Commit Graph

1748 Commits

Author SHA1 Message Date
Volodymyr Sapsai 65f58878e7 [ObjC generics] Fix not inheriting type bounds in categories/extensions.
When a category/extension doesn't repeat a type bound, corresponding
type parameter is substituted with `id` when used as a type argument. As
a result, in the added test case it was causing errors like

> type argument 'T' (aka 'id') does not satisfy the bound ('id<NSCopying>') of type parameter 'T'

We are already checking that type parameters should be consistent
everywhere (see `checkTypeParamListConsistency`) and update
`ObjCTypeParamDecl` to have correct underlying type. And when we use the
type parameter as a method return type or a method parameter type, it is
substituted to the bounded type. But when we use the type parameter as a
type argument, we check `ObjCTypeParamType` that wasn't updated and
remains `id`.

Fix by updating not only `ObjCTypeParamDecl` UnderlyingType but also
TypeForDecl as we use the underlying type to create a canonical type for
`ObjCTypeParamType` (see `ASTContext::getObjCTypeParamType`).

This is a different approach to fixing the issue. The previous one was
02c2ab3d88 which was reverted in
4c539e8da1. The problem with the previous
approach was that `ObjCTypeParamType::desugar` was returning underlying
type for `ObjCTypeParamDecl` without applying any protocols stored in
`ObjCTypeParamType`. It caused inconsistencies in comparing types before
and after desugaring.

Re-applying after fixing intermittent test failures.

rdar://problem/54329242

Reviewed By: erik.pilkington

Differential Revision: https://reviews.llvm.org/D72872
2020-04-24 16:32:28 -07:00
Erik Pilkington 85cca945b4 [SemaObjC] Forbid storing an unboxed integer literal in an NSNumber
This fixes a common mistake (the 3 should be @3): NSNumber *n = 3. This extends
an existing check for NSString. Also, this only errs if the initializer isn't a
null pointer constant, so NSNumber *n = 0; continues to work. rdar://47029572

Differential revision: https://reviews.llvm.org/D78066
2020-04-20 15:22:51 -04:00
Volodymyr Sapsai 8fb7cfcea9 Revert "[ObjC generics] Fix not inheriting type bounds in categories/extensions."
This reverts commit a8c8b627f2. It causes
intermittent

    Clang :: SemaObjC/parameterized_classes_subst.m

test failures on various bots.
2020-04-07 17:41:30 -07:00
Volodymyr Sapsai a8c8b627f2 [ObjC generics] Fix not inheriting type bounds in categories/extensions.
When a category/extension doesn't repeat a type bound, corresponding
type parameter is substituted with `id` when used as a type argument. As
a result, in the added test case it was causing errors like

> type argument 'T' (aka 'id') does not satisfy the bound ('id<NSCopying>') of type parameter 'T'

We are already checking that type parameters should be consistent
everywhere (see `checkTypeParamListConsistency`) and update
`ObjCTypeParamDecl` to have correct underlying type. And when we use the
type parameter as a method return type or a method parameter type, it is
substituted to the bounded type. But when we use the type parameter as a
type argument, we check `ObjCTypeParamType` that wasn't updated and
remains `id`.

Fix by updating not only `ObjCTypeParamDecl` UnderlyingType but also
TypeForDecl as we use the underlying type to create a canonical type for
`ObjCTypeParamType` (see `ASTContext::getObjCTypeParamType`).

This is a different approach to fixing the issue. The previous one was
02c2ab3d88 which was reverted in
4c539e8da1. The problem with the previous
approach was that `ObjCTypeParamType::desugar` was returning underlying
type for `ObjCTypeParamDecl` without applying any protocols stored in
`ObjCTypeParamType`. It caused inconsistencies in comparing types before
and after desugaring.

rdar://problem/54329242

Reviewed By: erik.pilkington

Differential Revision: https://reviews.llvm.org/D72872
2020-04-03 16:29:02 -07:00
Richard Smith 0c42539df3 Improve error recovery from missing '>' in template argument list.
Produce the conventional "to match this '<'" note, so that the user
knows why we expected a '>', and properly handle '>>' in C++11 onwards.
2020-03-27 18:59:01 -07:00
Pierre Habouzit 20d704a75e [objc_direct] also go through implementations when looking for clashes
Some methods are sometimes declared in the @implementation blocks which
can cause undiagnosed clashes.

