Commit Graph

403 Commits

Author SHA1 Message Date
Jordan Rose 06dd406e27 Add fix-it notes to the nullability consistency warning.
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
2016-12-19 20:58:20 +00:00
Alex Lorenz e151f010de [ObjC++] Don't enter a C++ declarator scope when the current context is
an Objective-C declaration

This commit ensures that Sema won't enter a C++ declarator scope when the
current context is an Objective-C declaration. This prevents an assertion
failure in EnterDeclaratorContext that's used to ensure that current context
will be restored correctly after exiting the declarator context.

rdar://20560175

Differential Revision: https://reviews.llvm.org/D26922

llvm-svn: 288893
2016-12-07 10:24:44 +00:00
Jordan Rose 16d52a2a72 Don't require nullability on 'va_list'.
There are many non-portable typedefs, but va_list is one that nobody
ever thinks of as a pointer or an array. (When's the last time you saw
someone check for a NULL va_list?) Make an exception for this one
special type.

Part of rdar://problem/25846421.

llvm-svn: 286522
2016-11-10 23:28:34 +00:00
Jordan Rose 3b917fe019 Warn when 'assume_nonnull' infers nullability within an array.
...or within a reference. Both of these add an extra level of
indirection that make us less certain that the pointer really was
supposed to be non-nullable. However, changing the default behavior
would be a breaking change, so we'll just make it a warning instead.

Part of rdar://problem/25846421

llvm-svn: 286521
2016-11-10 23:28:30 +00:00
Jordan Rose f85a9b06b8 Add -Wnullability-completeness-on-arrays.
This is an addition to (and sub-warning of) -Wnullability-completeness
that warns when an array parameter is missing nullability. When the
specific warning is switched off, the compiler falls back to only
warning on pointer types written as pointer types.

Note that use of nullability /within/ an array triggers the
completeness checks regardless of whether or not the array-specific
warning is enabled; the intent there is simply to determine whether a
particular header is trying to be nullability-aware at all.

Part of rdar://problem/25846421.

llvm-svn: 286520
2016-11-10 23:28:26 +00:00
Jordan Rose ce65364afc Don't require nullability on template parameters in typedefs.
Previously the following code would warn on the use of "T":

  template <typename T>
  struct X {
    typedef T *type;
  };

...because nullability is /allowed/ on template parameters (because
they could be pointers). (Actually putting nullability on this use of
'T' will of course break if the argument is a non-pointer type.)

This fix doesn't handle the case where a template parameter is used
/outside/ of a typedef. That seems trickier, especially in parameter
position.

llvm-svn: 285856
2016-11-02 20:44:07 +00:00
Richard Smith 5e9746f520 DR583, DR1512: Implement a rewrite to C++'s 'composite pointer type' rules.
This has two significant effects:

1) Direct relational comparisons between null pointer constants (0 and nullopt)
   and pointers are now ill-formed. This was always the case for C, and it
   appears that C++ only ever permitted by accident. For instance, cases like
     nullptr < &a
   are now rejected.

2) Comparisons and conditional operators between differently-cv-qualified
   pointer types now work, and produce a composite type that both source
   pointer types can convert to (when possible). For instance, comparison
   between 'int **' and 'const int **' is now valid, and uses an intermediate
   type of 'const int *const *'.

Clang previously supported #2 as an extension.

We do not accept the cases in #1 as an extension. I've tested a fair amount of
code to check that this doesn't break it, but if it turns out that someone is
relying on this, we can easily add it back as an extension.

This is a re-commit of r284800.

llvm-svn: 284890
2016-10-21 22:00:42 +00:00
Renato Golin 41189656ed Revert "DR583, DR1512: Implement a rewrite to C++'s 'composite pointer type' rules."
This reverts commit r284800, as it failed all ARM/AArch64 bots.

llvm-svn: 284811
2016-10-21 08:03:49 +00:00
Richard Smith 0c1c53e3fa DR583, DR1512: Implement a rewrite to C++'s 'composite pointer type' rules.
This has two significant effects:

1) Direct relational comparisons between null pointer constants (0 and nullopt)
   and pointers are now ill-formed. This was always the case for C, and it
   appears that C++ only ever permitted by accident. For instance, cases like
     nullptr < &a
   are now rejected.

