FPContractModeKind is the codegen option flag which is already ternary (off,
on, fast). This makes it universally the type for the contractable info
across the front-end:
* In FPOptions (i.e. in the Sema + in the expression nodes).
* In LangOpts::DefaultFPContractMode which is the option that initializes
FPOptions in the Sema.
Another way to look at this change is that before fp-contractable on/off were
the only states handled to the front-end:
* For "on", FMA folding was performed by the front-end
* For "fast", we simply forwarded the flag to TargetOptions to handle it in
LLVM
Now off/on/fast are all exposed because for fast we will generate
fast-math-flags during CodeGen.
This is toward moving fp-contraction=fast from an LLVM TargetOption to a
FastMathFlag in order to fix PR25721.
---
This is a recommit of r299027 with an adjustment to the test
CodeGenCUDA/fp-contract.cu. The test assumed that even
though -ffp-contract=on is passed FE-based folding of FMA won't happen.
This is obviously wrong since the user is asking for this explicitly with the
option. CUDA is different that -ffp-contract=fast is on by default.
The test used to "work" because contract=fast and contract=on were maintained
separately and we didn't fold in the FE because contract=fast was on due to
the target-default. This patch consolidates the contract=on/fast/off state
into a ternary state hence the change in behavior.
---
Differential Revision: https://reviews.llvm.org/D31167
llvm-svn: 299033
FPContractModeKind is the codegen option flag which is already ternary (off,
on, fast). This makes it universally the type for the contractable info
across the front-end:
* In FPOptions (i.e. in the Sema + in the expression nodes).
* In LangOpts::DefaultFPContractMode which is the option that initializes
FPOptions in the Sema.
Another way to look at this change is that before fp-contractable on/off were
the only states handled to the front-end:
* For "on", FMA folding was performed by the front-end
* For "fast", we simply forwarded the flag to TargetOptions to handle it in
LLVM
Now off/on/fast are all exposed because for fast we will generate
fast-math-flags during CodeGen.
This is toward moving fp-contraction=fast from an LLVM TargetOption to a
FastMathFlag in order to fix PR25721.
Differential Revision: https://reviews.llvm.org/D31167
llvm-svn: 299027
Summary: After examining the remaining uses of LangOptions.ObjCAutoRefCount, found a some additional places to also check for ObjCWeak not covered by previous test cases. Added a test file to verify all the code paths that were changed.
Reviewers: rsmith, doug.gregor, rjmccall
Reviewed By: rjmccall
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D31007
llvm-svn: 299015
Summary: clang should produce the same errors Objective-C classes that cannot be assigned to weak pointers under both -fobjc-arc and -fobjc-weak. Check for ObjCWeak along with ObjCAutoRefCount when analyzing pointer conversions. Add an -fobjc-weak pass to the existing arc-unavailable-for-weakref test cases to verify the behavior is the same.
Reviewers: rsmith, doug.gregor, rjmccall
Reviewed By: rjmccall
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D31006
llvm-svn: 299014
Summary: -Warc-repeated-use-of-weak should produce the same warnings with -fobjc-weak as it does with -objc-arc. Also check for ObjCWeak along with ObjCAutoRefCount when recording the use of an evaluated weak variable. Add a -fobjc-weak run to the existing arc-repeated-weak test case and adapt it slightly to work in both modes.
Reviewers: rsmith, doug.gregor, jordan_rose, rjmccall
Reviewed By: rjmccall
Subscribers: arphaman, rjmccall, cfe-commits
Differential Revision: https://reviews.llvm.org/D31005
llvm-svn: 299011
Summary: Similar to ARC, in ObjCWeak Objective-C object pointers qualified with a weak lifetime are not POD or trivial types. Update the type trait code to reflect this. Copy and adapt the arc-type-traits.mm test case to verify correctness.
Reviewers: rsmith, doug.gregor, rjmccall
Reviewed By: rjmccall
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D31004
llvm-svn: 299010
Summary: When adding an Objective-C retainable type member to a C++ class, also check the LangOpts.ObjCWeak flag and the lifetime qualifier so __weak qualified Objective-C pointer members cause the class to be a non-POD type with non-trivial special members, so the compiler always emits the necessary runtime calls for copying, moving, and destroying the weak member. Otherwise, Objective-C++ classes with weak Objective-C pointer members compiled with -fobjc-weak exhibit undefined behavior if the C++ class is classified as a POD type.
Reviewers: rsmith, benlangmuir, doug.gregor, rjmccall
Reviewed By: rjmccall
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D31003
llvm-svn: 299008
If there is an unresolved member access AST node, and the base is
implicit, do not access/use it for generating candidate overloads for
code completion results.
Fixes PR31093.
llvm-svn: 298903
FIXME: ActOnReturnStmt expects a scope that is inside of the function, due
to CheckJumpOutOfSEHFinally(*this, ReturnLoc, *CurScope->getFnParent());
S.getCurScope()->getFnParent() == nullptr at ActOnFinishFunctionBody when
CoroutineBodyStmt is built. Figure it out and fix it.
llvm-svn: 298893
Summary:
If promise_type has get_return_object_on_allocation_failure defined,
check if an allocation function returns nullptr, and if so,
return the result of get_return_object_on_allocation_failure().
Reviewers: rsmith, EricWF
Reviewed By: EricWF
Subscribers: mehdi_amini, cfe-commits
Differential Revision: https://reviews.llvm.org/D31399
llvm-svn: 298891
Summary:
This patch implements parsing of [[clang::suppress(rule, ...)]]
and [[gsl::suppress(rule, ...)]] attributes.
C++ Core Guidelines depend heavily on tool support for
rule enforcement. They also propose a way to suppress
warnings [1] which is by annotating any ancestor in AST
with the C++11 attribute [[gsl::suppress(rule1,...)]].
To have a mechanism to suppress non-C++ Core
Guidelines specific, an additional spelling of [[clang::suppress]]
is defined.
For example, to suppress the warning cppcoreguidelines-slicing,
one could do
```
[[clang::suppress("cppcoreguidelines-slicing")]]
void f() { ... code that does slicing ... }
```
or
```
void g() {
Derived b;
[[clang::suppress("cppcoreguidelines-slicing")]]
Base a{b};
[[clang::suppress("cppcoreguidelines-slicing")]] {
doSomething();
Base a2{b};
}
}
```
This parsing can then be used by clang-tidy, which includes multiple
C++ Core Guidelines rules, to suppress warnings (see
https://reviews.llvm.org/D24888).
For the exact naming of the rule in the attribute, there
are different possibilities, which will be defined in the
corresponding clang-tidy patch.
Currently, clang-tidy supports suppressing of warnings through "//
NOLINT" comments. There are some advantages that the attribute has:
- Suppressing specific warnings instead of all warnings
- Suppressing warnings in a block (namespace, function, compound
statement)
- Code formatting may split a statement into multiple lines,
thus a "// NOLINT" comment may be on the wrong line
I'm looking forward to your comments!
[1] https://github.com/isocpp/CppCoreGuidelines/blob/master/CppCoreGuidelines.md#inforce-enforcement
Reviewers: alexfh, aaron.ballman, rsmith
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D24886
llvm-svn: 298880
Sema holds the current FPOptions which is adjusted by 'pragma STDC
FP_CONTRACT'. This then gets propagated into expression nodes as they are
built.
This encapsulates FPOptions so that this propagation happens opaquely rather
than directly with the fp_contractable on/off bit. This allows controlled
transitioning of fp_contractable to a ternary value (off, on, fast). It will
also allow adding more fast-math flags later.
This is toward moving fp-contraction=fast from an LLVM TargetOption to a
FastMathFlag in order to fix PR25721.
Differential Revision: https://reviews.llvm.org/D31166
llvm-svn: 298877
for unused values.
This fixes a regression caused by r298676, where constructor calls to
classes with non-trivial dtor were marked as unused if the first
argument is an initializer list. This is inconsistent (as the test
shows) and also warns on a reasonbly common code pattern where people
just call constructors to create and immediately destroy an object.
llvm-svn: 298853
This change fixes a crash on initialization of a reference from ({}) during
template instantiation and incidentally improves diagnostics.
This reverts a prior attempt to handle this in r286721. Instead, we teach the
initialization code that initialization cannot be performed if a source type
is required and the initializer is an initializer list (which is not an
expression and does not have a type), and likewise for function-style cast
expressions.
llvm-svn: 298676
Correct class-template deprecation behavior
Based on the comment in the test, and my reading of the standard, a deprecated warning should be issued in the following case:
template<typename T> [[deprecated]] class Foo{}; Foo<int> f;
This was not the case, because the ClassTemplateSpecializationDecl creation did not also copy the deprecated attribute.
Note: I did NOT audit the complete set of attributes to see WHICH ones should be copied, so instead I simply copy ONLY the deprecated attribute.
Previous DiffRev: https://reviews.llvm.org/D27486, was reverted.
This patch fixes the issues brought up here by the reverter: https://reviews.llvm.org/rL298410
Differential Revision: https://reviews.llvm.org/D31245
llvm-svn: 298634
that became supported after r297019
The commit r297019 expanded the performSelector ObjC method family heuristic
to ensure that -Wobjc-unsafe-perform-selector covers all performSelector
variations. However, this made the -Warc-performSelector-leaks too noisy, as
that warning produces mostly false positives since the selector is unknown.
This commit reverts the ObjC method family heuristics introduced in r297019.