Just write a checkObjCDirectMethodClashes() for this purpose.

Also make sure that "unavailable" selectors do not inherit
objc_direct_members.

Differential Revision: https://reviews.llvm.org/D76643
Signed-off-by: Pierre Habouzit <phabouzit@apple.com>
Radar-ID: rdar://problem/59332804, rdar://problem/59782963
2020-03-23 20:49:09 -07:00
Akira Hatanaka 40568fec7e [CodeGen] Emit destructor calls to destruct compound literals
Fix a bug in IRGen where it wasn't destructing compound literals in C
that are ObjC pointer arrays or non-trivial structs. Also diagnose jumps
that enter or exit the lifetime of the compound literals.

rdar://problem/51867864

Differential Revision: https://reviews.llvm.org/D64464
2020-03-10 14:08:28 -07:00
Erik Pilkington e392dcd570 [Sema] Look through OpaqueValueExpr when checking implicit conversions
Specifically, this fixes a false-positive in -Wobjc-signed-char-bool.
rdar://57372317

Differential revision: https://reviews.llvm.org/D75387
2020-03-02 11:24:36 -08:00
Erik Pilkington 2e4f5e629d [Sema] Fix an assert when objc_externally_retained was applied to an unprototyped function
rdar://58893199
2020-02-28 15:49:16 -08:00
Anastasia Stulova fa755d3e71 [Sema][C++] Propagate conversion kind to specialize the diagnostics
Compute and propagate conversion kind to diagnostics helper in C++
to provide more specific diagnostics about incorrect implicit
conversions in assignments, initializations, params, etc...

Duplicated some diagnostics as errors because C++ is more strict.

Tags: #clang

Differential Revision: https://reviews.llvm.org/D74116
2020-02-25 16:05:37 +00:00
Pierre Habouzit 3adcc78a80 [objc_direct] Small updates to help with adoption.
Add fixits for messaging self in MRR or using super, as the intent is
clear, and it turns out people do that a lot more than expected.

Allow for objc_direct_members on main interfaces, it's extremely useful
for internal only classes, and proves to be quite annoying for adoption.

Add some better warnings around properties direct/non-direct clashes (it
was done for methods but properties were a miss).

Add some errors when direct properties are marked @dynamic.

Radar-Id: rdar://problem/58355212
Signed-off-by: Pierre Habouzit <phabouzit@apple.com>
Differential Revision: https://reviews.llvm.org/D73755
2020-02-16 16:32:41 -08:00
Mark de Wever 9658d895c8 [Sema] Adds the pointer-to-int-cast diagnostic
Converting a pointer to an integer whose result cannot represented in the
integer type is undefined behavior is C and prohibited in C++. C++ already
has a diagnostic when casting. This adds a diagnostic for C.

Since this diagnostic uses the range of the conversion it also modifies
int-to-pointer-cast diagnostic to use a range.

Fixes PR8718: No warning on casting between pointer and non-pointer-sized int

Differential Revision: https://reviews.llvm.org/D72231
2020-02-16 15:38:25 +01:00
Pierre Habouzit c6cf3602e2 Revert "[objc_direct] Small updates to help with adoption."
This reverts commit bebb8e2596.

Pushed by accident, not yet reviewed
2020-01-30 18:21:25 -08:00
Pierre Habouzit bebb8e2596 [objc_direct] Small updates to help with adoption.
Add fixits for messaging self in MRR or using super, as the intent is
clear, and it turns out people do that a lot more than expected.

Allow for objc_direct_members on main interfaces, it's extremely useful
for internal only classes, and proves to be quite annoying for adoption.

Add some better warnings around properties direct/non-direct clashes (it
was done for methods but properties were a miss).

Radar-Id: rdar://problem/58355212
Signed-off-by: Pierre Habouzit <phabouzit@apple.com>
2020-01-30 18:17:45 -08:00
Pierre Habouzit 7596d3c50c [objc_direct] Allow for direct messages be sent to `self` when it is a Class
Sending a message to `self` when it is const and within a class method
is safe because we know that `self` is the Class itself.