2) Comparisons and conditional operators between differently-cv-qualified
   pointer types now work, and produce a composite type that both source
   pointer types can convert to (when possible). For instance, comparison
   between 'int **' and 'const int **' is now valid, and uses an intermediate
   type of 'const int *const *'.

Clang previously supported #2 as an extension.

We do not accept the cases in #1 as an extension. I've tested a fair amount of
code to check that this doesn't break it, but if it turns out that someone is
relying on this, we can easily add it back as an extension.

llvm-svn: 284800
2016-10-21 02:36:37 +00:00
Saleem Abdulrasool 511f2e5a89 Sema: support __declspec(dll*) on ObjC interfaces
Extend the __declspec(dll*) attribute to cover ObjC interfaces.  This was
requested by Microsoft for their ObjC support.  Cover both import and export.
This only adds the semantic analysis portion of the support, code-generation
still remains outstanding.  Add some basic initial documentation on the
attributes that were previously empty.  Tweak the previous tests to use the
relative expected-warnings to make the tests easier to read.

llvm-svn: 275610
2016-07-15 20:41:10 +00:00
Richard Smith 03a4aa3d00 Re-commit r273548, reverted in r273589, with a fix to not produce
-Wfor-loop-analysis warnings for a for-loop with a condition variable. In such
a case, the loop condition variable is modified on each iteration of the loop
by definition.

Original commit message:

Rearrange condition handling so that semantic checks on a condition variable
are performed before the other substatements of the construct are parsed,
rather than deferring them until the end. This allows better error recovery
from semantic errors in the condition, improves diagnostic order, and is a
prerequisite for C++17 constexpr if.

llvm-svn: 273600
2016-06-23 19:02:52 +00:00
Peter Collingbourne b77ebd749a Revert r273548, "Rearrange condition handling so that semantic checks on a condition variable"
as it caused a regression in -Wfor-loop-analysis.

llvm-svn: 273589
2016-06-23 18:11:15 +00:00
Richard Smith 19f877c3f2 Rearrange condition handling so that semantic checks on a condition variable
are performed before the other substatements of the construct are parsed,
rather than deferring them until the end. This allows better error recovery
from semantic errors in the condition, improves diagnostic order, and is a
prerequisite for C++17 constexpr if.

llvm-svn: 273548
2016-06-23 08:41:20 +00:00
Hans Wennborg 7c09cc67aa Obj-C: Fix assert-on-invalid (PR27822)
Clang would assert when isObjCInstancetype() was called on a
tok::annot_cxxscope token.

llvm-svn: 271688
2016-06-03 16:59:13 +00:00
Akira Hatanaka c482acd2e5 [ObjC] Enter a new evaluation context before calling
BuildBlockForLambdaConversion.

Previously, clang would build an incorrect AST for the following code:

id test() {
  return @{@"a": [](){}, @"b": [](){}};
}

ReturnStmt 0x10d080448
`-ExprWithCleanups 0x10d080428
  |-cleanup Block 0x10d0801f0 // points to the second BlockDecl
    ...
    -BlockDecl 0x10d07f150 // First block
    ...
    -BlockDecl 0x10d0801f0 // Second block
    ...
     `-ExprWithCleanups 0x10d0801d0
       |-cleanup Block 0x10d07f150 // points to the first BlockDecl

To fix the bug, this commit enters a new evaluation context to reset
ExprNeedsCleanups before each block is parsed.

rdar://problem/16879958

Differential Revision: http://reviews.llvm.org/D18815

llvm-svn: 268527
2016-05-04 18:07:20 +00:00
Manman Ren 1c40052646 [ObjCXX] Warn undeclared identifiers.
Instantiation dependence were not being handled correctly for OpqaueValueExpr
AST nodes. As a result, if an undeclared identifier was used in a CXXNewExpr
that is assigned to a ObjC property, there would be no error during parsing, and
there would be a crash during code gen. This patch makes sure that an error
will be issued during parsing in this case.

