermore, Vedant Kumar (Apple), Peter Hosek (Fuchsia), and me (Chromium)
expressed the same concerns (Vedant on that thread, Peter on
https://reviews.llvm.org/D39462, me on https://reviews.llvm.org/D41512).
So remove them from -Wextra, and remove TautologicalInRangeCompare from
TautologicalCompare too until they're usable with real-world code.
llvm-svn: 322901
Both are related to handling anonymous structures.
* clang didn't handle () around an anonymous struct variable.
* clang also crashed on syntax errors that could lead to other
syntactic constructs following the declaration of an
anonymous struct. While the code is invalid, that's not
a good reason to panic compiler.
Differential Revision: https://reviews.llvm.org/D41788
llvm-svn: 322742
GCC's attribute 'target', in addition to being an optimization hint,
also allows function multiversioning. We currently have the former
implemented, this is the latter's implementation.
This works by enabling functions with the same name/signature to coexist,
so that they can all be emitted. Multiversion state is stored in the
FunctionDecl itself, and SemaDecl manages the definitions.
Note that it ends up having to permit redefinition of functions so
that they can all be emitted. Additionally, all versions of the function
must be emitted, so this also manages that.
Note that this includes some additional rules that GCC does not, since
defining something as a MultiVersion function after a usage has been made illegal.
The only 'history rewriting' that happens is if a function is emitted before
it has been converted to a multiversion'ed function, at which point its name
needs to be changed.
Function templates and virtual functions are NOT yet supported (not supported
in GCC either).
Additionally, constructors/destructors are disallowed, but the former is
planned.
llvm-svn: 322028
Check whether we are comparing the same entity, not merely the same
declaration, and don't assume that weak declarations resolve to distinct
entities.
llvm-svn: 321976
These just overloads for _Float128. They're supported by GCC 7 and used
by glibc. APFloat support is already there so just add the overloads.
__builtin_copysignf128
__builtin_fabsf128
__builtin_huge_valf128
__builtin_inff128
__builtin_nanf128
__builtin_nansf128
This is the same support that GCC has, according to the documentation,
but limited to _Float128.
llvm-svn: 321948
This patch adds support to the attribute tablegen for specifying a [[]] attribute is allowed in C mode. This patch also adds the annotate attribute to the list of double square bracket attributes we support in C mode.
Eventually, I anticipate that this logic will be reversed (you have to opt out of allowing an attribute in C rather than opting in), but I want to see how the design plays out as more attributes are considered.
llvm-svn: 321763
Summary:
The diagnostic was mostly introduced in D38101 by me, as a reaction to wasting a lot of time, see [[ https://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20171009/206427.html | mail ]].
However, the diagnostic is pretty dumb. While it works with no false-positives,
there are some questionable cases that are diagnosed when one would argue that they should not be.
The common complaint is that it diagnoses the comparisons between an `int` and
`long` when compiling for a 32-bit target as tautological, but not when
compiling for 64-bit targets. The underlying problem is obvious: data model.
In most cases, 64-bit target is `LP64` (`int` is 32-bit, `long` and pointer are
64-bit), and the 32-bit target is `ILP32` (`int`, `long`, and pointer are 32-bit).
I.e. the common pattern is: (pseudocode)
```
#include <limits>
#include <cstdint>
int main() {
using T1 = long;
using T2 = int;
T1 r;
if (r < std::numeric_limits<T2>::min()) {}
if (r > std::numeric_limits<T2>::max()) {}
}
```
As an example, D39149 was trying to fix this diagnostic in libc++, and it was not well-received.
This *could* be "fixed", by changing the diagnostics logic to something like
`if the types of the values being compared are different, but are of the same size, then do diagnose`,
and i even attempted to do so in D39462, but as @rjmccall rightfully commented,
that implementation is incomplete to say the least.
So to stop causing trouble, and avoid contaminating upcoming release, lets do this workaround:
* move these three diags (`warn_unsigned_always_true_comparison`, `warn_unsigned_enum_always_true_comparison`, `warn_tautological_constant_compare`) into it's own `-Wtautological-constant-in-range-compare`
* Disable them by default
* Make them part of `-Wextra`
* Additionally, give `warn_tautological_constant_compare` it's own flag `-Wtautological-type-limit-compare`.
I'm not happy about that name, but i can't come up with anything better.
This way all three of them can be enabled/disabled either altogether, or one-by-one.