This ensures that -Warc-performSelector-leaks isn't too noisy. The commit still
preserves the coverage of -Wobjc-unsafe-perform-selector.
rdar://31124629
llvm-svn: 298587
Summary:
This patch adopts the recent changes that renamed `set_exception(exception_pointer)` to `unhandled_exception()`.
Additionally `unhandled_exception()` is now required, and so an error is emitted when exceptions are enabled but the promise type does not provide the member.
When exceptions are disabled a warning is emitted instead of an error, The warning notes that the `unhandled_exception()` function is required when exceptions are enabled.
Reviewers: rsmith, GorNishanov, aaron.ballman, majnemer
Reviewed By: GorNishanov
Subscribers: mehdi_amini, cfe-commits
Differential Revision: https://reviews.llvm.org/D30859
llvm-svn: 298565
We don't know whether some other instantiation of the template might be able to
reach the annotation, so warning on it has a high chance of false positives.
Patch by Ahmed Asadi!
Differential Revision: https://reviews.llvm.org/D31069
llvm-svn: 298477
Based on the comment in the test, and my reading of the standard, a deprecated warning should be issued in the following case:
template<typename T> [[deprecated]] class Foo{}; Foo<int> f;
This was not the case, because the ClassTemplateSpecializationDecl creation did not also copy the deprecated attribute.
Note: I did NOT audit the complete set of attributes to see WHICH ones should be copied, so instead I simply copy ONLY the deprecated attribute.
Differential Revision: https://reviews.llvm.org/D27486
llvm-svn: 298410
Summary: I added a new rank to ImplicitConversionRank enum to resolve the function overload ambiguity with vector types. Rank of scalar types conversion is lower than vector splat. So, we can choose which function should we call. See test for more details.
Reviewers: Anastasia, cfe-commits
Reviewed By: Anastasia
Subscribers: bader, yaxunl
Differential Revision: https://reviews.llvm.org/D30816
llvm-svn: 298366
This commit adds support for a new attribute that will be used to
distinguish between extensible and inextensible enums. There are three
main purposes of this attribute:
1. Give better control over when enum-related warnings are issued.
For example, in the code below, clang will not issue a -Wassign-enum
warning if the enum is marked "open":
enum __attribute__((enum_extensibility(closed))) EnumClosed {
B0 = 1, B1 = 10
};
enum __attribute__((enum_extensibility(open))) EnumOpen {
C0 = 1, C1 = 10
};
enum EnumClosed ec = 100; // warning issued
enum EnumOpen eo = 100; // no warning
2. Enable code-completion and debugging tools to offer better
suggestions.
3. Make it easier for swift's clang importer to determine which swift
type an enum should be mapped to.
For more details, see the discussion I started on cfe-dev:
http://lists.llvm.org/pipermail/cfe-dev/2017-February/052748.html
rdar://problem/12764379
rdar://problem/23145650
Differential Revision: https://reviews.llvm.org/D30766
llvm-svn: 298332
Summary:
3.4.6 [basic.lookup.udir] paragraph 1:
In a using-directive or namespace-alias-definition, during the lookup for a namespace-name or for a name in a nested-name-specifier, only namespace names are considered.
Reviewers: rsmith, aaron.ballman
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D30848
llvm-svn: 298126
This enhances the AST to keep track of locations of the names in those ObjC property attributes, and reports them for indexing.
Patch by Nathan Hawes!
https://reviews.llvm.org/D30907
llvm-svn: 297972
The instance method 'self' does not actually return an over-retained object,
so we shouldn't report an error when it's used with 'performSelector'.
rdar://31071620
llvm-svn: 297961
instance of a qualified Class object when that instance method comes from
a protocol that's implemented by NSObject
Instance methods from a root class like NSObject are also class methods because
the metaclass of root class derives from that root class. Therefore, we can
avoid the warning for instances of qualified Class objects that point to classes
that derive from NSObject. Note that we actually don't know if a Class instance
points to a class that derives from NSObject at compile-time, so we have to
make a reasonable assumption that the majority of instances will do so.
rdar://22812517
llvm-svn: 297862
This adds -Wbitfield-enum-conversion, which warns on implicit
conversions that happen on bitfield assignment that change the value of
some enumerators.
Values of enum type typically take on a very small range of values, so
they are frequently stored in bitfields. Unfortunately, there is no
convenient way to calculate the minimum number of bits necessary to
store all possible values at compile time, so users usually hard code a
bitwidth that works today and widen it as necessary to pass basic
testing and validation. This is very error-prone, and leads to stale
widths as enums grow. This warning aims to catch such bugs.
This would have found two real bugs in clang and two instances of
questionable code. See r297680 and r297654 for the full description of
the issues.
This warning is currently disabled by default while we investigate its
usefulness outside of LLVM.
The major cause of false positives with this warning is this kind of
enum:
enum E { W, X, Y, Z, SENTINEL_LAST };
The last enumerator is an invalid value used to validate inputs or size
an array. Depending on the prevalance of this style of enum across a
codebase, this warning may be more or less feasible to deploy. It also
has trouble on sentinel values such as ~0U.
Reviewers: rsmith, rtrieu, thakis
Reviewed By: thakis
Subscribers: hfinkel, voskresensky.vladimir, sashab, cfe-commits
Differential Revision: https://reviews.llvm.org/D30923
llvm-svn: 297761
The only valid values for scale immediate of scatter/gather builtins are 1, 2, 4, or 8. This patch enforces this in the frontend otherwise we generate invalid instruction encodings in the backend.
Differential Revision: https://reviews.llvm.org/D30875
llvm-svn: 297642
Given that we have already explicitly stated in the qualifier that the
expression is __unaligned, it makes little sense to diagnose that the address
of the packed member may not be aligned.
Differential Revision: https://reviews.llvm.org/D30884
llvm-svn: 297620
Summary:
Some coroutine diagnostics need to point to the location of the first coroutine keyword in the function, like when diagnosing a `return` inside a coroutine. Previously we did this by storing each *valid* coroutine statement in a list and select the first one to use in diagnostics. However if every coroutine statement is invalid we would have no location to point to.
This patch fixes the storage of the first coroutine statement location, ensuring that it gets stored even when the resulting AST node would be invalid.
This patch also removes the `CoroutineStmts` list in `FunctionScopeInfo` because it was unused.
Reviewers: rsmith, GorNishanov, aaron.ballman
Reviewed By: GorNishanov
Subscribers: mehdi_amini, cfe-commits
Differential Revision: https://reviews.llvm.org/D30776
llvm-svn: 297547
Summary:
Create only one OpaqueValue for await_ready/await_suspend/await_resume.
Store OpaqueValue used in the CoroutineSuspendExpr node, so that CodeGen does not have to hunt looking for it.
Reviewers: rsmith, EricWF, aaron.ballman
Reviewed By: EricWF
Subscribers: mehdi_amini, cfe-commits
Differential Revision: https://reviews.llvm.org/D30775
llvm-svn: 297541
Removes immediate range checks for these instructions, since they have GPR
rt as their input operand.
Patch by Stefan Maksimovic.
Differential Revision: https://reviews.llvm.org/D30693
llvm-svn: 297485
1. Reimplemented conditional operator so that it checks
compatibility of unqualified pointees of the 2nd and
the 3rd operands (C99, OpenCL v2.0 6.5.15).
Define QualTypes compatibility for OpenCL as following:
- corresponding types are compatible (C99 6.7.3)
- CVR-qualifiers are equal (C99 6.7.3)
- address spaces are equal (implementation defined)
2. Added generic address space to Itanium mangling.
Review: D30037
Patch by Dmitry Borisenkov!
llvm-svn: 297468
Summary:
This patch adds passing a coroutine_handle object to await_suspend calls.
It builds the coroutine_handle using coroutine_handle<PromiseType>::from_address(__builtin_coro_frame()).
(a revision of https://reviews.llvm.org/D26316 that for some reason refuses to apply via arc patch)
Reviewers: GorNishanov
Subscribers: mehdi_amini, cfe-commits, EricWF
Differential Revision: https://reviews.llvm.org/D30769
llvm-svn: 297356
Summary:
The changes contained in this patch are:
1. Defines a new AST node `CoawaitDependentExpr` for representing co_await expressions while the promise type is still dependent.
2. Correctly detect and transform the 'co_await' operand to `p.await_transform(<expr>)` when possible.
3. Change the initial/final suspend points to build during the initial parse, so they have the correct operator co_await lookup results.
4. Fix transformation of the CoroutineBodyStmt so that it doesn't re-build the final/initial suspends.
@rsmith: This change is a little big, but it's not trivial for me to split it up. Please let me know if you would prefer this submitted as multiple patches.
Reviewers: rsmith, GorNishanov
Reviewed By: rsmith
Subscribers: ABataev, rsmith, mehdi_amini, cfe-commits
Differential Revision: https://reviews.llvm.org/D26057
llvm-svn: 297093
Previously when a coroutine was building the implicit setup/destroy
constructs it would emit diagostics about failures on the first co_await/co_return/co_yield
it encountered. This was confusing because that construct may not itself be ill-formed.
This patch moves the diagnostics to the function start instead.
llvm-svn: 297089
that return record or vector types
The performSelector family of methods from Foundation use objc_msgSend to
dispatch the selector invocations to objects. However, method calls to methods
that return record types might have to use the objc_msgSend_stret as the return
value won't find into the register. This is also supported by this sentence from
performSelector documentation: "The method should not have a significant return
value and should take a single argument of type id, or no arguments". This
commit adds a new warning that warns when a selector which corresponds to a
method that returns a record type is passed into performSelector.
rdar://12056271
Differential Revision: https://reviews.llvm.org/D30174
llvm-svn: 297019
Summary:
Functions with the "xray_log_args" attribute will tell LLVM to emit a special
XRay sled for compiler-rt to copy any call arguments to your logging handler.