Before the fix, if CXXNewExpr has a typo, its InstantiationDependent will be
set to true, but if it is wrapped in a OpaqueValueExpr, the OpaqueValueExpr will
not be instantiation dependent, causing the TypoExpr not be to resolved. The fix
propagates InstantiationDependent to OpaqueValueExpr from its SourceExpr. It
also propagates the other instantiation bits.

rdar://24975562

Differential Revision: http://reviews.llvm.org/D18461

llvm-svn: 264444
2016-03-25 18:43:46 +00:00
John McCall 3b5a8f5ffc Improve some infrastructure for extended parameter infos and
fix a bug with the instantiation of ns_consumed parameter
attributes in ARC.

llvm-svn: 262551
2016-03-03 00:10:03 +00:00
John McCall 62969a39fa Test template instantiation of ns_consumed and ns_returns_retained.
llvm-svn: 262311
2016-03-01 06:54:30 +00:00
Akira Hatanaka be8f522ef3 [Sema] Remove assert in TreeTransform<Derived>::TransformObjCObjectType.
The assert isn't correct since TypeLoc::ObjCObjectTypeLoc doesn't
indicate whether the type is a dependent type. The function returns
false for a type like "<SomeProtocol>" which is a synonym for
"id<SomeProtocol>".

rdar://problem/23838912

Differential Revision: http://reviews.llvm.org/D17355

llvm-svn: 261829
2016-02-25 07:08:33 +00:00
Akira Hatanaka cb4525443c [Sema] Fix bug in TypeLocBuilder::pushImpl
The code in TypeLocBuilder::pushImpl wasn't correctly handling the case
where an element that has an 8-byte alignment was being pushed.

I plan to follow up with a patch to remove redundancies and simplify the
function.

rdar://problem/23838912

Differential Revision: http://reviews.llvm.org/D16843

llvm-svn: 261260
2016-02-18 21:05:09 +00:00
Manman Ren 8abc2e51b8 ObjCXX: fix a crash during typo correction.
For ObjCXX, we can create a CastExpr with Kind being CK_UserDefinedConversion
and SubExpr being BlockExpr. Specifically one can return BlockExpr from
BuildCXXMemberCallExpr and the result can be used to build a CastExpr.

Fix the assumption in CastExpr::getSubExprAsWritten that SubExpr can only
be CXXMemberCallExpr.

rdar://problem/24364077

llvm-svn: 259591
2016-02-02 22:23:03 +00:00
John McCall 9d145df4c8 Allow pseudo-destructor calls on forward-declared Objective-C class pointers.
rdar://18522255

llvm-svn: 255531
2015-12-14 19:12:54 +00:00
Charles Li 85dec55989 [Lit Test] Updated 20 Lit tests to be C++11 compatible.
This is the 5th Lit test patch.
Expanded expected diagnostics to vary by C++ dialect.
Expanded RUN line to: default, C++98/03 and C++11.

llvm-svn: 255196
2015-12-10 01:07:17 +00:00
Douglas Gregor 1cbb289c7d Objective-C properties: fix bogus use of "isa<>" on a QualType.
The code used "isa" to check the type and then "getAs" to look through
sugar; we need to look through the sugar when checking, too, otherwise
any kind of sugar (nullability qualifiers in the example; or a
typedef) will thwart this semantic check. Fixes rdar://problem/23804250.

llvm-svn: 255066
2015-12-08 22:45:17 +00:00
Charles Li 542f04cc4d [Lit Test] Updated 26 Lit tests to be C++11 compatible.
Expected diagnostics have been expanded to vary by C++ dialect.
RUN line has also been expanded to: default, C++98/03 and C++11.

llvm-svn: 252785
2015-11-11 19:34:47 +00:00
Douglas Gregor acf4fd3039 Stop back-patching 'readonly' Objective-C properties with 'readwrite' ones.
A 'readonly' Objective-C property declared in the primary class can
effectively be shadowed by a 'readwrite' property declared within an
extension of that class, so long as the types and attributes of the
two property declarations are compatible.