Reviewers: aaron.ballman, rsmith, smeenai, rjmccall, rnk, mclow.lists, dim
Reviewed By: aaron.ballman, rsmith, dim
Subscribers: thakis, compnerd, mehdi_amini, dim, hans, cfe-commits, rjmccall
Tags: #clang
Differential Revision: https://reviews.llvm.org/D41512
llvm-svn: 321691
When a function taking transparent union is declared as taking one of
union members earlier in the translation unit, clang would hit an
"Invalid cast" assertion during EmitFunctionProlog. This case
corresponds to function f1 in test/CodeGen/transparent-union-redecl.c.
We decided to cast i32 to union because after merging function
declarations function parameter type becomes int,
CGFunctionInfo::ArgInfo type matches with ABIArgInfo type, so we decide
it is a trivial case. But these types should also be castable to
parameter declaration type which is not the case here.
The fix is in checking for the trivial case if ABIArgInfo type matches with
parameter declaration type. It exposed inconsistency that we check
hasScalarEvaluationKind for different types in EmitParmDecl and
EmitFunctionProlog, and comment says they should match.
Additional tests in Sema/transparent-union.c capture current behavior and make
sure there are no regressions.
rdar://problem/34949329
Reviewers: rjmccall, rafael
Reviewed By: rjmccall
Subscribers: aemerson, cfe-commits, kristof.beyls
Differential Revision: https://reviews.llvm.org/D41311
llvm-svn: 321296
__builtin_object_size with incomplete array type in struct
The commit r316245 introduced a regression that causes an assertion failure when
Clang tries to cast an IncompleteArrayType to a PointerType when evaluating
__builtin_object_size.
rdar://36094951
Differential Revision: https://reviews.llvm.org/D41405
llvm-svn: 321222
Looking through the code, I saw a FIXME on IFunc to switch it
to a target specific attribute. In looking through it, i saw that
the no-longer-appropriately-named TargetArch didn't support ObjectFormat
checking.
This patch changes the name of TargetArch to TargetSpecific
(since it checks much more than just Arch), makes "Arch" optional, adds
support for ObjectFormat, better documents the TargetSpecific type, and
changes IFunc over to a TargetSpecificAttr.
Differential Revision: https://reviews.llvm.org/D41303
llvm-svn: 321201
This mimics FileCheck's --check-prefixes option.
The default prefix is "expected". That is, "-verify" is equivalent to
"-verify=expected".
The goal is to permit exercising a single test suite source file with different
compiler options producing different sets of diagnostics. While cpp can be
combined with the existing -verify to accomplish the same goal, source is often
easier to maintain when it's not cluttered with preprocessor directives or
duplicate passages of code. For example, this patch also rewrites some existing
clang tests to demonstrate the benefit of this feature.
Patch by Joel E. Denny, thanks!
Differential Revision: https://reviews.llvm.org/D39694
llvm-svn: 320908
There are many more expr types that can be a capability expr, like
CXXThisExpr, CallExpr, MemberExpr. Instead of enumerating all of them,
just check typeHasCapability for any type given.
Also add & and * operators to allowed unary operators.
Differential Revision: https://reviews.llvm.org/D41224
llvm-svn: 320753
and fold together into a single function.
In so doing, fix a handful of remaining bugs where we would report false
positives or false negatives if we promote a signed value to an unsigned type
for the comparison.
This re-commits r320122 and r320124, minus two changes:
* Comparisons between a constant and a non-constant expression of enumeration
type never warn, not even if the constant is out of range. We should be
warning about the creation of such a constant, not about its use.
* We do not use more precise bit-widths for comparisons against bit-fields.
The more precise diagnostics probably are the right thing, but we should
consider moving them under their own warning flag.
Other than the refactoring, this patch should only change the behavior for the
buggy cases (where the warnings didn't take into account that promotion from
signed to unsigned can leave a range of inaccessible values in the middle of
the promoted type).
llvm-svn: 320211
> Unify implementation of our two different flavours of -Wtautological-compare.
>
> In so doing, fix a handful of remaining bugs where we would report false
> positives or false negatives if we promote a signed value to an unsigned type
> for the comparison.
This caused a new warning in Chromium:
../../base/trace_event/trace_log.cc:1545:29: error: comparison of constant 64
with expression of type 'unsigned int' is always true
[-Werror,-Wtautological-constant-out-of-range-compare]
DCHECK(handle.event_index < TraceBufferChunk::kTraceBufferChunkSize);
~~~~~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The 'unsigned int' is really a 6-bit bitfield, which is why it's always
less than 64.