We can only relax this warning in ARC.

Signed-off-by: Pierre Habouzit <phabouzit@apple.com>
Radar-Id: rdar://problem/58581965
Differential Revision: https://reviews.llvm.org/D72747
2020-01-23 22:39:28 -08:00
Richard Smith fbf915f01d Add a FIXME and corresponding test coverage for some suspicious behavior
forming composite ObjC pointer types in comparisons.
2020-01-10 16:12:00 -08:00
Pierre Habouzit 42f9d0c0be [objc_direct] Tigthen checks for direct methods
Because the name of a direct method must be agreed upon by the caller
and the implementation, certain bad practices that one can get away with
when using dynamism are fatal with direct methods.

To avoid really weird and unscruttable linker error, tighten the
front-end error reporting.

Rule 1:
  Direct methods can only have at most one declaration in an @interface
  container. Any redeclaration is strictly forbidden.

  Today some amount of redeclaration is tolerated between the main
  interface and categories for dynamic methods, but we can't have that.

Rule 2:
  Direct method implementations can only be declared in a matching
  @interface container: when implemented in the primary @implementation
  then the declaration must be in the primary @interface or an
  extension, and when implemented in a category, the declaration must be
  in the @interface for the same category.

Also fix another issue with ObjCMethod::getCanonicalDecl(): when an
implementation lives in the primary @interface, then its canonical
declaration can be in any extension, even when it's not an accessor.

Add Sema tests to cover the new errors, and CG tests to beef up testing
around function names for categories and extensions.

Radar-Id: <rdar://problem/58054563>

Differential Revision: https://reviews.llvm.org/D71694
2019-12-20 10:57:36 -08:00
Adrian Prantl a1a9aa17b4 Set a source location for Objective-C accessor stubs
even when there is no explicit synthesize statement.

This fixes a regression introduced in https://reviews.llvm.org/D68108
that could lead to missing debug locations in cleanup code in
synthesized Objective-C++ properties.

rdar://57630879

Differential Revision: https://reviews.llvm.org/D71084
2019-12-05 12:45:10 -08:00
Erik Pilkington 8bfb353bb3 [Sema] Fix a -Wobjc-signed-char-bool false-positive
Unsigned bit-field flags can only have boolean values, so handle that case in
Expr::isKnownToHaveBooleanValue.

rdar://56256999
2019-11-18 12:15:20 -08:00
Pierre Habouzit d4e1ba3fa9 Implement __attribute__((objc_direct)), __attribute__((objc_direct_members))
__attribute__((objc_direct)) is an attribute on methods declaration, and
__attribute__((objc_direct_members)) on implementation, categories or
extensions.

A `direct` property specifier is added (@property(direct) type name)

These attributes / specifiers cause the method to have no associated
Objective-C metadata (for the property or the method itself), and the
calling convention to be a direct C function call.

The symbol for the method has enforced hidden visibility and such direct
calls are hence unreachable cross image. An explicit C function must be
made if so desired to wrap them.

The implicit `self` and `_cmd` arguments are preserved, however to
maintain compatibility with the usual `objc_msgSend` semantics,
3 fundamental precautions are taken:

1) for instance methods, `self` is nil-checked. On arm64 backends this
   typically adds a single instruction (cbz x0, <closest-ret>) to the
   codegen, for the vast majority of the cases when the return type is a
   scalar.

2) for class methods, because the class may not be realized/initialized
   yet, a call to `[self self]` is emitted. When the proper deployment
   target is used, this is optimized to `objc_opt_self(self)`.

   However, long term we might want to emit something better that the
   optimizer can reason about. When inlining kicks in, these calls
   aren't optimized away as the optimizer has no idea that a single call
   is really necessary.

3) the calling convention for the `_cmd` argument is changed: the caller
   leaves the second argument to the call undefined, and the selector is
   loaded inside the body when it's referenced only.

As far as error reporting goes, the compiler refuses:
- making any overloads direct,
- making an overload of a direct method,
- implementations marked as direct when the declaration in the
  interface isn't (the other way around is allowed, as the direct
  attribute is inherited from the declaration),
- marking methods required for protocol conformance as direct,
- messaging an unqualified `id` with a direct method,
- forming any @selector() expression with only direct selectors.

