Related result types apply Cocoa conventions to the type of message
sends and property accesses to Objective-C methods that are known to
always return objects whose type is the same as the type of the
receiving class (or a subclass thereof), such as +alloc and
-init. This tightens up static type safety for Objective-C, so that we
now diagnose mistakes like this:
t.m:4:10: warning: incompatible pointer types initializing 'NSSet *'
with an
expression of type 'NSArray *' [-Wincompatible-pointer-types]
NSSet *array = [[NSArray alloc] init];
^ ~~~~~~~~~~~~~~~~~~~~~~
/System/Library/Frameworks/Foundation.framework/Headers/NSObject.h:72:1:
note:
instance method 'init' is assumed to return an instance of its
receiver
type ('NSArray *')
- (id)init;
^
It also means that we get decent type inference when writing code in
Objective-C++0x:
auto array = [[NSMutableArray alloc] initWithObjects:@"one", @"two",nil];
// ^ now infers NSMutableArray* rather than id
llvm-svn: 132868
This is a follow-up to r132565, and should address the rest of PR9969:
Warn about cases such as
int foo(A a, bool b) {
return a + b ? 1 : 2; // user probably meant a + (b ? 1 : 2);
}
also when + is an overloaded operator call.
llvm-svn: 132784
__builtin_astype(): Used to reinterpreted as another data type of the same size using for both scalar and vector data types.
Added test case.
llvm-svn: 132612
Warn in cases such as "x + someCondition ? 42 : 0;",
where the condition expression looks arithmetic, and has
a right-hand side that looks boolean.
This (partly) addresses http://llvm.org/bugs/show_bug.cgi?id=9969
llvm-svn: 132565
I tried to use an assert to prove that I could remove each of the
arguments I did, but ended up writing my assert with inverted logic.
Doh! Reported by Xi Wang on cfe-dev. I have manually verified the source
locations and ranges for these using -ast-dump. I tried writing a test
case that would catch these, but these expressions aren't exposed in the
c-index-test's token annotation utility.
llvm-svn: 132284
within class templates when they are necessary to complete the type of
the member. The canonical example is code like:
template <typename T> struct S {
static const int arr[];
static const int x;
static int f();
};
template <typename T> const int S<T>::arr[] = { 1, 2, 3 };
template <typename T> const int S<T>::x = sizeof(arr) / sizeof(arr[0]);
template <typename T> int S<T>::f() { return x; }
int x = S<int>::f();
We need to instantiate S<T>::arr's definition to pick up its initializer
and complete the array type. This involves new code to specially handle
completing the type of an expression where the type alone is
insufficient. It also requires *updating* the expression with the newly
completed type. Fortunately, all the other infrastructure is already in
Clang to do the instantiation, do the completion, and prune out the
unused bits of code that result from this instantiation.
This addresses the initial bug in PR10001, and will be a step to
fleshing out other cases where we need to work harder to complete an
expression's type. Who knew we still had missing C++03 "features"?
llvm-svn: 132172
provide re-usable forms of the rest of the custom validation done here.
Still no functionality changed here.
With this it should be possible to have an expression-centric code path
and a type-centric code path which don't duplicate logic.
llvm-svn: 132118
traits which uses the information embedded in the expression. Use this
to simplify several interfaces which repeated information embedded in
the expression through explicit arguments. I added an assertion that the
only extra piece of data to come in from the parser matches what is
stored in the expression. No functionality change intended here.
Also cleaned up the doxygen comments for some of these methods and some
formatting oddities.
llvm-svn: 132115
non-POD/non-trivial object throuugh a C-style varargs. The warning
itself was default-mapped to error, but can be downgraded, but we were
treating it in Sema like a hard error, silently dropping the call.
Instead, treat this problem like a warning, and do what the warning
says we do: abort at runtime. To do so, we fake up a __builtin_trap()
expression that gets evaluated as part of the argument.
llvm-svn: 131805
defaulted default constructors.
