This is still an experimental attribute, but I wanted it in tree
for review. It may still get yanked.
This attribute can only be applied to a class @interface, not
a class extension or category. It does not change the type
system rules for Objective-C, but rather the implementation checking
for Objective-C classes that explicitly conform to a protocol.
During protocol conformance checking, clang recursively searches
up the class hierarchy for the set of methods that compose
a protocol. This attribute will cause the compiler to not consider
the methods contributed by a super class, its categories, and those
from its ancestor classes. Thus this attribute is used to force
subclasses to redeclare (and hopefully re-implement) methods if
they decide to explicitly conform to a protocol where some of those
methods may be provided by a super class.
This attribute intentionally leaves out properties, which are associated
with state. This attribute only considers methods (at least right now)
that are non-property accessors. These represent methods that "do something"
as dictated by the protocol. This may be further refined, and this
should be considered a WIP until documentation gets written or this
gets removed.
llvm-svn: 195533
attribute on method declaration and implementation
match. This makes no sense. Most annotations are
meant for declarations only and one is for implementation.
This has been constant source of regresions and hackery to
get around special cases. I am removing this check.
Such checks must be done on a case by case basis and
when it makes sense. For example, it makes sense
for availability/deprecated and I will file a radar
for that. // rdar://15531984
llvm-svn: 195524
whose semantic is currently identical to objc_bridge,
but their differences may manifest down the road with
further enhancements. // rdar://15498044
llvm-svn: 195376
After implementing this patch, a few concerns about the language
feature itself emerged in my head that I had previously not considered.
I want to resolve those design concerns first before having
a half-designed language feature in the tree.
llvm-svn: 195328
The idea is to allow a class to stipulate that its methods (and those
of its parents) cannot be used for protocol conformance in a subclass.
A subclass is then explicitly required to re-implement those methods
of they are present in the class marked with this attribute.
Currently the attribute can only be applied to an @interface, and
not a category or class extension. This is by design. Unlike
protocol conformance, where a category can add explicit conformance
of a protocol to class, this anti-conformance really needs to be
observed uniformly by all clients of the class. That's because
the absence of the attribute implies more permissive checking of
protocol conformance.
This unfortunately required changing method lookup in ObjCInterfaceDecl
to take an optional protocol parameter. This should not slow down
method lookup in most cases, and is just used for protocol conformance.
llvm-svn: 195323
- If a deprecated class refers to another deprecated class, do not warn.
- @implementations of a deprecated class can refer to other deprecated things.
Fixes <rdar://problem/15407366> and <rdar://problem/15466783>.
llvm-svn: 195259
Also refine test case to capture the intention of this suppression. Essentially
some developers use __bridge_transfer as if it were a safe CFRelease.
llvm-svn: 194663
-fobjc-subscripting-legacy-runtime which is off
by default and on only when using ObjectiveC
legacy runtime. Use this flag to allow
array and dictionary subscripting and disallow
objectiveC pointer arithmatic in ObjectiveC
legacy runtime. // rdar://15363492
llvm-svn: 193889
into a separate "parse an attribute that takes a type argument" codepath. This
results in both codepaths being a lot cleaner and simpler, and fixes some bugs
where the type argument handling bled into the expression argument handling and
caused us to both accept invalid and reject valid attribute arguments.
llvm-svn: 193731
This patch fixes PR17019. When doing typo correction, Sema::CorrectTypo uses
correction already seen for the same typo. This causes problems if that
correction is from another scope and cannot be accessed in the current.
llvm-svn: 192594
(assign/unsafe_unretained/weak/retain/strong/copy) in super class
to be overridden by a property with any explicit ownership in the
subclass. // rdar://15014468
llvm-svn: 191971
declared in a typedef declaraton used as super
class of an ObjC class. Curretnly, these protocols
are dropped from the class hierarchy. Test shows that
it is now included. // rdar://15051465
llvm-svn: 191395
of ObjectiveC properties to mean annotation of
NS_RETURNS_INNER_POINTER on its synthesized getter.
This also facilitates more migration to properties when
methods are annotated with NS_RETURNS_INNER_POINTER.
// rdar://14990439
llvm-svn: 191009
This expands very slightly what -Wtautological-compare considers to be
tautological to include implicit accesses to C++ fields and ObjC ivars.
I don't want to turn this into a full expression-identity check, but
these additions seem pretty well-contained, and maintain the theme
of checking for "x == x".
<rdar://problem/14431127>
llvm-svn: 190118
properties (direct or indirect) setter/getter (or declared
methods as well) are seen by the method implementation type
matching logic before declaration of method in super class
is seen. This fixes the warning coming out of that method mismatch.