Reviewers: dberris
Reviewed By: dberris
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D29704
llvm-svn: 296999
and the nature of a declaration
This commit adds an external_source_symbol attribute to Clang. This attribute
specifies that a declaration originates from an external source and describes
the nature of that source. This attribute will be used to improve IDE features
like 'jump-to-definition' for mixed-language projects or project that use
auto-generated code.
rdar://30423368
Differential Revision: https://reviews.llvm.org/D29819
llvm-svn: 296649
Summary:
Don't warn about unused lambda captures that involve copying a
value of a type that cannot be trivially copied and destroyed.
Fixes PR31977
Reviewers: rsmith, aaron.ballman
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D30327
llvm-svn: 296602
potential capture list.
Fix Sema::getCurLambda() to return the innermost lambda scope when there
is a block enclosed in the lambda. Previously, the method would return a
nullptr in such cases, which would prevent a variable captured by the
enclosed block to be added to the lambda scope's potential capture list.
rdar://problem/28412462
Differential Revision: https://reviews.llvm.org/D25556
llvm-svn: 296584
The exisiting warning for inconsistent overrides does not include the destructor
as it was noted in review that it was too noisy. Instead, add to a separate
warning group that is off by default for users who want consistent warnings
between methods and destructors.
llvm-svn: 296572
Essentially, as a base class constructor does not construct virtual bases, such
a constructor for an abstract class does not need the corresponding base class
construction to be valid, and likewise for destructors.
This creates an awkward situation: clang will sometimes generate references to
the complete object and deleting destructors for an abstract class (it puts
them in the construction vtable for a derived class). But we can't generate a
"correct" version of these because we can't generate references to base class
constructors any more (if they're template specializations, say, we might not
have instantiated them and can't assume any other TU will emit a copy).
Fortunately, we don't need to, since no correct program can ever invoke them,
so instead emit symbols that just trap.
We should stop emitting references to these symbols, but still need to emit
definitions for compatibility.
llvm-svn: 296275
The goal of this is to fix a bug in modules where we'd merge
FunctionDecls that differed in their pass_object_size attributes. Since
we can overload on the presence of pass_object_size attributes, this
behavior is incorrect.
We don't represent `N` in `pass_object_size(N)` as part of
ExtParameterInfo, since it's an error to overload solely on the value of
N. This means that we have a bug if we have two modules that declare
functions that differ only in their pass_object_size attrs, like so:
// In module A, from a.h
void foo(char *__attribute__((pass_object_size(0))));
// In module B, from b.h
void foo(char *__attribute__((pass_object_size(1))));
// In module C, in main.c
#include "a.h"
#include "b.h"
At the moment, we'll merge the foo decls, when we should instead emit a
diagnostic about an invalid overload. We seem to have similar (silent)
behavior if we overload only on the return type of `foo` instead; I'll
try to find a good place to put a FIXME (or I'll just file a bug) soon.
This patch also fixes a bug where we'd not output the proper extended
parameter info for declarations with pass_object_size attrs.
llvm-svn: 296076
Rather than attempting to compare whether the previous and current top of
context stack are "equal" (which fails for a number of reasons, such as the
context stack entries containing pointers to objects on the stack, or reaching
the same "top of stack" entry through two different paths), track the depth of
context stack at which we last emitted a note and invalidate it when we pop the
context stack to less than that depth.
This causes us to emit some missing "in instantiation of" notes and to stop
emitting redundant "in instantiation of" stacks matching the previous stack in
rare cases.
llvm-svn: 295921
A 'decltype(auto)' parameter can match any other kind of non-type template
parameter, so should be usable in place of any other parameter in a template
template argument. The standard is sadly extremely unclear on how this is
supposed to work, but this seems like the obviously-correct result.
It's less clear whether an 'auto' parameter should be able to match
'decltype(auto)', since the former cannot be used if the latter turns out to be
used for a reference type, but if we disallow that then consistency suggests we
should also disallow 'auto' matching 'T' for the same reason, defeating
intended use cases of the feature.
llvm-svn: 295866
checkNestingOfRegions uses CancelRegion to determine whether cancel and
cancellation point are valid in the given nesting. This leads to unuseful
diagnostics if CancelRegion is invalid. The given test case has produced:
region cannot be closely nested inside 'parallel' region
As a solution, introduce checkCancelRegion and call it first to get the
expected error:
one of 'for', 'parallel', 'sections' or 'taskgroup' is expected
Differential Revision: https://reviews.llvm.org/D30135
llvm-svn: 295808
We need to look through the PackExpansionType in the parameter type when
deducing, and we need to consider the possibility of deducing arguments for
packs that are not lexically mentioned in the pattern (but are nonetheless
deducible) when figuring out which packs are covered by a pack deduction scope.
llvm-svn: 295790
case where the class template has a parameter pack.
Checking of the template arguments expects an "as-written" template argument
list, which in particular does not have any parameter packs. So flatten the
packs into separate arguments before passing them in.
llvm-svn: 295710
template deduction guides for class template argument deduction.
Ensure that we have a local instantiation scope for tracking the instantiated
parameters. Additionally, unusually, we're substituting at depth 1 and leaving
depth 0 alone; make sure that we don't reduce template parameter depth by 2 for
inner parameters in the process. (This is probably also broken for alias
templates in the case where they're expanded within a dependent context, but
this patch doesn't fix that.)
llvm-svn: 295696
instantiation.
In preparation for converting the template stack to a more general context
stack (so we can include context notes for other kinds of context).
llvm-svn: 295686
Using the constructed name for the class properties with dot syntax may
yield an inappropriate selector (i.e. if it is specified via property
attributes). Prefer the declaration for the selector, falling back to
the constructed name otherwise.
Patch by David Herzka!
llvm-svn: 295683
These attributes effectively turn a non-defining declaration into a
definition, so the case when the declaration already has a body must
be diagnosed properly.
Differential Revision: https://reviews.llvm.org/D30032
llvm-svn: 295541
Reserve a spot for ODR hash in CXXRecordDecl and in its modules storage.
Default the hash value to 0 for all classes.
Differential Revision: https://reviews.llvm.org/D21675
llvm-svn: 295533
https://reviews.llvm.org/D29922
This patch adds two fields for use in the implementation of 'distribute parallel for':
The increment expression for the distribute loop. As the chunk assigned to a team is executed by multiple threads within the 'parallel for' region, the increment expression has to correspond to the value returned by the related runtime call (for_static_init).
The upper bound of the innermost loop ('for' in 'distribute parallel for') is not the globalUB expression normally used for pragma 'for' when found in isolation. It is instead the upper bound of the chunk assigned to the team ('distribute' loop). In this way, we prevent teams from executing chunks assigned to other teams.
The use of these two fields can be see in a related explanatory patch:
https://reviews.llvm.org/D29508
llvm-svn: 295497
A slightly weaker form of ODR checking than previous attempts, but hopefully
won't break the modules build bot. Future work will be needed to catch all
cases.
When objects are imported for modules, there is a chance that a name collision
will cause an ODR violation. Previously, only a small number of such
violations were detected. This patch provides a stronger check based on
AST nodes.
The information needed to uniquely identify an object is taken from the AST and
put into a one-dimensional byte stream. This stream is then hashed to give
a value to represent the object, which is stored with the other object data
in the module.
When modules are loaded, and Decl's are merged, the hash values of the two
Decl's are compared. Only Decl's with matched hash values will be merged.
Mismatch hashes will generate a module error, and if possible, point to the
first difference between the two objects.
The transform from AST to byte stream is a modified depth first algorithm.
Due to references between some AST nodes, a pure depth first algorithm could
generate loops. For Stmt nodes, a straight depth first processing occurs.
For Type and Decl nodes, they are replaced with an index number and only on
first visit will these nodes be processed. As an optimization, boolean
values are saved and stored together in reverse order at the end of the
byte stream to lower the ammount of data that needs to be hashed.
Compile time impact was measured at 1.5-2.0% during module building, and
negligible during builds without module building.
Differential Revision: https://reviews.llvm.org/D21675
llvm-svn: 295421
Removed ndrange_t as Clang builtin type and added
as a struct type in the OpenCL header.
Use type name to do the Sema checking in enqueue_kernel
and modify IR generation accordingly.
Review: D28058
Patch by Dmitry Borisenkov!
llvm-svn: 295311
Recommit r293585 that was reverted in r293611 with new fixes. The previous
issue was determined to be an overly aggressive AST visitor from forward
declared objects. The visitor will now only deeply visit certain Decl's and
only do a shallow information extraction from all other Decl's.
When objects are imported for modules, there is a chance that a name collision
will cause an ODR violation. Previously, only a small number of such
violations were detected. This patch provides a stronger check based on
AST nodes.
The information needed to uniquely identify an object is taken from the AST and
put into a one-dimensional byte stream. This stream is then hashed to give
a value to represent the object, which is stored with the other object data
in the module.
When modules are loaded, and Decl's are merged, the hash values of the two
Decl's are compared. Only Decl's with matched hash values will be merged.
Mismatch hashes will generate a module error, and if possible, point to the
first difference between the two objects.