Previously, this functionality was implemented by back-patching the
original 'readonly' property to make it 'readwrite', destroying source
information and causing some hideously redundant, incorrect
code. Simplify the implementation to express how this should actually
be modeled: as a separate property declaration in the extension that
shadows (via the name lookup rules) the declaration in the primary
class. While here, correct some broken Fix-Its, eliminate a pile of
redundant code, clean up the ARC migrator's handling of properties
declared in extensions, and fix debug info's naming of methods that
come from categories.

A wonderous side effect of doing this write is that it eliminates the
"AddedObjCPropertyInClassExtension" method from the AST mutation
listener, which in turn eliminates the last place where we rewrite
entire declarations in a chained PCH file or a module file. This
change (which fixes rdar://problem/18475765) will allow us to
eliminate the rewritten-decls logic from the serialization library,
and fixes a crash (rdar://problem/23247794) illustrated by the
test/PCH/chain-categories.m example.

llvm-svn: 251874
2015-11-03 01:15:46 +00:00
John McCall c6af8c606d Refine r251469 to give better (and more localizable) diagnostics
for all the reasons that ARC makes things implicitly unavailable.

llvm-svn: 251496
2015-10-28 05:03:19 +00:00
John McCall a62c1a94c1 Add the ability to define "fake" arguments on attributes.
Fake arguments are automatically handled for serialization, cloning,
and other representational tasks, but aren't included in pretty-printing
or parsing (should we eventually ever automate that).

This is chiefly useful for attributes that can be written by the
user, but which are also frequently synthesized by the compiler,
and which we'd like to remember details of the synthesis for.
As a simple example, use this to narrow the cases in which we were
generating a specialized note for implicitly unavailable declarations.

llvm-svn: 251469
2015-10-28 00:17:34 +00:00
John McCall b61e14e596 Be more conservative about diagnosing "incorrect" uses of __weak:
allow them to be written in certain kinds of user declaration and
diagnose on the use-site instead.

Also, improve and fix some diagnostics relating to __weak and
properties.

rdar://23228631

llvm-svn: 251384
2015-10-27 04:54:50 +00:00
John McCall 039f2bbd02 Some minor ARC diagnostic improvements.
llvm-svn: 250917
2015-10-21 18:06:38 +00:00
Douglas Gregor d4f2afa23c Fix inference of _Nullable for weak Objective-C properties.
The inference of _Nullable for weak Objective-C properties was broken
in several ways:

* It was back-patching the type information very late in the process
  of checking the attributes for an Objective-C property, which is
  just wrong.
* It was using ad hoc checks to try to suppress the warning about
  missing nullability specifiers (-Wnullability-completeness), which
  didn't actual work in all cases (rdar://problem/22985457)
* It was inferring _Nullable even outside of assumes-nonnull regions,
  which is wrong.

Putting the inference of _Nullable for weak Objective-C properties in
the same place as all of the other inference logic fixes all of these
ills.

llvm-svn: 249896
2015-10-09 20:36:17 +00:00
Douglas Gregor a602a153de Perform Objective-C lifetime adjustments before comparing deduced lambda result types.
Objective-C ARC lifetime qualifiers are dropped when canonicalizing
function types. Perform the same adjustment before comparing the
deduced result types of lambdas. Fixes rdar://problem/22344904.

llvm-svn: 249065
2015-10-01 20:20:47 +00:00
John McCall 6997525eaa Forbid qualifiers on ObjC generic parameters and arguments, but
silently ignore them on arguments when they're provided indirectly
(.e.g behind a template argument or typedef).

This is mostly just good language design --- specifying that a
generic argument is __weak doesn't actually do anything --- but
it also prevents assertions when trying to apply a different
ownership qualifier.

rdar://21612439

llvm-svn: 248436
2015-09-23 22:14:21 +00:00
Nico Weber 9677562c8f Don't crash when passing &@selector to a _Nonnull parameter. Fixes PR24774.
The root cause here is that ObjCSelectorExpr is an rvalue, yet it can have its
address taken.  That's kind of awkward, but fixing this is awkward in other
ways, see https://llvm.org/bugs/show_bug.cgi?id=24774#c16 .  For now, just
fix the crash.