// rdar://14650159
llvm-svn: 188438
function: it can't be 'void' and it can't be an initializer list. We give a
hard error for these rather than treating them as undefined behavior (we can
and probably should do the same for non-POD types in C++11, but as of this
change we don't).
Slightly rework the checking of variadic arguments in a function with a format
attribute to ensure that certain kinds of format string problem (non-literal
string, too many/too few arguments, ...) don't suppress this error.
llvm-svn: 187735
This is the same way GenericSelectionExpr works, and it's generally a
more consistent approach.
A large part of this patch is devoted to caching the value of the condition
of a ChooseExpr; it's needed to avoid threading an ASTContext into
IgnoreParens().
Fixes <rdar://problem/14438917>.
llvm-svn: 186738
Summary: In ARC mode, clang emits a warning if the result of an 'init' method is unused but miss cases where the method does not follows the Cocoa naming convention but is properly declared as an init family method.
CC: cfe-commits, eli.friedman
Differential Revision: http://llvm-reviews.chandlerc.com/D1163
llvm-svn: 186718
method declaration into its implementation to
prevent a bogus warning about mismatched attributes.
then make sure the warning about missing call to super comes out
of the method implementation. // rdar://14251387
llvm-svn: 185974
-performSelector: and friends return a value that is boxed as an Objective-C
pointer. Sometimes it is an Objective-C pointer, sometimes it isn't.
Some clients may wish to silence this warning based on calling
this method.
Fixes <rdar://problem/14147304>
llvm-svn: 184789
in addition of receiver having static type, but also when
receiver has dynamic type (of 'id' variety) as well as when
receiver is of 'Class' type vareity. // rdar://7853549
llvm-svn: 184195
protocols that declare the same property of incompatible
types, issue a warning when class implementation synthesizes
the property. // rdar://13075400
llvm-svn: 182316
found for a receiver, note where receiver class
is declaraed (this is most common when receiver is a forward
class). // rdar://3258331
llvm-svn: 181847
This change partly addresses a heinous problem we have with the
parsing of attribute arguments that are a lone identifier. Previously,
we would end up parsing the 'align' attribute of this as an expression
"(Align)":
template<unsigned Size, unsigned Align>
class my_aligned_storage
{
__attribute__((align((Align)))) char storage[Size];
};
while this would parse as a "parameter name" 'Align':
template<unsigned Size, unsigned Align>
class my_aligned_storage
{
__attribute__((align(Align))) char storage[Size];
};
The code that handles the alignment attribute would completely ignore
the parameter name, so the while the first of these would do what's
expected, the second would silently be equivalent to
template<unsigned Size, unsigned Align>
class my_aligned_storage
{
__attribute__((align)) char storage[Size];
};
i.e., use the maximal alignment rather than the specified alignment.
Address this by sniffing the "Args" provided in the TableGen
description of attributes. If the first argument is "obviously"
something that should be treated as an expression (rather than an
identifier to be matched later), parse it as an expression.
Fixes <rdar://problem/13700933>.
llvm-svn: 180973
This change partly addresses a heinous problem we have with the
parsing of attribute arguments that are a lone identifier. Previously,
we would end up parsing the 'align' attribute of this as an expression
"(Align)":
template<unsigned Size, unsigned Align>
class my_aligned_storage
{
__attribute__((align((Align)))) char storage[Size];
};
while this would parse as a "parameter name" 'Align':
template<unsigned Size, unsigned Align>
class my_aligned_storage
{
__attribute__((align(Align))) char storage[Size];
};
The code that handles the alignment attribute would completely ignore
the parameter name, so the while the first of these would do what's
expected, the second would silently be equivalent to
template<unsigned Size, unsigned Align>
class my_aligned_storage
{
__attribute__((align)) char storage[Size];
};
i.e., use the maximal alignment rather than the specified alignment.
Address this by sniffing the "Args" provided in the TableGen
description of attributes. If the first argument is "obviously"
something that should be treated as an expression (rather than an
identifier to be matched later), parse it as an expression.
Fixes <rdar://problem/13700933>.
llvm-svn: 180970
Previously it would point to the left bracket or the receiver, which can be particularly
problematic if the receiver is a block literal and we end up point the diagnostic far away
for the selector that is complaining about.
rdar://13620447
llvm-svn: 180833
patch -n r180198.