As it happens, making sure that we handle out-of-line defaulted
functions properly will involved making sure that we actually parse them
correctly, so that's coming after.
llvm-svn: 131224
We can use this to produce nice diagnostics (and try to fixit-and-recover) in
various cases where we might see "MyFunction" instead of "MyFunction()". The
changes in SemaExpr are an example of how to use isExprCallable.
llvm-svn: 130878
make sure to mark the destructor. This normally isn't required,
because the destructor should have been marked as part of the
declaration of the local, but it's necessary when the variable
is a parameter because it's the call sites that are responsible
for those destructors.
llvm-svn: 130372
member function, i.e. something of the form 'x.f' where 'f' is a non-static
member function. Diagnose this in the general case. Some of the new diagnostics
are probably worse than the old ones, but we now get this right much more
universally, and there's certainly room for improvement in the diagnostics.
llvm-svn: 130239
performs name lookup for an identifier and resolves it to a
type/expression/template/etc. in the same step. This scheme is
intended to improve both performance (by reducing the number of
redundant name lookups for a given identifier token) and error
recovery (by giving Sema a chance to correct type names before the
parser has decided that the identifier isn't a type name). For
example, this allows us to properly typo-correct type names at the
beginning of a statement:
t.c:6:3: error: use of undeclared identifier 'integer'; did you mean
'Integer'?
integer *i = 0;
^~~~~~~
Integer
t.c:1:13: note: 'Integer' declared here
typedef int Integer;
^
Previously, we wouldn't give a Fix-It because the typo correction
occurred after the parser had checked whether "integer" was a type
name (via Sema::getTypeName(), which isn't allowed to typo-correct)
and therefore decided to parse "integer * i = 0" as an expression. By
typo-correcting earlier, we typo-correct to the type name Integer and
parse this as a declaration.
Moreover, in this context, we can also typo-correct identifiers to
keywords, e.g.,
t.c:7:3: error: use of undeclared identifier 'vid'; did you mean
'void'?
vid *p = i;
^~~
void
and recover appropriately.
Note that this is very much a work-in-progress. The new
Sema::ClassifyName is only used for expression-or-declaration
disambiguation in C at the statement level. The next steps will be to
make this work for the same disambiguation in C++ (where
functional-style casts make some trouble), then push it
further into the parser to eliminate more redundant name lookups.
Fixes <rdar://problem/7963833> for C and starts us down the path of
<rdar://problem/8172000>.
llvm-svn: 130082
gcc's unused warnings which don't get emitted if the function is referenced even in an unevaluated context
(e.g. in templates, sizeof, etc.). Also, saying that a function is 'unused' because it won't get codegen'ed
is somewhat misleading.
- Don't emit 'unused' warnings for functions that are referenced in any part of the user's code.
- A warning that an internal function/variable won't get emitted is useful though, so introduce
-Wunneeded-internal-declaration which will warn if a function/variable with internal linkage is not
"needed" ('used' from the codegen perspective), e.g:
static void foo() { }
template <int>
void bar() {
foo();
}
test.cpp:1:13: warning: function 'foo' is not needed and will not be emitted
static void foo() { }
^
Addresses rdar://8733476.
llvm-svn: 129794
named by the nested-name-specifier is same or base of the class in which the member expression appears.
It seems we also had an ill-formed test case, mon dieu! Fixes rdar://8576107.
llvm-svn: 129493
for __unknown_anytype resolution to destructively modify the AST. So that's
what it does now, which significantly simplifies some of the implementation.
Normal member calls work pretty cleanly now, and I added support for
propagating unknown-ness through &.
llvm-svn: 129331
This patch authored by Eric Niebler.
Many methods on the Sema class (e.g. ConvertPropertyForRValue) take Expr
pointers as in/out parameters (Expr *&). This is especially true for the
routines that apply implicit conversions to nodes in-place. This design is
workable only as long as those conversions cannot fail. If they are allowed
to fail, they need a way to report their failures. The typical way of doing
this in clang is to use an ExprResult, which has an extra bit to signal a
valid/invalid state. Returning ExprResult is de riguour elsewhere in the Sema
interface. We suggest changing the Expr *& parameters in the Sema interface
to ExprResult &. This increases interface consistency and maintainability.
This interface change is important for work supporting MS-style C++
properties. For reasons explained here
<http://lists.cs.uiuc.edu/pipermail/cfe-dev/2011-February/013180.html>,
seemingly trivial operations like rvalue/lvalue conversions that formerly
could not fail now can. (The reason is that given the semantics of the
feature, getter/setter method lookup cannot happen until the point of use, at
which point it may be found that the method does not exist, or it may have the
wrong type, or overload resolution may fail, or it may be inaccessible.)
llvm-svn: 129143
The idea is that you can create a VarDecl with an unknown type, or a
FunctionDecl with an unknown return type, and it will still be valid to
access that object as long as you explicitly cast it at every use. I'm
still going back and forth about how I want to test this effectively, but
I wanted to go ahead and provide a skeletal implementation for the LLDB
folks' benefit and because it also improves some diagnostic goodness for
placeholder expressions.