llvm-svn: 247740
2015-09-15 23:17:17 +00:00
Nico Weber dc8b1e5304 Move sel-address.mm from test/CodeGenCXX to test/SemaObjCXX, it's not a codegen test.
llvm-svn: 247327
2015-09-10 19:35:31 +00:00
Aaron Ballman 6924dcdf6f Add a new frontend warning for referencing members from the handler of a constructor or destructor function-try-block, which is UB in C++.
This corresponds to the CERT secure coding rule ERR53-CPP.

llvm-svn: 246548
2015-09-01 14:49:24 +00:00
Davide Italiano 32cbff7809 [Sema] Be consistent about diagnostic wording: always use "cannot".
Discussed with Richard Smith.

llvm-svn: 245162
2015-08-15 15:23:14 +00:00
Alex Denisov b7d8563973 Cleanup ObjCInterfaceDecl lookup for ObjC literals
llvm-svn: 243092
2015-07-24 05:09:40 +00:00
Alex Denisov bfa859bba4 Add missing files for objc_boxable feature.
Original patch [r240761] is missing all new files because of committer's mistake.

llvm-svn: 243018
2015-07-23 14:45:41 +00:00
David Majnemer 38a50c0a16 [Sema] Emit a better diagnostic when variable redeclarations disagree
We referred to all declaration in definitions in our diagnostic messages
which is can be inaccurate.  Instead, classify the declaration and emit
an appropriate diagnostic for the new declaration and an appropriate
note pointing to the old one.

This fixes PR24116.

llvm-svn: 242190
2015-07-14 20:08:49 +00:00
Douglas Gregor 1ac1b63c9c Implement variance for Objective-C type parameters.
Introduce co- and contra-variance for Objective-C type parameters,
which allows us to express that (for example) an NSArray is covariant
in its type parameter. This means that NSArray<NSMutableString *> * is
a subtype of NSArray<NSString *> *, which is expected of the immutable
Foundation collections.

Type parameters can be annotated with __covariant or __contravariant
to make them co- or contra-variant, respectively. This feature can be
detected by __has_feature(objc_generics_variance). Implements
rdar://problem/20217490.

llvm-svn: 241549
2015-07-07 03:58:54 +00:00
Douglas Gregor ab209d83be Implement the Objective-C __kindof type qualifier.
The __kindof type qualifier can be applied to Objective-C object
(pointer) types to indicate id-like behavior, which includes implicit
"downcasting" of __kindof types to subclasses and id-like message-send
behavior. __kindof types provide better type bounds for substitutions
into unspecified generic types, which preserves more type information.

llvm-svn: 241548
2015-07-07 03:58:42 +00:00
Douglas Gregor 9bda6cff20 C++ support for Objective-C lightweight generics.
Teach C++'s tentative parsing to handle specializations of Objective-C
class types (e.g., NSArray<NSString *>) as well as Objective-C
protocol qualifiers (id<NSCopying>) by extending type-annotation
tokens to handle this case. As part of this, remove Objective-C
protocol qualifiers from the declaration specifiers, which never
really made sense: instead, provide Sema entry points to make them
part of the type annotation token. Among other things, this properly
diagnoses bogus types such as "<NSCopying> id" which should have been
written as "id <NSCopying>".

Implements template instantiation support for, e.g., NSArray<T>*
in C++. Note that parameterized classes are not templates in the C++
sense, so that cannot (for example) be used as a template argument for
a template template parameter. Part of rdar://problem/6294649.

llvm-svn: 241545
2015-07-07 03:58:14 +00:00
Douglas Gregor e83b95641f Substitute type arguments into uses of Objective-C interface members.
When messaging a method that was defined in an Objective-C class (or
category or extension thereof) that has type parameters, substitute
the type arguments for those type parameters. Similarly, substitute
into property accesses, instance variables, and other references.

This includes general infrastructure for substituting the type
arguments associated with an ObjCObject(Pointer)Type into a type
referenced within a particular context, handling all of the
substitutions required to deal with (e.g.) inheritance involving
parameterized classes. In cases where no type arguments are available
(e.g., because we're messaging via some unspecialized type, id, etc.),
we substitute in the type bounds for the type parameters instead.