When reporting on missing property accessor implementation in
categories, do not report when they are declared in primary class,
class's protocol, or one of it super classes or in of the other
categories. // rdar://13713098
llvm-svn: 180580
categories, do not report when they are declared in primary class,
class's protocol, or one of it super classes. This is because,
its class is going to implement them. // rdar://13713098
llvm-svn: 180198
VerifyDiagnosticConsumer previously would not check that the diagnostic and
its matching directive referenced the same source file. Common practice was
to create directives that referenced other files but only by line number,
and this led to problems such as when the file containing the directive
didn't have enough lines to match the location of the diagnostic in the
other file, leading to bizarre file formatting and other oddities.
This patch causes VerifyDiagnosticConsumer to match source files as well as
line numbers. Therefore, a new syntax is made available for directives, for
example:
// expected-error@file:line {{diagnostic message}}
This extends the @line feature where "file" is the file where the diagnostic
is generated. The @line syntax is still available and uses the current file
for the diagnostic. "file" can be specified either as a relative or absolute
path - although the latter has less usefulness, I think! The #include search
paths will be used to locate the file and if it is not found an error will be
generated.
The new check is not optional: if the directive is in a different file to the
diagnostic, the file must be specified. Therefore, a number of test-cases
have been updated with regard to this.
This closes out PR15613.
llvm-svn: 179677
When we are in a implementation, we check the global method pool whether there were category
methods with the same selector. If there were none (common case) we don't need to do lookups for
overridden methods again.
Note that for an interface method (if we don't encounter its implementation), it is considered that
it overrides methods that were declared before it, not for category methods introduced after it.
This is tradeoff in favor of performance, since it is expensive to do lookups in case there was a
category, and moving the global method pool to ASTContext (so we can check it) would increase complexity.
rdar://13508196
llvm-svn: 179654
This reverts commit r179436.
Due to caching, it was possible that we could miss overridden methods that
were introduced by categories later on.
Along with reverting the commit I also included a test case that would have caught this.
llvm-svn: 179547
when result type of protocol property and getter method
differ by fixing a more serious problem. When a forward
protocol declaration comes between its definition and
its use in class protocol list, the forward protocol
ast was being used in building the protocol list.
// rdar://12522752
llvm-svn: 179108
New rule:
- Method decls in @implementation are considered "redeclarations"
and inherit deprecated/availability from the @interface.
- All other cases are consider overrides, which do not inherit
deprecated/availability. For example:
(a) @interface redeclares a method in an adopted protocol.
(b) A subclass redeclares a method in a superclass.
(c) A protocol redeclares a method from another protocol it adopts.
The idea is that API authors should have the ability to easily
move availability/deprecated up and down a class/protocol hierarchy.
A redeclaration means that the availability/deprecation is a blank
slate.
Fixes <rdar://problem/13574571>
llvm-svn: 178937
'isa' ivar is accessed provided it is the first
ivar. Fixit hint will follow in another patch.
This is continuation of // rdar://13503456
llvm-svn: 178313
Previously all unimplemented methods for a class were grouped under
a single warning, with all the unimplemented methods mentioned
as notes. Based on feedback from users, most users would like
a separate warning for each method, with a note pointing back to
the original method declaration.
Implements <rdar://problem/13350414>
llvm-svn: 178097
is issused for on overriding 'readwrite'
property which is not auto-synthesized.
Buttom line is that if hueristics determine
that there will be a user implemented setter,
no warning will be issued. // rdar://13388503
llvm-svn: 177662
This created 2 issues:
1) Performance issue, since typo-correction with PCH/modules is rather expensive.
2) Correctness issue, since if it managed to "correct" 'super' then bogus compiler errors would
be emitted, like this:
3.m:8:3: error: unknown type name 'super'; did you mean 'super1'?
super.x = 0;
^~~~~
super1
t3.m:5:13: note: 'super1' declared here
typedef int super1;
^
t3.m:8:8: error: expected identifier or '('
super.x = 0;
^
llvm-svn: 177126
when property autosynthesis does not synthesize a property.
When property is declared 'readonly' in a super class and
is redeclared 'readwrite' in a subclass. When a property
autosynthesis causes it to share 'ivar' with another property.
// rdar://13388503
llvm-svn: 176889
so that it looks through certain syntactic forms and applies
even if normal inference would have succeeded.
There is potential for source incompatibility from this
change, but overall we feel that it produces a much
cleaner and more defensible result, and the block
compatibility rules should curb a lot of the potential
for annoyance.
rdar://13200889
llvm-svn: 176743
whether we already have a method. Fixes a bug where we were
failing to properly contextually convert a message receiver
during template instantiation.