As warnings:
- any inconsistency of direct-related calling convention when
  @selector() or messaging is used,
- forming any @selector() expression with a possibly direct selector.

Lastly an `objc_direct_members` attribute is added that can decorate
`@implementation` blocks and causes methods only declared there (and in
no `@interface`) to be automatically direct. When decorating an
`@interface` then all methods and properties declared in this block are
marked direct.

Radar-ID: rdar://problem/2684889
Differential Revision: https://reviews.llvm.org/D69991
Reviewed-By: John McCall
2019-11-18 11:48:40 -08:00
Adrian Prantl 9e48a946b7 Fix two typos in one test name, three days before its 10th birthday! (NFC) 2019-11-08 09:03:46 -08:00
Adrian Prantl 2073dd2da7 Redeclare Objective-C property accessors inside the ObjCImplDecl in which they are synthesized.
This patch is motivated by (and factored out from)
https://reviews.llvm.org/D66121 which is a debug info bugfix. Starting
with DWARF 5 all Objective-C methods are nested inside their
containing type, and that patch implements this for synthesized
Objective-C properties.

1. SemaObjCProperty populates a list of synthesized accessors that may
   need to inserted into an ObjCImplDecl.

2. SemaDeclObjC::ActOnEnd inserts forward-declarations for all
   accessors for which no override was provided into their
   ObjCImplDecl. This patch does *not* synthesize AST function
   *bodies*. Moving that code from the static analyzer into Sema may
   be a good idea though.

3. Places that expect all methods to have bodies have been updated.

I did not update the static analyzer's inliner for synthesized
properties to point back to the property declaration (see
test/Analysis/Inputs/expected-plists/nullability-notes.m.plist), which
I believed to be more bug than a feature.

Differential Revision: https://reviews.llvm.org/D68108

rdar://problem/53782400
2019-11-08 08:23:22 -08:00
Hans Wennborg 4c539e8da1 Revert r374202"[ObjC generics] Fix not inheriting type bounds in categories/extensions."
This introduced new errors, see below. Reverting until that can be investigated
properly.

  #import <AVFoundation/AVFoundation.h>

  void f(int width, int height) {
    FourCharCode best_fourcc = kCMPixelFormat_422YpCbCr8_yuvs;
    NSDictionary* videoSettingsDictionary = @{
      (id)kCVPixelBufferPixelFormatTypeKey : @(best_fourcc),
    };
  }

  $ clang++ -c /tmp/a.mm

  /tmp/a.mm:6:5: error: cannot initialize a parameter of type
  'KeyType<NSCopying>  _Nonnull const' (aka 'const id') with an rvalue
  of type 'id'
      (id)kCVPixelBufferPixelFormatTypeKey : @(best_fourcc),
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  1 error generated.

> When a category/extension doesn't repeat a type bound, corresponding
> type parameter is substituted with `id` when used as a type argument. As
> a result, in the added test case it was causing errors like
>
> > type argument 'T' (aka 'id') does not satisfy the bound ('id<NSCopying>') of type parameter 'T'
>
> We are already checking that type parameters should be consistent
> everywhere (see `checkTypeParamListConsistency`) and update
> `ObjCTypeParamDecl` to have correct underlying type. And when we use the
> type parameter as a method return type or a method parameter type, it is
> substituted to the bounded type. But when we use the type parameter as a
> type argument, we check `ObjCTypeParamType` that ignores the updated
> underlying type and remains `id`.
>
> Fix by desugaring `ObjCTypeParamType` to the underlying type, the same
> way we are doing with `TypedefType`.
>
> rdar://problem/54329242
>
> Reviewers: erik.pilkington, ahatanak
>
> Reviewed By: erik.pilkington
>
> Subscribers: jkorous, dexonsmith, ributzka, cfe-commits
>
> Differential Revision: https://reviews.llvm.org/D66696
2019-10-22 22:39:01 +02:00
James Y Knight ccc4d83cda [ObjC] Diagnose implicit type coercion from ObjC 'Class' to object
pointer types.