The transform from AST to byte stream is a modified depth first algorithm.
Due to references between some AST nodes, a pure depth first algorithm could
generate loops. For Stmt nodes, a straight depth first processing occurs.
For Type and Decl nodes, they are replaced with an index number and only on
first visit will these nodes be processed. As an optimization, boolean
values are saved and stored together in reverse order at the end of the
byte stream to lower the ammount of data that needs to be hashed.
Compile time impact was measured at 1.5-2.0% during module building, and
negligible during builds without module building.
Differential Revision: https://reviews.llvm.org/D21675
llvm-svn: 295284
This appears to be the only template argument deduction context where we were
missing this check. Surprisingly, other implementations also appear to miss
the check in this case; it may turn out that important code is relying on
the widespread non-conformance here, in which case we'll need to reconsider.
llvm-svn: 295277
After r264564, we allowed direct-list-initialization of an enum from an
integral value in C++1z mode, so long as that value can convert to the
enum's underlying type.
In this kind of initialization, we need a lvalue-to-rvalue conversion
for the initializer value if it is not a rvalue. This lets us accept the
following code:
enum class A : unsigned {};
A foo(unsigned x) { return A{x}; }
Differential Revision: https://reviews.llvm.org/D29723
llvm-svn: 295266
r274291 made changes to prefer calling a move constructor to calling a
copy constructor when returning from a function. This caused programs to
crash when a __block variable in the heap was moved out and used later.
This commit fixes the bug by disallowing moving out of __block variables
implicitly.
rdar://problem/28181080
Differential Revision: https://reviews.llvm.org/D29908
llvm-svn: 295150
Summary: Previously the cleanups (e.g. dtor calls) are inserted into the
outer scope (e.g. function body scope), instead of it's own scope. After
the fix, the cleanups are inserted right after getting the size value.
This fixes pr30306.
Reviewers: rsmith
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D24333
llvm-svn: 295123
guide from a constructor.
The purpose of this change is to avoid triggering instantiation of the class
when substituting back into the deduction guide if it uses a typedef member.
We will still instantiate the class if the constructor (explicitly or
implicitly, directly or indirectly) uses the current instantiation in a way
that we can't canonicalize out, but that seems unavoidable.
llvm-svn: 295016
such guides below explicit ones, and ensure that references to the class's
template parameters are not treated as forwarding references.
We make a few tweaks to the wording in the current standard:
1) The constructor parameter list is copied faithfully to the deduction guide,
without losing default arguments or a varargs ellipsis (which the standard
wording loses by omission).
2) If the class template declares no constructors, we add a T() -> T<...> guide
(which will only ever work if T has default arguments for all non-pack
template parameters).
3) If the class template declares nothing that looks like a copy or move
constructor, we add a T(T<...>) -> T<...> guide.
#2 and #3 follow from the "pretend we had a class type with these constructors"
philosophy for deduction guides.
llvm-svn: 295007
This commit adds context sensitive code completion support for the C++11
keywords that currently don't have completion results.
The following keywords are supported by this patch:
alignas
constexpr
static_assert
noexcept (as a function/method qualifier)
thread_local
The following special identifiers are also supported:
final (as a method qualifier or class qualifier)
override
rdar://29219185
Differential Revision: https://reviews.llvm.org/D28286
llvm-svn: 295001
Summary:
Sema::CheckCompletedCoroutineBody was growing unwieldy with building all of the substatements. Also, constructors for CoroutineBodyStmt had way too many parameters.
Instead, CoroutineBodyStmt now defines CtorArgs structure with all of the required construction parameters.
CheckCompleteCoroutineBody delegates construction of individual substatements to short functions one per each substatement.
Also, added a drive-by fix of initializing CoroutinePromise to nullptr in ScopeInfo.h.
And addressed the FIXME that wanted to tail allocate extra room at the end of the CoroutineBodyStmt to hold parameter move expressions. (The comment was longer that the code that implemented tail allocation).
Reviewers: rsmith, EricWF
Subscribers: mehdi_amini, cfe-commits
Differential Revision: https://reviews.llvm.org/D28835
llvm-svn: 294933
...function type with a redeclaration having the same attribute. Fixing this
introduced a secondary problem where we were assuming that K&R functions
could not be attributed types when reporting old-style function definitions
that are not preceded by a prototype."
Also Revert "Hopefully fixes a compile error introduced by r294861."
This reverts commit r294862, r294861, as they bork the ARM builds and
haven't fix it back.
Also, please, short commit titles, long commit decsriptions...
llvm-svn: 294910
It's actually meaningful and useful to allow such variables to have no
initializer, but we are strictly following the standard here until the C++
committee reaches consensus on allowing this.
llvm-svn: 294785
Summary:
This adds associated constraints as a property of class templates.
An error is produced if redeclarations are not similarly constrained.
Reviewers: rsmith, faisalv, aaron.ballman
Reviewed By: rsmith
Subscribers: cfe-commits, nwilson
Differential Revision: https://reviews.llvm.org/D25674
llvm-svn: 294697
Summary:
This teaches clang how to parse and lower the 'interrupt' and 'naked'
attributes.
This allows interrupt signal handlers to be written.
Reviewers: aaron.ballman
Subscribers: malcolm.parsons, cfe-commits
Differential Revision: https://reviews.llvm.org/D28451
llvm-svn: 294402
Add a warning for shadowed variables across records. Referencing a
shadow'ed variable may not give the desired variable. Add an optional
warning for the shadowing.
Patch by James Sun!
llvm-svn: 294401
Fix for bug 30217 - incorrect error given for logical
NOT operation with a pointer type: corrected sema check
and improved related tests.
Review: D29038
llvm-svn: 294313
We model deduction-guides as functions with a new kind of name that identifies
the template whose deduction they guide; the bulk of this patch is adding the
new name kind. This gives us a clean way to attach an extensible list of guides
to a class template in a way that doesn't require any special handling in AST
files etc (and we're going to need these functions we come to performing
deduction).
llvm-svn: 294266
After r260016 and r260017 disabled typo correction for ivars and properties
clang didn't report errors about unresolved identifier in the base of ivar and
property ref expressions. This meant that clang invoked CodeGen on invalid AST
which then caused a crash.
This commit re-enables typo correction for ivars and properites, and fixes the
PR25113 & PR26486 (that were originally fixed in r260017 and r260016) in a
different manner by transforming the Objective-C ivar reference expression with
'IsFreeIvar' preserved.
rdar://30310772
llvm-svn: 294008
name. If the dependent name happened to end in a template-id (X<T>::Y<U>), we
would fail to notice that the 'typename' keyword is missing when resolving it
to a type.
It turns out that GCC has a similar bug. If this shows up in much real code, we
can easily downgrade this to an ExtWarn.
llvm-svn: 293815
For non-template dllimport functions, MSVC allows providing an inline
definition without spelling out the attribute again. In the example below, f
remains a dllimport function.
__declspec(dllimport) int f();
inline int f() { return 42; }
int useit() {
return f();
}
However, for a function template, not putting dllimport on the redeclaration
causes it to be dropped. In the example below, f is not dllimport.
template <typename> __declspec(dllimport) int f();
template <typename> inline int f() { return 42; }
int useit() {
return f<int>();
}
This patch makes Clang match MSVC for the second example.
MSVC does not warn about the attribute being dropped in the example above, but
I think we should. (MSVC does warn if the inline keyword isn't used.)
Differential Revision: https://reviews.llvm.org/D29152
llvm-svn: 293800
Contrary to the comment, DeclContext intends to guarantee that the lookup
results for a particular name will be stable across non-AST-mutating
operations, so a copy here should not be necessary. Further, if a copy *is*
necessary, the other four instances of this pattern within this file would also
be wrong, and we have no evidence of any problems with them; if this change
unearths problems, we should fix all the instances of this pattern.
llvm-svn: 293740
FindInstantiatedDecl or passing it to RebuildMemberExpr.
This fixes PR30361.
rdar://problem/17341274
Differential Revision: https://reviews.llvm.org/D24969
llvm-svn: 293678
My original warning was very conservative and I never revisited the
heuristics that were used.
This would have caught http://crbug.com/687251 at compile time.
llvm-svn: 293677
We're seeing what we believe are false positives. (It's hard to tell with the
available diagnostics, and I'm not sure how to reduce them yet).
I'll send Richard reproduction details offline.
djasper/chandlerc suggested this should be a warning for now, to make rolling it
out feasible.
llvm-svn: 293611
When objects are imported for modules, there is a chance that a name collision
will cause an ODR violation. Previously, only a small number of such
violations were detected. This patch provides a stronger check based on
AST nodes.
The information needed to uniquely identify an object is taked from the AST and
put into a one-dimensional byte stream. This stream is then hashed to give
a value to represent the object, which is stored with the other object data
in the module.
When modules are loaded, and Decl's are merged, the hash values of the two
Decl's are compared. Only Decl's with matched hash values will be merged.
Mismatch hashes will generate a module error, and if possible, point to the
first difference between the two objects.
The transform from AST to byte stream is a modified depth first algorithm.
Due to references between some AST nodes, a pure depth first algorithm could
generate loops. For Stmt nodes, a straight depth first processing occurs.
For Type and Decl nodes, they are replaced with an index number and only on
first visit will these nodes be processed. As an optimization, boolean
values are saved and stored together in reverse order at the end of the
byte stream to lower the ammount of data that needs to be hashed.
Compile time impact was measured at 1.5-2.0% during module building, and
negligible during builds without module building.