I thought we didn't use to warn (with out-of-range-compare) when comparing
against the boundaries of a type?
llvm-svn: 320162
In so doing, fix a handful of remaining bugs where we would report false
positives or false negatives if we promote a signed value to an unsigned type
for the comparison.
llvm-svn: 320122
This is a follow up of r302131, in which we forgot to add SemaChecking
tests. Adding these tests revealed two problems which have been fixed:
- added missing intrinsic __qdbl,
- properly range checking ssat16 and usat16.
Differential Revision: https://reviews.llvm.org/D40888
llvm-svn: 320019
An enumeration with a fixed underlying type can have any value in its
underlying type, not just those spanned by the values of its enumerators.
llvm-svn: 319875
Fedora27 is using a new version of glibc that refers to the _Float128 type. This
patch adds that name as an alias to float128. I also added some predefined macro
values for the digits, mantissa, epilon, etc (FloatMacros). For the test case, I
copied an existing float128 test. This functionality needs work long term, but
it should be sufficient to tread water for a while. At Intel we have test
servers running our LLVM compiler with various open source workloads, the server
has been upgraded to Fedora27 so many workloads are failing due to _Float128.
Patch-By: mibintc
Differential Revision: https://reviews.llvm.org/D40673
llvm-svn: 319703
This also clarifies some terminology used by the diagnostic (methods -> Objective-C methods, fields -> non-static data members, etc).
Many of the tests needed to be updated in multiple places for the diagnostic wording tweaks. The first instance of the diagnostic for that attribute is fully specified and subsequent instances cut off the complete list (to make it easier if additional subjects are added in the future for the attribute).
llvm-svn: 319002
Basically a regression after r316268.
However the diagnostic is correct, but the test coverage is bad.
So just like rL316500, introduce yet more tests,
and adjust the release notes.
See https://bugs.llvm.org/show_bug.cgi?id=35200
llvm-svn: 317421
rL316268 / D39122 has fixed PR35009, and now when in C,
these three(?) diagnostics properly use the enum's underlying
datatype.
While it was fixed, the test coverage was clearly insufficient,
because the -Wsign-compare change didn't show up in any of the
tests, until it was reported in the post-commit mail for rL316268.
So add the test for the -Wsign-compare diagnostic for enum
for C code, and while there, document this in the release notes.
The fix itself was obviously correct, so unless we want to silence
this new diagnosed case, i deem this commit to be NFC.
llvm-svn: 316500
Allow Obj-C ivars with incomplete array type but only as the last ivar.
Also add a requirement for ivars that contain a flexible array member to
be at the end of class too. It is possible to add in a subclass another
ivar at the end but we'll emit a warning in this case. Also we'll emit a
warning if a variable sized ivar is declared in class extension or in
implementation because subclasses won't know they should avoid adding
new ivars.
In ARC incomplete array objects are treated as __unsafe_unretained so
require them to be marked as such.
Prohibit synthesizing ivars with flexible array members because order of
synthesized ivars is not obvious and tricky to control. Spelling out
ivar explicitly gives control to developers and helps to avoid surprises
with unexpected ivar ordering.
For C and C++ changed diagnostic to tell explicitly a field is not the
last one and point to the next field. It is not as useful as in Obj-C
but it is an improvement and it is consistent with Obj-C. For C for
unions emit more specific err_flexible_array_union instead of generic
err_field_incomplete.
rdar://problem/21054495
Reviewers: rjmccall, theraven
Reviewed By: rjmccall
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D38773
llvm-svn: 316381
Summary:
As Mattias Eriksson has reported in PR35009, in C, for enums, the underlying type should
be used when checking for the tautological comparison, unlike C++, where the enumerator
values define the value range. So if not in CPlusPlus mode, use the enum underlying type.
Also, i have discovered a problem (a crash) when evaluating tautological-ness of the following comparison:
```
enum A { A_a = 0 };
if (a < 0) // expected-warning {{comparison of unsigned enum expression < 0 is always false}}
return 0;
```
This affects both the C and C++, but after the first fix, only C++ code was affected.
That was also fixed, while preserving (i think?) the proper diagnostic output.
And while there, attempt to enhance the test coverage.