As a side-effect, we now actually perform correct method lookup
after adjusting a message-send to integral or non-ObjC pointer
types (legal outside of ARC).
rdar://13305374
llvm-svn: 176339
of block declarators. Document the rule we use.
Also document the rule that Doug implemented a few weeks ago
which drops ownership qualifiers on function result types.
rdar://10127067
llvm-svn: 176336
This reduces the "ambiguous reference" errors (which are rather strange in C/ObjC) and fixes an assertion hit
with an invalid code test case.
llvm-svn: 175869
the "nonatomic" attribute in property redeclaration
in class extension. Also, improved on diagnostics in
this area while at it. // rdar://13156292
llvm-svn: 174821
"auto-synthesized may not work correctly with 'nib' loader"
when 'readonly' property is redeclared 'readwrite' in class
extension. // rdar://13123861
llvm-svn: 174775
return type of a function by canonicalizing them away. They are
useless anyway, and conflict with our rules for template argument
deduction and __strong. Fixes <rdar://problem/12367446>.
llvm-svn: 172768
overriding and overridden method, allow the overridden method to have
a narrower contract (introduced earlier, deprecated/obsoleted later)
than the overriding method. Fixes <rdar://problem/12992023>.
llvm-svn: 172567
Along the way, fix a bug in CheckLiteralKind(), previously in diagnoseObjCLiteralComparison, where we didn't ignore parentheses
in boxed expressions for purpose of classification.
In other words, both @42 and @(42) should be classified as numeric
literals.
llvm-svn: 170931
has inconsistent ownership with the backing ivar, point the error location to the
ivar.
Pointing to the ivar (instead of the @synthesize) is better since this is where a fix is needed.
Also provide the location of @synthesize via a note.
This also fixes the problem where an auto-synthesized property would emit an error without
any location.
llvm-svn: 170039
For most cases where a conversion specifier doesn't match an argument,
we usually guess that the conversion specifier is wrong. However, if
the argument is an integer type and the specifier is %C, it's likely
the user really did mean to print the integer as a character.
(This is more common than %c because there is no way to specify a unichar
literal -- you have to write an integer literal, such as '0x2603',
and then cast it to unichar.)
This does not change the behavior of %S, since there are fewer cases
where printing a literal Unicode *string* is necessary, but this could
easily be changed in the future.
<rdar://problem/11982013>
llvm-svn: 169400
This warning was failing to fire under ARC because of the implicit
lifetime casts added around the object literal expression.
<rdar://problem/11300873>, again.
llvm-svn: 167648
Previously, the warning would erroneously fire on this:
for (Test *a in someArray)
use(a.weakProp);
...because it looks like the same property is being accessed over and over.
However, clearly this is not the case. We now ignore loops like this for
local variables, but continue to warn if the base object is a parameter,
global variable, or instance variable, on the assumption that these are
not repeatedly usually assigned to within loops.
Additionally, do-while loops where the condition is 'false' are not really
loops at all; usually they're just used for semicolon-swallowing macros or
using "break" like "goto".
<rdar://problem/12578785&12578849>
llvm-svn: 166942
Also, unify ObjCShouldCallSuperDealloc and ObjCShouldCallSuperFinalize.
The two have identical behavior and will never be active at the same time.
There's one last simplification now, which is that if we see a call to
[super foo] and we are currently in a method named 'foo', we will
/unconditionally/ clear the ObjCShouldCallSuper flag, rather than check
first to see if we're in a method where calling super is required. There's
no reason to pay the extra lookup price here.
llvm-svn: 166285
This is a "safe" pattern, or at least one that cannot be helped by using
a strong local variable. However, if the single read is within a loop,
it should /always/ be treated as potentially dangerous.
<rdar://problem/12437490>
llvm-svn: 165719
Previously, [foo weakProp] was not being treated the same as foo.weakProp.
Now, for every explicit message send, we check if it's a property access,
and if so, if the property is weak. Then for every assignment of a
message, we have to do the same thing again.
This is a potentially expensive increase because determining whether a
method is a property accessor requires searching through the methods it
overrides. However, without it -Warc-repeated-use-of-weak will miss cases
from people who prefer not to use dot syntax. If this turns out to be
too expensive, we can try caching the result somewhere, or even lose
precision by not checking superclass methods. The warning is off-by-default,
though.
<rdar://problem/12407765>
llvm-svn: 165718
Then, switch users of PropertyIfSetterOrGetter and LookupPropertyDecl
(the latter by name) over to findPropertyDecl. This actually makes
-Wreceiver-is-weak a bit stronger than it was before.
llvm-svn: 165628
Old algorithm:
1. See if the name looks like a getter or setter.
2. Use the name to look up a property in the current ObjCContainer
and all its protocols.