Differential Revision: https://reviews.llvm.org/D21675
llvm-svn: 293585
First pass at generating weak definitions of inline functions from module files
(& skipping (-O0) or emitting available_externally (optimizations)
definitions where those modules are used).
External functions defined in modules are emitted into the modular
object file as well (this may turn an existing ODR violation (if that
module were imported into multiple translations) into valid/linkable
code).
Internal symbols (static functions, for example) are not correctly
supported yet. The symbol will be produced, internal, in the modular
object - unreferenceable from the users.
Reviewers: rsmith
Differential Revision: https://reviews.llvm.org/D28845
llvm-svn: 293456
non-template function instantiated from a friend declaration in a class
template from TSK_ImplicitInstantiation to TSK_Undeclared.
It doesn't make sense for a non-template function to be flagged as being
instantiated from a template; that property really belongs to the entity
as a whole and not an individual declaration of it. There's some history
here:
* r137934 started marking these functions as instantiations in order to
work around an issue where we might instantiate a class template while
we're still parsing its member definitions, and would otherwise fail
to instantiate the friend definition
* r177003 fixed the same issue but for friend templates, but did so by
making the friends claim to be definitions even before we'd parsed
their actual bodies; this made the r137934 change redundant
* r293558 worked around a problem caused by the marking of a non-template
function as a template instantiation in r137934
This change reverts the code changes from r293358 and r137934 and retains
all the tests.
llvm-svn: 293367
This patch changes how we handle argument-dependent `diagnose_if`
attributes. In particular, we now check them in the same place that we
check for things like passing NULL to Nonnull args, etc. This is
basically better in every way than how we were handling them before. :)
This fixes PR31638, PR31639, and PR31640.
Differential Revision: https://reviews.llvm.org/D28889
llvm-svn: 293360
Modify ObjC blocks impl wrt address spaces as follows:
- keep default private address space for blocks generated
as local variables (with captures);
- add global address space for global block literals (no captures);
- make the block invoke function and enqueue_kernel prototype with
the generic AS block pointer parameter to accommodate both
private and global AS cases from above;
- add block handling into default AS because it's implemented as
a special pointer type (BlockPointer) in the frontend and therefore
it is used as a pointer everywhere. This is also needed to accommodate
both private and global AS blocks for the two cases above.
- removes ObjC RT specific symbols (NSConcreteStackBlock and
NSConcreteGlobalBlock) in the OpenCL mode.
Review: https://reviews.llvm.org/D28814
llvm-svn: 293286
This change adds a new type node, DeducedTemplateSpecializationType, to
represent a type template name that has been used as a type. This is modeled
around AutoType, and shares a common base class for representing a deduced
placeholder type.
We allow deduced class template types in a few more places than the standard
does: in conditions and for-range-declarators, and in new-type-ids. This is
consistent with GCC and with discussion on the core reflector. This patch
does not yet support deduced class template types being named in typename
specifiers.
llvm-svn: 293207
even in the presence of nullability qualifiers.
This commit fixes bugs in r285031 where -Wblock-capture-autoreleasing
wouldn't issue warnings when the function parameters were annotated
with nullability qualifiers. Specifically, look through the sugar and
see if there is an AttributedType of kind attr_objc_ownership to
determine whether __autoreleasing was explicitly specified or implicitly
added by the compiler.
rdar://problem/30193488
llvm-svn: 293194
The thread_limit-clause on the combined directive applies to the
'teams' region of this construct. We modify the ThreadLimitClause
class to capture the clause expression within the 'target' region.
Reviewers: ABataev
Differential Revision: https://reviews.llvm.org/D29087
llvm-svn: 293049
The num_teams-clause on the combined directive applies to the
'teams' region of this construct. We modify the NumTeamsClause
class to capture the clause expression within the 'target' region.
Reviewers: ABataev
Differential Revision: https://reviews.llvm.org/D29085
llvm-svn: 293048
This patch adds support for codegen of 'target teams' on the host.
This combined directive has two captured statements, one for the
'teams' region, and the other for the 'parallel'.
This target teams region is offloaded using the __tgt_target_teams()
call. The patch sets the number of teams as an argument to
this call.
Reviewers: ABataev
Differential Revision: https://reviews.llvm.org/D29084
llvm-svn: 293005
This patch adds support for codegen of 'target teams' on the host.
This combined directive has two captured statements, one for the
'teams' region, and the other for the 'parallel'.
This target teams region is offloaded using the __tgt_target_teams()
call. The patch sets the number of teams as an argument to
this call.
Reviewers: ABataev
Differential Revision: https://reviews.llvm.org/D29084
llvm-svn: 293001
The num_threads-clause on the combined directive applies to the
'parallel' region of this construct. We modify the NumThreadsClause
class to capture the clause expression within the 'target' region.
The offload runtime call for 'target parallel' is changed to
__tgt_target_teams() with 1 team and the number of threads set by
this clause or a default if none.
Reviewers: ABataev
Differential Revision: https://reviews.llvm.org/D29082
llvm-svn: 292997
methods from protocols and categories as well
Code completion results for class methods already include instance methods
from Objective-C root classes. This commit ensures that the results also include
instance methods from protocols that the root class implements and root class
categories as well.
rdar://28012953
Differential Revision: https://reviews.llvm.org/D27257
llvm-svn: 292932
The DSAChecker code in SemaOpenMP looks at the captured statement
associated with an OpenMP directive. A combined directive such as
'target parallel' has nested capture statements, which have to be
fully traversed before executing the DSAChecker. This is a patch
to perform the traversal for such combined directives.
Reviewers: ABataev
Differential Revision: https://reviews.llvm.org/D29026
llvm-svn: 292794
This commit improves the mismatched destructor type error by detecting when the
destructor call has used a '.' instead of a '->' on a pointer to the destructed
type. The diagnostic now suggests to use '->' instead of '.', and adds a fixit
where appropriate.
rdar://28766702
Differential Revision: https://reviews.llvm.org/D25817
llvm-svn: 292615
Under this defect resolution, the injected-class-name of a class or class
template cannot be used except in very limited circumstances (when declaring a
constructor, in a nested-name-specifier, in a base-specifier, or in an
elaborated-type-specifier). This is apparently done to make parsing easier, but
it's a pain for us since we don't know whether a template-id using the
injected-class-name is valid at the point when we annotate it (we don't yet
know whether the template-id will become part of an elaborated-type-specifier).
As a tentative resolution to a perceived language defect, mem-initializer-ids
are added to the list of exceptions here (they generally follow the same rules
as base-specifiers).
When the reference to the injected-class-name uses the 'typename' or 'template'
keywords, we permit it to be used to name a type or template as an extension;
other compilers also accept some cases in this area. There are also a couple of
corner cases with dependent template names that we do not yet diagnose, but
which will also get this treatment.
llvm-svn: 292518
The if-clause on the combined directive potentially applies to both the
'target' and the 'parallel' regions. Codegen'ing the if-clause on the
combined directive requires additional support because the expression in
the clause must be captured by the 'target' capture statement but not
the 'parallel' capture statement. Note that this situation arises for
other clauses such as num_threads.
The OMPIfClause class inherits OMPClauseWithPreInit to support capturing
of expressions in the clause. A member CaptureRegion is added to
OMPClauseWithPreInit to indicate which captured statement (in this case
'target' but not 'parallel') captures these expressions.
To ensure correct codegen of captured expressions in the presence of
combined 'target' directives, OMPParallelScope was added to 'parallel'
codegen.
Reviewers: ABataev
Differential Revision: https://reviews.llvm.org/D28781
llvm-svn: 292437
This rule permits the injected-class-name of a class template to be used as
both a template type argument and a template template argument, with no extra
syntax required to disambiguate.
llvm-svn: 292426
This patch adds support for codegen of 'target parallel' on the host.
It is also the first combined directive that requires two or more
captured statements. Support for this functionality is included in
the patch.
A combined directive such as 'target parallel' has two captured
statements, one for the 'target' and the other for the 'parallel'
region. Two captured statements are required because each has
different implicit parameters (see SemaOpenMP.cpp). For example,
the 'parallel' has 'global_tid' and 'bound_tid' while the 'target'
does not. The patch adds support for handling multiple captured
statements based on the combined directive.
When codegen'ing the 'target parallel' directive, the 'target'
outlined function is created using the outer captured statement
and the 'parallel' outlined function is created using the inner
captured statement.
Reviewers: ABataev
Differential Revision: https://reviews.llvm.org/D28753
llvm-svn: 292419
The idea for this originated from a really tricky bug: ISRs on ARM don't
automatically save off the VFP regs, so if say, memcpy gets interrupted and the
ISR itself calls memcpy, the regs are left clobbered when the ISR is done.
https://reviews.llvm.org/D28820
llvm-svn: 292375
This patch adds support for codegen of 'target parallel' on the host.
It is also the first combined directive that requires two or more
captured statements. Support for this functionality is included in
the patch.
A combined directive such as 'target parallel' has two captured
statements, one for the 'target' and the other for the 'parallel'
region. Two captured statements are required because each has
different implicit parameters (see SemaOpenMP.cpp). For example,
the 'parallel' has 'global_tid' and 'bound_tid' while the 'target'
does not. The patch adds support for handling multiple captured
statements based on the combined directive.
When codegen'ing the 'target parallel' directive, the 'target'
outlined function is created using the outer captured statement
and the 'parallel' outlined function is created using the inner
captured statement.