Yes, some tests got moved around, sorry about that :)
Fixes PR35009
Reviewers: aaron.ballman, rsmith, rjmccall
Reviewed By: aaron.ballman
Subscribers: Rakete1111, efriedma, materi, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D39122
llvm-svn: 316268
Changes behavior introduced in r298369 to only error out on
vector component invalid length access on OpenCL mode.
Differential Revision: https://reviews.llvm.org/D38868
rdar://problem/33568748
llvm-svn: 316016
The first attempt, rL315614 was reverted because one libcxx
test broke, and i did not know at the time how to deal with it.
Summary:
Currently, clang only diagnoses completely out-of-range comparisons (e.g. `char` and constant `300`),
and comparisons of unsigned and `0`. But gcc also does diagnose the comparisons with the
`std::numeric_limits<>::max()` / `std::numeric_limits<>::min()` so to speak
Finally Fixes https://bugs.llvm.org/show_bug.cgi?id=34147
Continuation of https://reviews.llvm.org/D37565
Reviewers: rjmccall, rsmith, aaron.ballman
Reviewed By: rsmith
Subscribers: rtrieu, jroelofs, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D38101
llvm-svn: 315875
Summary:
Currently, clang only diagnoses completely out-of-range comparisons (e.g. `char` and constant `300`),
and comparisons of unsigned and `0`. But gcc also does diagnose the comparisons with the
`std::numeric_limits<>::max()` / `std::numeric_limits<>::min()` so to speak
Finally Fixes https://bugs.llvm.org/show_bug.cgi?id=34147
Continuation of https://reviews.llvm.org/D37565
Reviewers: rjmccall, rsmith, aaron.ballman
Reviewed By: rsmith
Subscribers: rtrieu, jroelofs, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D38101
llvm-svn: 315614
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
As reported on cfe-commits, r314262 resulted in tentatively-defined
variables not being excluded for the warning.
Patch By: Elizabeth Andrews
llvm-svn: 314939
We were injecting the function into the wrong semantic context, resulting in it
failing to be registered as a global for redeclaration lookup. As a
consequence, we accepted invalid code since r310616.
Fixing that resulted in the "out-of-scope declaration" diagnostic firing a lot
more often. It turned out that warning codepath was non-conforming, because it
did not cause us to inject the implicitly-declared function into the enclosing
block scope. We now only warn if the type of the out-of-scope declaration
doesn't match the type of an implicitly-declared function; in all other cases,
we produce the normal warning for an implicitly-declared function.
llvm-svn: 314871
In C++, such initialization of std::array<T, N> types is guaranteed to work by
the standard, is completely idiomatic, and the "suggested" alternative from
Clang was technically invalid.
llvm-svn: 314838
C11 standard refers to the unsigned counterpart of the type ptrdiff_t
in the paragraph 7.21.6.1p7 where it defines the format specifier %tu.
In Clang (in PrintfFormatString.cpp, lines 508-510) there is a FIXME for this case,
in particular, Clang didn't diagnose %tu issues at all, i.e.
it didn't emit any warnings on the code printf("%tu", 3.14).
In this diff we add a method getUnsignedPointerDiffType for getting the corresponding type
similarly to how it's already done in the other analogous cases (size_t, ssize_t, ptrdiff_t etc)
and fix -Wformat diagnostics for %tu plus the emitted fix-it as well.
Test plan: make check-all
Differential revision: https://reviews.llvm.org/D38270
llvm-svn: 314470
Currently AMDGPU inline asm only allow v and s as register names in constraints.
This patch allows the following register names in constraints: (n, m is unsigned integer, n < m)
v
s
{vn} or {v[n]}
{sn} or {s[n]}
{S} , where S is a special register name
{v[n:m]}
{s[n:m]}
Differential Revision: https://reviews.llvm.org/D37568
llvm-svn: 314452
Currently, if _attribute_((section())) is used for extern variables,
section information is not emitted in generated IR when the variables are used.
This is expected since sections are not generated for external linkage objects.
However NiosII requires this information as it uses special GP-relative accesses
for any objects that use attribute section (.sdata). GCC keeps this attribute in
middle-end.
This change emits the section information for all targets.
Patch By: Elizabeth Andrews
Differential Revision:https://reviews.llvm.org/D36487
llvm-svn: 314262
This commit fixes a bug in the handling of storage-only __fp16 vectors
where clang didn't promote __fp16 vector operands to float vectors.