3. If the current container is an interface, also look in all categories
and superclasses (and superclass categories, and so on).
New algorithm:
1. See if the method is marked as a property accessor. If so, look through
all properties in the current container and find one that has a matching
selector.
2. Find all overrides of the method using ObjCMethodDecl's
getOverriddenMethods. This collects methods in superclasses and protocols
(as well as superclass categories, which isn't really necessary), and
checks if THEY are accessors. This part is not done recursively, since
getOverriddenMethods is already recursive.
This lets us handle getters and setters that do not match the property
names.
llvm-svn: 165627
New output:
warning: weak property may be unpredictably set to nil
note: property declared here
note: assign the value to a strong variable to keep the object alive
during use
<rdar://problem/12277204>
llvm-svn: 164857
Like properties, loading from a weak ivar twice in the same function can
give you inconsistent results if the object is deallocated between the
two loads. It is safer to assign to a strong local variable and use that.
Second half of <rdar://problem/12280249>.
llvm-svn: 164855
The motivating example:
if (self.weakProp)
use(self.weakProp);
As with any non-atomic test-then-use, it is possible a weak property to be
non-nil at the 'if', but be deallocated by the time it is used. The correct
way to write this example is as follows:
id tmp = self.weakProp;
if (tmp)
use(tmp);
The warning is controlled by -Warc-repeated-use-of-receiver, and uses the
property name and base to determine if the same property on the same object
is being accessed multiple times. In cases where the base is more
complicated than just a single Decl (e.g. 'foo.bar.weakProp'), it picks a
Decl for some degree of uniquing and reports the problem under a subflag,
-Warc-maybe-repeated-use-of-receiver. This gives a way to tune the
aggressiveness of the warning for a particular project.
The warning is not on by default because it is not flow-sensitive and thus
may have a higher-than-acceptable rate of false positives, though it is
less noisy than -Wreceiver-is-weak. On the other hand, it will not warn
about some cases that may be legitimate issues that -Wreceiver-is-weak
will catch, and it does not attempt to reason about methods returning weak
values.
Even though this is not a real "analysis-based" check I've put the bug
emission code in AnalysisBasedWarnings for two reasons: (1) to run on
every kind of code body (function, method, block, or lambda), and (2) to
suggest that it may be enhanced by flow-sensitive analysis in the future.
The second (smaller) half of this work is to extend it to weak locals
and weak ivars. This should use most of the same infrastructure.
Part of <rdar://problem/12280249>
llvm-svn: 164854
Retain cycles happen in the case where a block is persisted past its
life on the stack, and the way that occurs is by copying the block.
We should thus look through any explicit copies we see.
Note that Block_copy is actually a type-safe wrapper for _Block_copy,
which does all the real work.
<rdar://problem/12219663>
llvm-svn: 164039
Specifically, this should warn:
__block block_t a = ^{ a(); };
Furthermore, this case which previously warned now does not, since the value
of 'b' is captured before the assignment occurs:
block_t b; // not __block
b = ^{ b(); };
(This will of course warn under -Wuninitialized, as before.)
<rdar://problem/11015883>
llvm-svn: 163962
Objective-C related to NSException.
Fixes <rdar://problem/12287498>
I debated whether or not this logic should be sunk into the CFG
itself. It's not clear if we should, as different analyses may
wish to have different policies. We can re-evaluate this in the
future.
llvm-svn: 163760
in classes. Use it to flag those method implementations which don't
contain call to 'super' if they have 'super' class and it has the method
with this attribute set. This is wip. // rdar://6386358
llvm-svn: 163434
and when used in property type declaration, is handled as type
attribute. Do not issue the warning when declaraing the property.
// rdar://12173491
llvm-svn: 162801
class extensions a little. clang now allows readonly property
with no ownership rule (assign, unsafe_unretained, weak, retain,
strong, or copy) with a readwrite property with an ownership rule.
// rdar://12103400
llvm-svn: 162319
We handled the builtin version of this function in r157968, but the builtin
isn't used when compiling as -fno-constant-cfstrings.
This should complete <rdar://problem/6157200>.
llvm-svn: 161525
type of generated call to super dealloc is 'void'
and asserts if user's dealloc is not of 'void type.
This rule must be enforced in clang front-end (with a
fixit) if this is not the case, instead of asserting in CodeGen.
// rdar://11987838
llvm-svn: 160993
Argyrios Kyrtzidis