llvm-svn: 129065
which versions of an OS provide a certain facility. For example,
void foo()
__attribute__((availability(macosx,introduced=10.2,deprecated=10.4,obsoleted=10.6)));
says that the function "foo" was introduced in 10.2, deprecated in
10.4, and completely obsoleted in 10.6. This attribute ties in with
the deployment targets (e.g., -mmacosx-version-min=10.1 specifies that
we want to deploy back to Mac OS X 10.1). There are several concrete
behaviors that this attribute enables, as illustrated with the
function foo() above:
- If we choose a deployment target >= Mac OS X 10.4, uses of "foo"
will result in a deprecation warning, as if we had placed
attribute((deprecated)) on it (but with a better diagnostic)
- If we choose a deployment target >= Mac OS X 10.6, uses of "foo"
will result in an "unavailable" warning (in C)/error (in C++), as
if we had placed attribute((unavailable)) on it
- If we choose a deployment target prior to 10.2, foo() is
weak-imported (if it is a kind of entity that can be weak
imported), as if we had placed the weak_import attribute on it.
Naturally, there can be multiple availability attributes on a
declaration, for different platforms; only the current platform
matters when checking availability attributes.
The only platforms this attribute currently works for are "ios" and
"macosx", since we already have -mxxxx-version-min flags for them and we
have experience there with macro tricks translating down to the
deprecated/unavailable/weak_import attributes. The end goal is to open
this up to other platforms, and even extension to other "platforms"
that are really libraries (say, through a #pragma clang
define_system), but that hasn't yet been designed and we may want to
shake out more issues with this narrower problem first.
Addresses <rdar://problem/6690412>.
As a drive-by bug-fix, if an entity is both deprecated and
unavailable, we only emit the "unavailable" diagnostic.
llvm-svn: 128127
overload, so that we actually do the resolution for full expressions
and emit more consistent, useful diagnostics. Also fixes an IRGen
crasher, where Sema wouldn't diagnose a resolvable bound member
function template-id used in a full-expression (<rdar://problem/9108698>).
llvm-svn: 127747
operands to a binary expression; it doesn't make sense in all
contexts. The right answer would be to see if the user forgot at ().
Fixes <rdar://problem/9136502>.
llvm-svn: 127740
declaration as this results in a confusing error message,
instead of message related to missing property declaration.
// rdar://9106929
llvm-svn: 127682
UnresolvedLookupExpr and UnresolvedMemberExpr.
Also, improve the computation that checks whether the base of a member
expression (either unresolved or dependent-scoped) is implicit. The
previous check didn't cover all of the cases we use in our
representation, which threw off source-location information for these
expressions (which, in turn, caused some breakage in libclang's token
annotation).
llvm-svn: 126681
CXXDependentScopeMemberExpr, and clean up instantiation of
nested-name-specifiers with dependent template specialization types in
the process.
llvm-svn: 126663
don't let calls to such functions go down the normal type-checking path.
Test this out with __builtin_classify_type and __builtin_constant_p.
llvm-svn: 126539
expressions. Consider the code:
int64_t i = 10 << 30;
This compiles fine, but most developers expect it to produce the value
for 10 gigs, not -2 gigs. This is actually undefined behavior because
the LHS is a signed integer type.
The warning is currently gated behind -Wshift-overflow.
There is a special case where only the sign bit is overridden that gets
a custom error message and is by default ignored. This case is much less
likely to cause observed buggy behavior, it's just undefined behavior
according to the spec. This warning can be enabled with
-Wshift-sign-overflow.
Original patch by Oleg Slezberg, with style tweaks and some correctness
fixes by me.
llvm-svn: 126342
diagnostics that occur in unreachable code (e.g., -Warray-bound).
We only pay the cost of doing the reachability analysis when we issue one of these diagnostics.
llvm-svn: 126290
* Flag indicating 'we're parsing this auto typed variable's initializer' moved from VarDecl to Sema
* Temporary template parameter list for auto deduction is now allocated on the stack.
* Deduced 'auto' types are now uniqued.
llvm-svn: 126139
initializers just because they don't have a proper out-of-line definition.
Such code is technically ill-formed but is too common and too unlikely to be
a problem to be seriously worth worrying about.
llvm-svn: 126137
without defining them. This should be an error, but I'm paranoid about
"uses" that end up not actually requiring a definition. I'll revisit later.
Also, teach IR generation to not set internal linkage on variable
declarations, just for safety's sake. Doing so produces an invalid module
if the variable is not ultimately defined.
Also, fix several places in the test suite where we were using internal
functions without definitions.
llvm-svn: 126016