For example, in Objective-C mode, the initialization of 'x' in:
```
  @implementation MyType
  + (void)someClassMethod {
    MyType *x = self;
  }
  @end
```
is correctly diagnosed with an incompatible-pointer-types warning, but
in Objective-C++ mode, it is not diagnosed at all -- even though
incompatible pointer conversions generally become an error in C++.

This patch fixes that oversight, allowing implicit conversions
involving Class only to/from unqualified-id, and between qualified and
unqualified Class, where the protocols are compatible.

Note that this does change some behaviors in Objective-C, as well, as
shown by the modified tests.

Of particular note is that assignment from from 'Class<MyProtocol>' to
'id<MyProtocol>' now warns. (Despite appearances, those are not
compatible types. 'Class<MyProtocol>' is not expected to have instance
methods defined by 'MyProtocol', while 'id<MyProtocol>' is.)

Differential Revision: https://reviews.llvm.org/D67983

llvm-svn: 375125
2019-10-17 15:27:04 +00:00
James Y Knight 1c982af059 [ObjC] Add some additional test cases around pointer conversions.
This is especially important for Objective-C++, which is entirely
missing this testing at the moment.

This annotates with "FIXME" the cases which I change in the next
patch -- I primarily wanted to document the current state of things so
that the effect of the code change is made clear.

Differential Revision: https://reviews.llvm.org/D67982

llvm-svn: 375124
2019-10-17 15:18:59 +00:00
Volodymyr Sapsai 02c2ab3d88 [ObjC generics] Fix not inheriting type bounds in categories/extensions.
When a category/extension doesn't repeat a type bound, corresponding
type parameter is substituted with `id` when used as a type argument. As
a result, in the added test case it was causing errors like

> type argument 'T' (aka 'id') does not satisfy the bound ('id<NSCopying>') of type parameter 'T'

We are already checking that type parameters should be consistent
everywhere (see `checkTypeParamListConsistency`) and update
`ObjCTypeParamDecl` to have correct underlying type. And when we use the
type parameter as a method return type or a method parameter type, it is
substituted to the bounded type. But when we use the type parameter as a
type argument, we check `ObjCTypeParamType` that ignores the updated
underlying type and remains `id`.

Fix by desugaring `ObjCTypeParamType` to the underlying type, the same
way we are doing with `TypedefType`.

rdar://problem/54329242

Reviewers: erik.pilkington, ahatanak

Reviewed By: erik.pilkington

Subscribers: jkorous, dexonsmith, ributzka, cfe-commits

Differential Revision: https://reviews.llvm.org/D66696

llvm-svn: 374202
2019-10-09 19:29:13 +00:00
Ilya Biryukov aeae71cd96 [Sema] Emit diagnostics for uncorrected delayed typos at the end of TU
Summary:
Instead of asserting all typos are corrected in the sema destructor.

The sema destructor is not run in the common case of running the compiler
with the -disable-free cc1 flag (which is the default in the driver).

Having this assertion led to crashes in libclang and clangd, which are not
reproducible when running the compiler.

Asserting at the end of the TU could be an option, but finding all
missing typo correction cases is hard and having worse diagnostics instead
of a failing assertion is a better trade-off.

For more discussion on this, see:
https://lists.llvm.org/pipermail/cfe-dev/2019-July/062872.html

Reviewers: sammccall, rsmith

Reviewed By: rsmith

Subscribers: usaxena95, dgoldman, jkorous, vsapsai, rnk, kadircet, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D64799

llvm-svn: 374152
2019-10-09 10:00:05 +00:00
Erik Pilkington 5c62152275 [Sema] Split of versions of -Wimplicit-{float,int}-conversion for Objective-C BOOL
Also, add a diagnostic group, -Wobjc-signed-char-bool, to control all these
related diagnostics.

rdar://51954400

Differential revision: https://reviews.llvm.org/D67559

llvm-svn: 372183
2019-09-17 21:11:51 +00:00
Akira Hatanaka 3f2c9917a4 [Sema][ObjC] Mark C union fields that have non-trivial ObjC ownership
qualifications as unavailable if the union is declared in a system
header

r365985 stopped marking those fields as unavailable, which caused the
union's NonTrivialToPrimitive* bits to be set to true. This patch
restores the behavior prior to r365985, except that users can explicitly
specify the ownership qualification of the field to instruct the
compiler not to mark it as unavailable.

rdar://problem/53420753

Differential Revision: https://reviews.llvm.org/D65256

llvm-svn: 371276
2019-09-07 00:34:47 +00:00
Akira Hatanaka 090510608d [Sema] Diagnose default-initialization, destruction, and copying of
non-trivial C union types

This recommits r365985, which was reverted because it broke a few
projects using unions containing non-trivial ObjC pointer fields in
system headers. We now have a patch to fix the problem (see
https://reviews.llvm.org/D65256).