Reviewers: ABataev
Differential Revision: https://reviews.llvm.org/D28753
llvm-svn: 292374
CheckDesignatedInitializer wasn't taking into account the base classes
when computing the index for the field in the derived class, which
caused the test case to crash during IRGen because of a malformed AST.
rdar://problem/26795040
Differential Revision: https://reviews.llvm.org/D28705
llvm-svn: 292245
The rules around typechecking deduced template arguments during partial
ordering are not clear, and while the prior behavior does not seem to be
correct (it doesn't follow the general model of partial ordering where each
template parameter is replaced by a non-dependent but unique value), the new
behavior is also not clearly right and breaks some existing idioms.
The new behavior is retained for dealing with non-type template parameters
with 'auto' types, as without it even the most basic uses of that feature
don't work. We can revisit this once CWG has come to an agreement on how
partial ordering with 'auto' non-type template parameters is supposed to
work.
llvm-svn: 292183
Summary:
Warn when a lambda explicitly captures something that is not used in its body.
The warning is part of -Wunused and can be enabled with -Wunused-lambda-capture.
Reviewers: rsmith, arphaman, jbcoe, aaron.ballman
Subscribers: Quuxplusone, arphaman, cfe-commits
Differential Revision: https://reviews.llvm.org/D28467
llvm-svn: 291905
Diasllow a declaration using the 'auto' type specifier from using two different
meanings of it at once, or from declaring multiple functions with deduced
return types or introducing multiple trailing return types.
The standard does not technically disallow the multiple trailing return types
case if all the declarators declare variables (such as function pointers with
trailing return types), but we disallow that too, following the clear intent.
llvm-svn: 291880
In the case where the template class itself is already `dllexport`, the
implicit instantiation will have already emitted all members. When we
check the explicit instantiation definition, the `Specialization` will
have inherited the `dllexport` attribute, so we'll attempt to emit all
members for a second time, which causes an assertion failure. Restrict
the exporting to when the `dllexport` attribute is newly introduced by
the explicit instantiation definition.
Fixes PR31608.
Differential Revision: https://reviews.llvm.org/D28590
llvm-svn: 291877
Summary:
We do not currently track the source locations for exception specifications such
that their source range can be queried through the AST. This leads to trying to
write more complex code to determine the source range for uses like FixItHints
(see D18575 for an example). In addition to use within tools like clang-tidy, I
think this information may become more important to track as exception
specifications become more integrated into the type system.
Patch by Don Hinton.
Reviewers: rsmith
Subscribers: malcolm.parsons, sbarzowski, alexfh, hintonda, cfe-commits
Differential Revision: https://reviews.llvm.org/D20428
llvm-svn: 291771
the same source range and use the unary operator fixit only when it
actually silences the warning.
rdar://24570531
Differential Revision: https://reviews.llvm.org/D28231
llvm-svn: 291757
Fixes a crash in modules where the template class decl becomes the most recent
decl in the redeclaration chain and forcing the template instantiator try to
instantiate the friend declaration, rather than the template definition.
In practice, A::list<int> produces a TemplateSpecializationType
A::__1::list<int, allocator<type-parameter-0-0> >' failing to replace to
subsitute the default argument to allocator<int>.
Kudos Richard Smith (D28399).
llvm-svn: 291753
This flag serves no purpose other than to prevent us walking through a type to
check whether it contains an 'auto' specifier; this duplication of information
is error-prone, does not appear to provide any performance benefit, and will
become less practical once we support C++1z deduced class template types and
eventually constrained types from the Concepts TS.
No functionality change intended.
llvm-svn: 291737
filter out the implicilty imported modules at CodeGen instead of removing the
implicit ImportDecl when an implementation TU of a module imports a header of
that same module.
llvm-svn: 291688
This patch is to implement sema and parsing for 'target teams distribute simd’ pragma.
Differential Revision: https://reviews.llvm.org/D28252
llvm-svn: 291579
This commit ensures that clang avoids the redundant -Wshadow warning for
variables that already get a "redefinition of " error.
rdar://29067894
Differential Revision: https://reviews.llvm.org/D28350
llvm-svn: 291564
Don't prematurely clean up an RAII object; there's another RAII object in the
same scope that tries to save and restore the same member!
llvm-svn: 291551
This patch is to add support of the 'is_device_ptr' clause with the 'target parallel for' pragma.
Differential Revision: https://reviews.llvm.org/D28255
llvm-svn: 291540
This patch is to add support of the 'is_device_ptr' clause with the 'target parallel for simd' pragma.
Differential Revision: https://reviews.llvm.org/D28402
llvm-svn: 291537
properly even when a non-type template parameter has a dependent type.
Previously, if a non-type template parameter was dependent, but not dependent
on an outer level of template parameter, we would not match the type of the
parameter. Under [temp.arg.template], we are supposed to check that the types
are equivalent, which means checking for syntactic equivalence in the dependent
case.
This also fixes some accepts-invalids when passing templates with auto-typed
non-type template parameters as template template arguments.
llvm-svn: 291512
Fixes a regression introduced in r291045, which would lead to link
errors. While we should no longer encounter unparsed or uninstantiated
default arguments in this codepath, we still need to call
CheckCXXDefaultArgExpr to mark the default argument expressions as
ODR-used.
llvm-svn: 291453
Check for implicit conversion sequences for non-dependent function
template parameters between deduction and substitution. The idea is to accept
as many cases as possible, on the basis that substitution failure outside the
immediate context is much more common during substitution than during implicit
conversion sequence formation.
This re-commits r290808, reverted in r290811 and r291412, with a couple of
fixes for handling of explicitly-specified non-trailing template argument
packs.
llvm-svn: 291427
This issue clarifies how deduction proceeds past a non-trailing function
parameter pack. Essentially, the pack itself is skipped and consumes no
arguments (except for those implied by an explicitly-specified template
arguments), and nothing is deduced from it. As a small fix to the standard's
rule, we do not allow subsequent deduction to change the length of the function
parameter pack (by preventing extension of the explicitly-specified pack if
present, and otherwise deducing all contained packs to empty packs).
llvm-svn: 291425
`diagnose_if` can be used to have clang emit either warnings or errors
for function calls that meet user-specified conditions. For example:
```
constexpr int foo(int a)
__attribute__((diagnose_if(a > 10, "configurations with a > 10 are "
"expensive.", "warning")));
int f1 = foo(9);
int f2 = foo(10); // warning: configuration with a > 10 are expensive.
int f3 = foo(f2);
```
It currently only emits diagnostics in cases where the condition is
guaranteed to always be true. So, the following code will emit no
warnings:
```
constexpr int bar(int a) {
foo(a);
return 0;
}
constexpr int i = bar(10);
```
We hope to support optionally emitting diagnostics for cases like that
(and emitting runtime checks) in the future.
Release notes will appear shortly. :)
Differential Revision: https://reviews.llvm.org/D27424
llvm-svn: 291418
Add a visitor for lambda expressions to RecordExprEvaluator in ExprConstant.cpp that creates an empty APValue of Struct type to represent the closure object. Additionally, add a LambdaExpr visitor to the TemporaryExprEvaluator that forwards constant evaluation of immediately-called-lambda-expressions to the one in RecordExprEvaluator through VisitConstructExpr.
This patch supports:
constexpr auto ID = [] (auto a) { return a; };
static_assert(ID(3.14) == 3.14);
static_assert([](auto a) { return a + 1; }(10) == 11);
Lambda captures are still not supported for constexpr lambdas.
llvm-svn: 291416
Check for implicit conversion sequences for non-dependent function
template parameters between deduction and substitution. The idea is to accept
as many cases as possible, on the basis that substitution failure outside the
immediate context is much more common during substitution than during implicit
conversion sequence formation.
This re-commits r290808, reverted in r290811, with a fix for handling of
explicitly-specified template argument packs.
llvm-svn: 291410
deduction in partial ordering.
This prevents us from crashing due to attempting to instantiate the same class
template specialization definition multiple times. (Debug builds also appear to
sometimes hit the stack limit before hitting the instantiation depth limit in
this case.)
llvm-svn: 291407
The rule we use is that a construction of a class type T from an argument of
type U cannot use an inherited constructor if U is the same as T or is derived
from T (or if the initialization would first convert it to such a type). This
(approximately) matches the rule in use by GCC, and matches the current proposed
DR resolution.
llvm-svn: 291403
This patch has been sitting in review hell since july 2016 and our lack of constexpr lambda support is getting embarrassing (given that I've had a branch that implements the feature (modulo *this capture) for over a year. While in Issaquah I was enjoying shamelessly trying to convince folks of the lie that this was Richard's fault ;) I won't be able to do so in Kona since I won't be attending - so I'm going to aim to have this feature be implemented by then.
I'm quite confident of the approach in this patch, which simply maps the static-invoker 'thunk' back to the corresponding call-operator (specialization).
Thanks!
llvm-svn: 291397
This implements something like the current direction of DR1581: we use a narrow
syntactic check to determine the set of places where a constant expression
could be evaluated, and only instantiate a constexpr function or variable if
it's referenced in one of those contexts, or is odr-used.
It's not yet clear whether this is the right set of syntactic locations; we
currently consider all contexts within templates that would result in odr-uses
after instantiation, and contexts within list-initialization (narrowing
conversions take another victim...), as requiring instantiation. We could in
principle restrict the former cases more (only const integral / reference
variable initializers, and contexts in which a constant expression is required,
perhaps). However, this is sufficient to allow us to accept libstdc++ code,
which relies on GCC's behavior (which appears to be somewhat similar to this
approach).
llvm-svn: 291318
dependent context and can't be used in a constant expression.