Conceptually, it performs the following transformation on the AST in
CreateBuiltinBinOp and CreateBuiltinUnaryOp:
(Before)
typedef __fp16 half4 __attribute__ ((vector_size (8)));
typedef float float4 __attribute__ ((vector_size (16)));
half4 hv0, hv1, hv2, hv3;
hv0 = hv1 + hv2 + hv3;
(After)
float4 t0 = (float4)hv1 + (float4)hv2;
float4 t1 = t0 + (float4)hv3;
hv0 = (half4)t1;
Note that this commit fixes the bug for targets that set
HalfArgsAndReturns to true (ARM and ARM64). Targets using intrinsics
such as llvm.convert.to.fp16 to handle __fp16 are still broken.
rdar://problem/20625184
Differential Revision: https://reviews.llvm.org/D32520
llvm-svn: 314056
Fix for too aggressive error err_type_defined_in_enum introduced in
r313386. Defining tags inside enumerations is prohibited in C++ but
allowed in C.
Reviewers: aaron.ballman, rnk, doug.gregor
Reviewed By: rnk
Subscribers: alberto_magni, cfe-commits
Differential Revision: https://reviews.llvm.org/D38109
llvm-svn: 313894
As Aaron Ballman has pointed out, that is not really correct.
So the key problem there is the invalidity of the testcase.
Revert r313747, and rework testcase in such a way, so these
details (platform-specific default enum sigdness) are
accounted for.
Also, add a C++-specific testcase.
llvm-svn: 313756
Recommit. Original commit was reverted because buildbots broke.
The error was only reproducible in the build with assertions.
The problem was that the diagnostic expected true/false as
bool, while it was provided as string "true"/"false".
Summary:
As requested by Sam McCall:
> Enums (not new I guess). Typical case: if (enum < 0 || enum > MAX)
> The warning strongly suggests that the enum < 0 check has no effect
> (for enums with nonnegative ranges).
> Clang doesn't seem to optimize such checks out though, and they seem
> likely to catch bugs in some cases. Yes, only if there's UB elsewhere,
> but I assume not optimizing out these checks indicates a deliberate
> decision to stay somewhat compatible with a technically-incorrect
> mental model.
> If this is the case, should we move these to a
> -Wtautological-compare-enum subcategory?
Reviewers: rjmccall, rsmith, aaron.ballman, sammccall, bkramer, djasper
Reviewed By: aaron.ballman
Subscribers: jroelofs, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D37629
llvm-svn: 313745
This reverts commit r313722.
It looks like compiler-rt/lib/tsan/rtl/tsan_libdispatch_mac.cc cannot be
compiled because some of the functions declared in the file do not match
the ones in the SDK headers (which are annotated with 'noescape').
llvm-svn: 313725
The attribute informs the compiler that the annotated pointer parameter
of a function cannot escape and enables IRGen to attach attribute
'nocapture' to parameters that are annotated with the attribute. That is
the only optimization that currently takes advantage of 'noescape', but
there are other optimizations that will be added later that improves
IRGen for ObjC blocks.
rdar://problem/19886775
Differential Revision: https://reviews.llvm.org/D32210
llvm-svn: 313722
The attribute informs the compiler that the annotated pointer parameter
of a function cannot escape and enables IRGen to attach attribute
'nocapture' to parameters that are annotated with the attribute. That is
the only optimization that currently takes advantage of 'noescape', but
there are other optimizations that will be added later that improves
IRGen for ObjC blocks.
rdar://problem/19886775
Differential Revision: https://reviews.llvm.org/D32520
llvm-svn: 313720
The recently behavior in the code that these tests were meant to be checking will be ammended as soon as a suitable change can be properly reviewed.
llvm-svn: 313684
Summary:
As requested by Sam McCall:
> Enums (not new I guess). Typical case: if (enum < 0 || enum > MAX)
> The warning strongly suggests that the enum < 0 check has no effect
> (for enums with nonnegative ranges).
> Clang doesn't seem to optimize such checks out though, and they seem
> likely to catch bugs in some cases. Yes, only if there's UB elsewhere,
> but I assume not optimizing out these checks indicates a deliberate
> decision to stay somewhat compatible with a technically-incorrect
> mental model.
> If this is the case, should we move these to a
> -Wtautological-compare-enum subcategory?
Reviewers: rjmccall, rsmith, aaron.ballman, sammccall, bkramer, djasper
Reviewed By: aaron.ballman
Subscribers: jroelofs, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D37629
llvm-svn: 313677