Original commit message:

This patch diagnoses uses of non-trivial C unions and structs/unions
containing non-trivial C unions in the following contexts, which require
default-initialization, destruction, or copying of the union objects,
instead of disallowing fields of non-trivial types in C unions, which is
what we currently do:

- function parameters.
- function returns.
- assignments.
- compound literals.
- block captures except capturing of `__block` variables by non-escaping blocks.
- local and global variable definitions.
- lvalue-to-rvalue conversions of volatile types.

See the discussion in https://reviews.llvm.org/D62988 for more background.

rdar://problem/50679094

Differential Revision: https://reviews.llvm.org/D63753

llvm-svn: 371275
2019-09-07 00:34:43 +00:00
Volodymyr Sapsai 73152a2ec2 [ObjC] Fix type checking for qualified id block parameters.
When checking if block types are compatible, we are checking for
compatibility their return types and parameters' types. As these types
have different variance, we need to check them in different order.

rdar://problem/52788423

Reviewers: erik.pilkington, arphaman

Reviewed By: arphaman

Subscribers: jkorous, dexonsmith, ributzka, cfe-commits

Differential Revision: https://reviews.llvm.org/D66831

llvm-svn: 370130
2019-08-28 00:25:06 +00:00
Erik Pilkington aa3855694f [Sema][ObjC] Fix a -Wformat false positive with localizedStringForKey
Only honour format_arg attributes on -[NSBundle localizedStringForKey] when its
argument has a format specifier in it, otherwise its likely to just be a key to
fetch localized strings.

Fixes rdar://23622446

Differential revision: https://reviews.llvm.org/D27165

llvm-svn: 368878
2019-08-14 16:57:11 +00:00
Richard Sandiford eb485fbc71 Add SVE opaque built-in types
This patch adds the SVE built-in types defined by the Procedure Call
Standard for the Arm Architecture:

   https://developer.arm.com/docs/100986/0000

It handles the types in all relevant places that deal with built-in types.
At the moment, some of these places bail out with an error, including:

   (1) trying to generate LLVM IR for the types
   (2) trying to generate debug info for the types
   (3) trying to mangle the types using the Microsoft C++ ABI
   (4) trying to @encode the types in Objective C

(1) and (2) are fixed by follow-on patches but (unlike this patch)
they deal mostly with target-specific LLVM details, so seemed like
a logically separate change.  There is currently no spec for (3) and
(4), so reporting an error seems like the correct behaviour for now.

The intention is that the types will become sizeless types:

   http://lists.llvm.org/pipermail/cfe-dev/2019-June/062523.html

The main purpose of the sizeless type extension is to diagnose
impossible or dangerous uses of the types, such as any that would
require sizeof to have a meaningful defined value.

Until then, the patch sets the alignments of the types to the values
specified in the link above.  It also sets the sizes of the types to
zero, which is chosen to be consistently wrong and shouldn't affect
correctly-written code (i.e. code that would compile even with the
sizeless type extension).

The patch adds the common subset of functionality needed to test the
sizeless type extension on the one hand and to provide SVE intrinsic
functions on the other.  After this patch, the two pieces of work are
essentially independent.

The patch is based on one by Graham Hunter:

   https://reviews.llvm.org/D59245

Differential Revision: https://reviews.llvm.org/D62960

llvm-svn: 368413
2019-08-09 08:52:54 +00:00
Akira Hatanaka 6f6156b9fc Revert "[Sema] Diagnose default-initialization, destruction, and copying of"
This reverts commit r365985.

Prior to r365985, clang used to mark C union fields that have
non-trivial ObjC ownership qualifiers as unavailable if the union was
declared in a system header. r365985 stopped doing so, which caused the
swift compiler to crash when it tried to import a non-trivial union.