Per C++ [temp.inst]p2, "the instantiation of a static data member does not
occur unless the static data member is used in a way that requires the
definition to exist".
This doesn't /quite/ match that, as we still instantiate static data members
that are usable in constant expressions even if the use doesn't require a
definition. A followup patch will fix that for both variables and functions.
llvm-svn: 291295
Now when completing blocks properties that return void the block call completion
result shows up before the setter, otherwise the setter completion shows up
before the block call completion. We normally want to use the result of the
block call, so one typically wouldn't call a block that returns a non-void type
in a standalone statement.
rdar://28846153
Differential Revision: https://reviews.llvm.org/D26034
llvm-svn: 291232
We were previously incorrectly using TDK_TooFewArguments to report a template
argument list that's too short, but it actually means that the number of
arguments in a top-level function call was insufficient. When diagnosing the
problem, SemaOverload would (rightly) assert that the failure kind didn't make
any sense.
llvm-svn: 291064
Summary:
Replace some old code that probably pre-dated the change to delay
emission of dllexported code until after the closing brace of the
outermost record type. Only uninstantiated default argument expressions
need to be handled now. It is enough to instantiate default argument
expressions when instantiating dllexported default ctors. This also
fixes some double-diagnostic issues in this area.
Fixes PR31500
Reviewers: rsmith
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D28274
llvm-svn: 291045
Most code paths would already bail out in this case, but certain paths,
particularly overload resolution and typo correction, would not. Carrying on
with an invalid declaration could in some cases result in crashes due to
downstream code relying on declaration invariants that are not necessarily
met for invalid declarations, and in other cases just resulted in undesirable
follow-on diagnostics.
llvm-svn: 291030
Previously, if an overloaded function in a braced-init-list was encountered in
template argument deduction, and the overload set couldn't be resolved to a
particular function, we'd immediately produce a deduction failure. That's not
correct; this situation is supposed to result in that particular P/A pair being
treated as a non-deduced context, and deduction can still succeed if the type
can be deduced from elsewhere.
llvm-svn: 291014
Previously, if the arguments for a parameter pack contained a braced-init-list,
we would abort deduction (keeping the pack deductions from prior arguments) at
the point when we reached the braced-init-list, resulting in wrong deductions
and rejects-valids. We now just leave a "hole" in the pack for such an argument,
which needs to be filled by another deduction of the same pack.
llvm-svn: 290933
When a parameter pack has multiple corresponding arguments, and some subset of
them are overloaded functions, it's possible that some subset of the parameters
are non-deduced contexts. In such a case, keep deducing from the remainder of
the arguments, and resolve the incomplete pack against whatever other
deductions we've performed for the pack.
GCC, MSVC, and ICC give three different bad behaviors for this case; what we do
now (and what we did before) don't exactly match any of them, sadly :( I'm
getting a core issue opened to specify more precisely how this should be
handled.
llvm-svn: 290923
This patch is to implement sema and parsing for 'target teams distribute parallel for simd’ pragma.
Differential Revision: https://reviews.llvm.org/D28202
llvm-svn: 290862
In many translation units I have tried, the calls to isIgnored() removed
in this patch are more expensive than doing the analysis that is behind
it. The speed-up in translation units I have tried is between 10 and
20%.
Review: https://reviews.llvm.org/D28208
llvm-svn: 290842
This reverts commit r290808, as it broken all ARM and AArch64 test-suite
test: MultiSource/UnitTests/C++11/frame_layout
Also, please, next time, try to write a commit message in according to
our guidelines:
http://llvm.org/docs/DeveloperPolicy.html#commit-messages
llvm-svn: 290811
template parameters between deduction and substitution. The idea is to accept
as many cases as possible, on the basis that substitution failure outside
the immediate context is much more common during substitution than during
implicit conversion sequence formation.
This does not implement the partial ordering portion of DR1391, which so
far appears to be misguided.
llvm-svn: 290808
to be specified for a template template parameter whenever the parameter is at
least as specialized as the argument (when there's an obvious and correct
mapping from uses of the parameter to uses of the argument). For example, a
template with more parameters can be passed to a template template parameter
with fewer, if those trailing parameters have default arguments.
This is disabled by default, despite being a DR resolution, as it's fairly
broken in its current state: there are no partial ordering rules to cope with
template template parameters that have different parameter lists, meaning that
code that attempts to decompose template-ids based on arity can hit unavoidable
ambiguity issues.
The diagnostics produced on a non-matching argument are also pretty bad right
now, but I aim to improve them in a subsequent commit.
llvm-svn: 290792
This patch is to implement sema and parsing for 'target teams distribute parallel for’ pragma.
Differential Revision: https://reviews.llvm.org/D28160
llvm-svn: 290725
to make reference to template parameters. This is only a partial
implementation; we retain the restriction that the argument must not be
type-dependent, since it's unclear how that would work given the existence of
other language rules requiring an exact type match in this context, even for
type-dependent cases (a question has been raised on the core reflector).
llvm-svn: 290647
specialized than the primary template. (Put another way, if we imagine there
were a partial specialization matching the primary template, we should never
select it if some other partial specialization also matches.)
llvm-svn: 290593
template parameters of reference type basically doesn't work, because we're
always deducing from an argument expression of non-reference type, so the type
of the deduced expression never matches. Instead, compare the type of an
expression naming the parameter to the type of the argument.
llvm-svn: 290586
dependent contexts when processing the template in C++11 and C++14, just like
we do in C++98 and C++1z. This allows us to diagnose invalid templates earlier.
llvm-svn: 290567
According to extended asm syntax, a case where the clobber list includes a variable from the inputs or outputs should be an error - conflict.
for example:
const long double a = 0.0;
int main()
{
char b;
double t1 = a;
__asm__ ("fucompp": "=a" (b) : "u" (t1), "t" (t1) : "cc", "st", "st(1)");
return 0;
}
This should conflict with the output - t1 which is st, and st which is st aswell.
The patch fixes it.
Commit on behald of Ziv Izhar.
Differential Revision: https://reviews.llvm.org/D15075
llvm-svn: 290539
non-type template parameters.
During partial ordering, when checking the substituted deduced template
arguments match the original, check the types of non-type template arguments
match even if they're dependent. The only way we get dependent types here is if
they really represent types of the other template (which are supposed to be
modeled as being substituted for unique, non-dependent types).
In order to make this work for auto-typed non-type template arguments, we need
to be able to perform auto deduction even when the initializer and
(potentially) the auto type are dependent, support for which is the bulk of
this patch. (Note that this requires the ability to deduce only a single level
of a multi-level dependent type.)
llvm-svn: 290511
This patch is to implement sema and parsing for 'target teams distribute' pragma.
Differential Revision: https://reviews.llvm.org/D28015
llvm-svn: 290508
template arguments as written rather than the canonical template arguments,
so we print more user-friendly names for template parameters.
llvm-svn: 290483
twice, in finalization of template argument deduction.
This is a re-commit of r290310 (reverted in r290329); the bug found by the
buildbots was fixed in r290399 (we would sometimes build a deduced template
argument with a bogus type).
llvm-svn: 290403
fail the merge if the arguments have different types (except if one of them was
deduced from an array bound, in which case take the type from the other).
This is correct because (except in the array bound case) the type of the
template argument in each deduction must match the type of the parameter, so at
least one of the two deduced arguments must have a mismatched type.
This is necessary because we would otherwise lose the type information for the
discarded template argument in the merge, and fail to diagnose the mismatch.
In order to power this, we now properly retain the type of a deduced non-type
template argument deduced from a declaration, rather than giving it the type of
the template parameter; we'll convert it to the template parameter type when
checking the deduced arguments.
llvm-svn: 290399
Print the fully qualified names for the overload candidates. This makes
it easier to tell what the ambiguity is. Especially if a template
is instantiated after a using namespace, it will not inherit the
namespace where it was declared. The specialization will give a message
about a partial order being ambiguous for the same (unqualified) name,
which does not help identify the failure.
Addresses PR31450!
llvm-svn: 290315
This is a recommit of r290149, which was reverted in r290169 due to msan
failures. msan was failing because we were calling
`isMostDerivedAnUnsizedArray` on an invalid designator, which caused us
to read uninitialized memory. To fix this, the logic of the caller of
said function was simplified, and we now have a `!Invalid` assert in
`isMostDerivedAnUnsizedArray`, so we can catch this particular bug more
easily in the future.
Fingers crossed that this patch sticks this time. :)
Original commit message:
This patch does three things:
- Gives us the alloc_size attribute in clang, which lets us infer the
number of bytes handed back to us by malloc/realloc/calloc/any user
functions that act in a similar manner.
- Teaches our constexpr evaluator that evaluating some `const` variables
is OK sometimes. This is why we have a change in
test/SemaCXX/constant-expression-cxx11.cpp and other seemingly
unrelated tests. Richard Smith okay'ed this idea some time ago in
person.
- Uniques some Blocks in CodeGen, which was reviewed separately at
D26410. Lack of uniquing only really shows up as a problem when
combined with our new eagerness in the face of const.
llvm-svn: 290297
argument even if the expression is value-dependent (we need to suppress the
final portion of the narrowing check, but the rest of the checking can still be
done eagerly).