Example:

  @interface NSSet<T : id<NSCopying>> : NSObject <NSCopying>
  - (T)firstObject;
  @end

  void f(NSSet<NSString *> *stringSet, NSSet *anySet) {
    [stringSet firstObject]; // produces NSString*
    [anySet firstObject]; // produces id<NSCopying> (the bound)
  }

When substituting for the type parameters given an unspecialized
context (i.e., no specific type arguments were given), substituting
the type bounds unconditionally produces type signatures that are too
strong compared to the pre-generics signatures. Instead, use the
following rule:

  - In covariant positions, such as method return types, replace type
    parameters with “id” or “Class” (the latter only when the type
    parameter bound is “Class” or qualified class, e.g,
    “Class<NSCopying>”)
  - In other positions (e.g., parameter types), replace type
    parameters with their type bounds.
  - When a specialized Objective-C object or object pointer type
    contains a type parameter in its type arguments (e.g.,
    NSArray<T>*, but not NSArray<NSString *> *), replace the entire
    object/object pointer type with its unspecialized version (e.g.,
    NSArray *).

llvm-svn: 241543
2015-07-07 03:57:53 +00:00
Douglas Gregor e9d95f1ecc Handle Objective-C type arguments.
Objective-C type arguments can be provided in angle brackets following
an Objective-C interface type. Syntactically, this is the same
position as one would provide protocol qualifiers (e.g.,
id<NSCopying>), so parse both together and let Sema sort out the
ambiguous cases. This applies both when parsing types and when parsing
the superclass of an Objective-C class, which can now be a specialized
type (e.g., NSMutableArray<T> inherits from NSArray<T>).

Check Objective-C type arguments against the type parameters of the
corresponding class. Verify the length of the type argument list and
that each type argument satisfies the corresponding bound.

Specializations of parameterized Objective-C classes are represented
in the type system as distinct types. Both specialized types (e.g.,
NSArray<NSString *> *) and unspecialized types (NSArray *) are
represented, separately.

llvm-svn: 241542
2015-07-07 03:57:35 +00:00
Douglas Gregor cdfea9a7a7 Make __has_extension(assume_nonnull) always true.
llvm-svn: 240969
2015-06-29 17:25:49 +00:00
Douglas Gregor aea7afdc13 Replace __double_underscored type nullability qualifiers with _Uppercase_underscored
Addresses a conflict with glibc's __nonnull macro by renaming the type
nullability qualifiers as follows:

  __nonnull -> _Nonnull
  __nullable -> _Nullable
  __null_unspecified -> _Null_unspecified

This is the major part of rdar://problem/21530726, but does not yet
provide the Darwin-specific behavior for the old names.

llvm-svn: 240596
2015-06-24 22:02:08 +00:00
Douglas Gregor 227fe4bc03 Make -Wnullability-completeness work with -Wsystem-headers.
rdar://problem/21134250

llvm-svn: 240187
2015-06-19 23:17:55 +00:00
Douglas Gregor 9960a8638d CF_RETURNS_[NOT_]RETAINED on a param makes the inner pointer __nullable.
That is,

  void cf2(CFTypeRef * __nullable p CF_RETURNS_NOT_RETAINED);

is equivalent to

  void cf2(CFTypeRef __nullable * __nullable p CF_RETURNS_NOT_RETAINED);

More rdar://problem/18742441

llvm-svn: 240186
2015-06-19 23:17:51 +00:00
Douglas Gregor bec595a641 Check for consistent use of nullability type specifiers in a header.
Adds a new warning (under -Wnullability-completeness) that complains
about pointer, block pointer, or member pointer declarations that have
not been annotated with nullability information (directly or inferred)
within a header that contains some nullability annotations. This is
intended to be used to help maintain the completeness of nullability
information within a header that has already been audited.

Note that, for performance reasons, this warning will underrepresent
the number of non-annotated pointers in the case where more than one
pointer is seen before the first nullability type specifier, because
we're only tracking one piece of information per header. Part of
rdar://problem/18868820.

llvm-svn: 240158
2015-06-19 18:27:45 +00:00