I have a patch that fixes the crash (https://reviews.llvm.org/D65256),
but I'm temporarily reverting the original patch until we can decide on
whether it's taking the right approach.

llvm-svn: 367076
2019-07-26 00:02:17 +00:00
Akira Hatanaka 81b03d4a08 [Sema] Diagnose default-initialization, destruction, and copying of
non-trivial C union types

This patch diagnoses uses of non-trivial C unions and structs/unions
containing non-trivial C unions in the following contexts, which require
default-initialization, destruction, or copying of the union objects,
instead of disallowing fields of non-trivial types in C unions, which is
what we currently do:

- function parameters.
- function returns.
- assignments.
- compound literals.
- block captures except capturing of `__block` variables by non-escaping
  blocks.
- local and global variable definitions.
- lvalue-to-rvalue conversions of volatile types.

See the discussion in https://reviews.llvm.org/D62988 for more background.

rdar://problem/50679094

Differential Revision: https://reviews.llvm.org/D63753

llvm-svn: 365985
2019-07-13 01:47:15 +00:00
Reid Kleckner 345708b681 Revert [Sema] Resolve placeholder types before type deduction to silence spurious `-Warc-repeated-use-of-weak` warnings
This reverts r365382 (git commit 8b1becf2e3)

Appears to regress this semi-reduced fragment of valid code from windows
SDK headers:

  #define InterlockedIncrement64 _InterlockedIncrement64
  extern "C" __int64 InterlockedIncrement64(__int64 volatile *Addend);
  #pragma intrinsic(_InterlockedIncrement64)
  unsigned __int64 InterlockedIncrement(unsigned __int64 volatile *Addend) {
    return (unsigned __int64)(InterlockedIncrement64)((volatile __int64 *)Addend);
  }

Found on a buildbot here, but no mail was sent due to it already being
red:
http://lab.llvm.org:8011/builders/sanitizer-windows/builds/48067

llvm-svn: 365393
2019-07-08 21:59:07 +00:00
Akira Hatanaka 8b1becf2e3 [Sema] Resolve placeholder types before type deduction to silence
spurious `-Warc-repeated-use-of-weak` warnings

The spurious -Warc-repeated-use-of-weak warnings are issued when an
initializer expression uses a weak ObjC pointer.

My first attempt to silence the warnings (r350917) caused clang to
reject code that is legal in C++17. The patch is based on the feedback I
received from Richard when the patch was reverted.

http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20190422/268945.html
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20190422/268943.html

Differential Revision: https://reviews.llvm.org/D62645

llvm-svn: 365382
2019-07-08 20:04:39 +00:00
Erik Pilkington d7999cbc6e [ObjC] Improve error message for a malformed objc-type-name
If the type didn't exist, we used to emit a really bad error:

t.m:3:12: error: expected ')'
-(nullable NoSuchType)foo3;
           ^

rdar://50925632

llvm-svn: 364489
2019-06-26 23:39:23 +00:00
John McCall 2c91c3b7af Add the `objc_class_stub` attribute.
Swift requires certain classes to be not just initialized lazily on first
use, but actually allocated lazily using information that is only available
at runtime.  This is incompatible with ObjC class initialization, or at least
not efficiently compatible, because there is no meaningful class symbol
that can be put in a class-ref variable at load time.  This leaves ObjC
code unable to access such classes, which is undesirable.

objc_class_stub says that class references should be resolved by calling
a new ObjC runtime function with a pointer to a new "class stub" structure.
Non-ObjC compilers (like Swift) can simply emit this structure when ObjC
interop is required for a class that cannot be statically allocated,
then apply this attribute to the `@interface` in the generated ObjC header
for the class.

This attribute can be thought of as a generalization of the existing
`objc_runtime_visible` attribute which permits more efficient class
resolution as well as supporting the additon of categories to the class.
Subclassing these classes from ObjC is currently not allowed.