This affects template template argument validity and partial ordering under
p0522r0.
llvm-svn: 290276
effect they would have in C++11. In particular, they do not prevent
value-initialization from performing zero-initialization, nor do they prevent a
struct from being an aggregate.
llvm-svn: 290229
function. (This change would also allow us to handle default template arguments
in partial specializations if the standard ever permits them.)
llvm-svn: 290225
This change introduces UsingPackDecl as a marker for the set of UsingDecls
produced by pack expansion of a single (unresolved) using declaration. This is
not strictly necessary (we just need to be able to map from the original using
declaration to its expansions somehow), but it's useful to maintain the
invariant that each declaration reference instantiates to refer to one
declaration.
This is a re-commit of r290080 (reverted in r290092) with a fix for a
use-after-lifetime bug.
llvm-svn: 290203
based coverage compilation
Added source location info to captured expression declaration + fixed
source location info for loop based directives.
llvm-svn: 290181
This reverts commit r290171. It triggers a bunch of warnings, because
the new enumerator isn't handled in all switches. We want a warning-free
build.
Replied on the commit with more details.
llvm-svn: 290173
Summary: Enabling the compression of CLK_NULL_QUEUE to variable of type queue_t.
Reviewers: Anastasia
Subscribers: cfe-commits, yaxunl, bader
Differential Revision: https://reviews.llvm.org/D27569
llvm-svn: 290171
This commit fails MSan when running test/CodeGen/object-size.c in
a confusing way. After some discussion with George, it isn't really
clear what is going on here. We can make the MSan failure go away by
testing for the invalid bit, but *why* things are invalid isn't clear.
And yet, other code in the surrounding area is doing precisely this and
testing for invalid.
George is going to take a closer look at this to better understand the
nature of the failure and recommit it, for now backing it out to clean
up MSan builds.
llvm-svn: 290169
This patch does three things:
- Gives us the alloc_size attribute in clang, which lets us infer the
number of bytes handed back to us by malloc/realloc/calloc/any user
functions that act in a similar manner.
- Teaches our constexpr evaluator that evaluating some `const` variables
is OK sometimes. This is why we have a change in
test/SemaCXX/constant-expression-cxx11.cpp and other seemingly
unrelated tests. Richard Smith okay'ed this idea some time ago in
person.
- Uniques some Blocks in CodeGen, which was reviewed separately at
D26410. Lack of uniquing only really shows up as a problem when
combined with our new eagerness in the face of const.
Differential Revision: https://reviews.llvm.org/D14274
llvm-svn: 290149
* In C++, never create a FunctionNoProtoType for a builtin (fixes C++1z
crasher from r289754).
* Fix type of __sync_synchronize to be a no-parameter function rather than a
varargs function. This matches GCC.
* Fix type of vfprintf to match its actual type. We gave it a wrong type due
to PR4290 (apparently autoconf generates invalid code and expects compilers
to choke it down or it miscompiles the program; the relevant error in clang
was downgraded to a warning in r122744 to fix other occurrences of this
autoconf brokenness, so we don't need this workaround any more).
* Turn off vararg argument checking for __noop, since it's not *really* a
varargs function. Alternatively we could add custom type checking for it
and synthesize parameter types matching the actual arguments in each call,
but that seemed like overkill.
llvm-svn: 290146
The newly-added notes from r290132 are too noisy even when the fix-it
is valid. For the existing warning from r286521, it's probably the
right decision 95% of the time to put the change outside the macro if
the array is outside the macro and inside otherwise, but I don't want
to overthink it right now.
Caught by the ASan bot!
More rdar://problem/29524992
llvm-svn: 290141
This is especially important for arrays, since no one knows the proper
syntax for putting qualifiers in arrays.
nullability.h:3:26: warning: array parameter is missing a nullability type specifier (_Nonnull, _Nullable, or _Null_unspecified)
void arrayParameter(int x[]);
^
nullability.h:3:26: note: insert '_Nullable' if the array parameter may be null
void arrayParameter(int x[]);
^
_Nullable
nullability.h:3:26: note: insert '_Nonnull' if the array parameter should never be null
void arrayParameter(int x[]);
^
_Nonnull
rdar://problem/29524992
llvm-svn: 290132
This change introduces UsingPackDecl as a marker for the set of UsingDecls
produced by pack expansion of a single (unresolved) using declaration. This is
not strictly necessary (we just need to be able to map from the original using
declaration to its expansions somehow), but it's useful to maintain the
invariant that each declaration reference instantiates to refer to one
declaration.
llvm-svn: 290080
* a dependent non-type using-declaration within a function template can be
valid, as it can refer to an enumerator, so don't reject it in the template
definition
* we can partially substitute into a dependent using-declaration if it appears
within a (local class in a) generic lambda within a function template, which
means an UnresolvedUsing*Decl doesn't necessarily instantiate to a UsingDecl.
llvm-svn: 290071
lambda expression is instantiated.
Rather than waiting until Sema::CheckCXXDefaultArgExpr tries to
transform the default arguments (which fails because it can't get the
template arguments that are used), transform the default arguments
earlier when the lambda expression is transformed in
TransformLambdaExpr.
rdar://problem/27535319
Differential Revision: https://reviews.llvm.org/D23096
llvm-svn: 289990
This patch is to add support of the 'is_device_ptr' clause in the 'target parallel' pragma.
Differential Revision: https://reviews.llvm.org/D27821
llvm-svn: 289989
Added a map to associate types and declarations with extensions.
Refactored existing diagnostic for disabled types associated with extensions and extended it to declarations for generic situation.
Fixed some bugs for types associated with extensions.
Allow users to use pragma to declare types and functions for supported extensions, e.g.
#pragma OPENCL EXTENSION the_new_extension_name : begin
// declare types and functions associated with the extension here
#pragma OPENCL EXTENSION the_new_extension_name : end
Differential Revision: https://reviews.llvm.org/D21698
llvm-svn: 289979
expressions in a function or class template.
This patch makes the following changes:
- Create a DependentScopeDeclRefExpr for the default argument instead of
a CXXDependentScopeMemberExpr.
- Pass CombineWithOuterScope=true so that the outer scope in which the
enum is declared is searched for the instantiation of the enum.
This is the first part of https://reviews.llvm.org/D23096. Fixes PR28795
rdar://problem/27535319
llvm-svn: 289914
constructs that can do so into the initialization code. This fixes a number
of different cases in which we used to fail to check for abstract types.
Thanks to Tim Shen for inspiring the weird code that uncovered this!
llvm-svn: 289753
r289225 broke AST invariants by reparenting enumerators into function
decl contexts. This improves things by only reparenting TagDecls while
also attempting to preserve the lexical declcontext chain. The
interesting example here is:
int f(struct S { enum E { a = 1 } b; } c);
The semantic contexts of E and S should be f, and the lexical context of
S should be f and the lexical context of E should be S. We didn't do
that with r289225, but now we should.
This change should also improve our behavior on this example:
void f() {
extern void ext(struct S { } o);
// S injected here
}
Before r289225 we would only remove 'S' from the surrounding tag
injection context if it was the TU, but now we properly reparent S from
f to ext.
Fixes PR31366
llvm-svn: 289678
The function SemaBuiltinFPClassification removed superfluous float to double
casts, this was changed to also remove float to float casts but this isn't
valid in all cases, for example when doing an rvaluetolvalue cast. Added a
check to only remove if this was a conventional floating cast.
Added additional tests into SemaOpenCL/extensions to cover these cases
llvm-svn: 289650
At least the plugin used by the LibreOffice build
(<https://wiki.documentfoundation.org/Development/Clang_plugins>) indirectly
uses those members (through inline functions in LLVM/Clang include files in turn
using them), but they are not exported by utils/extract_symbols.py on Windows,
and accessing data across DLL/EXE boundaries on Windows is generally
problematic.
Differential Revision: https://reviews.llvm.org/D26671
llvm-svn: 289647
copy constructors of classes with array members, instead using
ArrayInitLoopExpr to represent the initialization loop.
This exposed a bug in the static analyzer where it was unable to differentiate
between zero-initialized and unknown array values, which has also been fixed
here.
llvm-svn: 289618
Although not specifically mentioned in the documentation, MSVC accepts
__uuidof(…) and declspec(uuid("…")) attributes on enumeration types in
addition to structs/classes. This is meaningful, as such types *do* have
associated UUIDs in ActiveX typelibs, and such attributes are included
by default in the wrappers generated by their #import construct, so they
are not particularly unusual.
clang currently rejects the declspec with a –Wignored-attributes
warning, and errors on __uuidof() with “cannot call operator __uuidof on
a type with no GUID” (because it rejected the uuid attribute, and
therefore finds no value). This is causing problems for us while trying
to use clang-tidy on a codebase that makes heavy use of ActiveX.
I believe I have found the relevant places to add this functionality,
this patch adds this case to clang’s implementation of these MS
extensions. patch is against r285994 (or actually the git mirror
80464680ce).
Both include an update to test/Parser/MicrosoftExtensions.cpp to
exercise the new functionality.
This is my first time contributing to LLVM, so if I’ve missed anything
else needed to prepare this for review just let me know!
__uuidof: https://msdn.microsoft.com/en-us/library/zaah6a61.aspx
declspec(uuid("…")): https://msdn.microsoft.com/en-us/library/3b6wkewa.aspx
#import: https://msdn.microsoft.com/en-us/library/8etzzkb6.aspx
Reviewers: aaron.ballman, majnemer, rnk
Differential Revision: https://reviews.llvm.org/D26846
llvm-svn: 289567