Patch by Slava Pestov!

llvm-svn: 362054
2019-05-30 04:09:01 +00:00
Leonard Chan 3af7cf58bb Remove unicode character from test
llvm-svn: 361302
2019-05-21 20:12:00 +00:00
Leonard Chan 16beaae2a6 [Sema] Fix for build on some iOS programs.
Nullability attributes weren't being stripped for AttributedTypes that
were wrapped in a MacroQualifiedType. This fix adds a check for this
type and a test.

llvm-svn: 361205
2019-05-20 22:42:19 +00:00
Leonard Chan aae9da70ff Fix for the greendragon bots.
Adds extra checks for ObjC GC and Ownership.

llvm-svn: 360225
2019-05-08 05:59:25 +00:00
Leonard Chan c72aaf62d3 Recommit r359859 "[Attribute/Diagnostics] Print macro if definition is an attribute declaration"
Updated with fix for read of uninitialized memory.

llvm-svn: 360109
2019-05-07 03:20:17 +00:00
Akira Hatanaka 8cd01e69d8 [Sema][ObjC] Disable -Wunused-parameter for ObjC methods
The warning isn't very useful when the function is an ObjC method.

rdar://problem/41561853

Differential Revision: https://reviews.llvm.org/D61147

llvm-svn: 359864
2019-05-03 07:19:46 +00:00
Leonard Chan ef2dc25a96 Revert "[Attribute/Diagnostics] Print macro if definition is an attribute declaration"
This reverts commit fc40cbd9d8.

llvm-svn: 359859
2019-05-03 03:28:06 +00:00
Leonard Chan fc40cbd9d8 [Attribute/Diagnostics] Print macro if definition is an attribute declaration
If an address_space attribute is defined in a macro, print the macro instead
when diagnosing a warning or error for incompatible pointers with different
address_spaces.

We allow this for all attributes (not just address_space), and for multiple
attributes declared in the same macro.

Differential Revision: https://reviews.llvm.org/D51329

llvm-svn: 359826
2019-05-02 20:38:14 +00:00
Volodymyr Sapsai 31f7c4aa77 [Parser] Avoid correcting delayed typos in array subscript multiple times.
We correct some typos in `ActOnArraySubscriptExpr` and
`ActOnOMPArraySectionExpr`, so when their result is `ExprError`, we can
end up correcting delayed typos in the same expressions again. In
general it is OK but when `NumTypos` is incorrect, we can hit the
assertion

> Assertion failed: (Entry != DelayedTypos.end() && "Failed to get the state for a TypoExpr!"), function getTypoExprState, file clang/lib/Sema/SemaLookup.cpp, line 5219.

Fix by replacing some subscript `ExprResult` with typo-corrected expressions
instead of keeping the original expressions. Thus if original expressions
contained `TypoExpr`, we'll use corrected expressions instead of trying to
correct them again.

rdar://problem/47403222

Reviewers: rsmith, erik.pilkington, majnemer

Reviewed By: erik.pilkington

Subscribers: jkorous, dexonsmith, cfe-commits

Differential Revision: https://reviews.llvm.org/D60848

llvm-svn: 359713
2019-05-01 19:24:50 +00:00
Richard Smith 42a22370f2 Revert r350917 "[Sema] If CheckPlaceholderExpr rewrites the initializer
of an auto"

This commit changed the initializer expression passed into
initialization (stripping off an enclosing pair of parentheses or
braces) and subtly changing the meaning of programs, typically by
inserting bogus calls to copy constructors.

See the added testcase in test/SemaCXX/cxx1y-init-captures.cpp for an
example of the breakage.

llvm-svn: 359066
2019-04-24 02:22:38 +00:00
Akira Hatanaka ac57af3284 [Sema][ObjC] Don't warn about an implicitly retained self if the
retaining block and all of the enclosing blocks are non-escaping.

If the block implicitly retaining self doesn't escape, there is no risk
of creating retain cycles, so clang shouldn't diagnose it and force
users to add self-> to silence the diagnostic.

Also, fix a bug where clang was failing to diagnose an implicitly
retained self inside a c++ lambda nested inside a block.

rdar://problem/25059955

Differential Revision: https://reviews.llvm.org/D60736

llvm-svn: 358624
2019-04-17 23:14:44 +00:00
Erik Pilkington 1138d8c892 Support objc_nonlazy_class attribute on Objective-C implementations
Fixes rdar://49523079

Differential revision: https://reviews.llvm.org/D60544

llvm-svn: 358201
2019-04-11 17:55:34 +00:00