by ensuring DiagnoseUseOfDecl is called both on the found decl and the
decl being used (i.e the specialization in the case of member templates) whenever they are different.
Per the exchange captured in
http://lists.cs.uiuc.edu/pipermail/cfe-commits/Week-of-Mon-20130610/081636.html
a more comprehensive fix that allows both decls to be passed into DiagnoseUseOfDecl is (or should be) forthcoming relatively soon.
llvm-svn: 184043
Previously, it only ever fired for zeros which formed null pointers.
Now, hilariously, in C++98 this was almost anything. Including tricks
like warning on the divisor in this code:
typedef char c3[3];
size_t f(c3* ptr) {
return (sizeof(ptr) / sizeof(*ptr)) / (size_t)(!(sizeof(ptr) % sizeof(*ptr)));
}
Why the RHS of the outer divide is a null pointer constant is a sordid
tale of sorrow. Anyways, the committee fixed this for C++11 and onward
as part of core isssue 903, and Richard recently implemented this fix
causing the warning to go away here (and elsewhere).
This patch restores the warning here and adds it for numerous other
somewhat obvious gaffes:
int g(int x) {
return x / (int)(0.0);
}
The patch is essentially just using the full power of our constant
folding in Clang to produce the warning, but insisting that it must fold
to an *integer* which is zero so that we don't get false positives
anywhere.
llvm-svn: 183970
implicit definition of a copy operation is deprecated. Add a warning for this
to -Wdeprecated. This warning is disabled by default for now, pending
investigation into how common this situation is.
llvm-svn: 183884
- 'register' storage class
- dynamic exception specifications
Only the former check is enabled by default for now (the latter might be quite noisy).
llvm-svn: 183881
Introduce CXXStdInitializerListExpr node, representing the implicit
construction of a std::initializer_list<T> object from its underlying array.
The AST representation of such an expression goes from an InitListExpr with a
flag set, to a CXXStdInitializerListExpr containing a MaterializeTemporaryExpr
containing an InitListExpr (possibly wrapped in a CXXBindTemporaryExpr).
This more detailed representation has several advantages, the most important of
which is that the new MaterializeTemporaryExpr allows us to directly model
lifetime extension of the underlying temporary array. Using that, this patch
*drastically* simplifies the IR generation of this construct, provides IR
generation support for nested global initializer_list objects, fixes several
bugs where the destructors for the underlying array would accidentally not get
invoked, and provides constant expression evaluation support for
std::initializer_list objects.
llvm-svn: 183872
CXXCtorInitializers to the point where we perform the questionable lifetime
extension. This exposed a selection of false negatives in the warning.
llvm-svn: 183869
This warning triggers on the logical not of a non-boolean expression on the
left hand side of comparison. Often, the user meant to negate the comparison,
not just the left hand side of the comparison. Two notes are also emitted,
the first with a fix-it to add parentheses around the comparison, and the other
to put parenthesis around the not expression to silence the warning.
bool not_equal(int x, int y) {
return !x == y; // warn here
}
return !(x == y); // first fix-it, to negate comparison.
return (!x) == y; // second fix-it, to silence warning.
llvm-svn: 183688
This became allowed by accident in r131201, but triggers an assert.
That patch added an exception to allow conversion from pointers to
narrow integral types for MSVC compatibility. However, a pointer can
already be converted to bool in a civilized manner; allowing conversion
via reinterpret_cast is a bad idea.
Fixes PR16222.
llvm-svn: 183394
must be initialized by a constant expression (not just a core constant
expression), because we're going to emit it as a global. Core issue for this is
pending.
llvm-svn: 183388
handle temporaries which have been lifetime-extended to static storage duration
within constant expressions. This correctly handles nested lifetime extension
(through reference members of aggregates in aggregate initializers) but
non-constant-expression emission hasn't yet been updated to do the same.
llvm-svn: 183283
Still missing cases for templates, but this is a step in the right
direction. Also omits suggestions that would be ambiguous (eg: void
func(int = 0); + void func(float = 0); func;)
llvm-svn: 183173
This matches the behavior of MemberExpr and makes diagnostics such as
"reference to non-static member function must be called" more legible in
the case that the base & member are split over multiple lines (prior to
this change the diagnostic would point to the base, not the member -
making it very unclear in chained multi-line builder-style calls)
llvm-svn: 183149
materialized temporary with the corresponding MaterializeTemporaryExpr. This is
groundwork for providing C++11's guaranteed static initialization for global
references bound to lifetime-extended temporaries (if the initialization is a
constant expression).
In passing, fix a couple of bugs where some evaluation failures didn't trigger
diagnostics, and a rejects-valid where potential constant expression testing
would assume that it knew the dynamic type of *this and would reject programs
which relied on it being some derived type.
llvm-svn: 183093
clang would incorrectly not allow the following:
int x = true ? (throw 1) : 2;
The problem exists because we don't see beyond the parens.
This, in turn, causes us to believe that we are choosing between void
and int which we diagnose as an error.
Instead, allow clang to see the 'throw' inside the parens.
llvm-svn: 183085
The testcase in PR16060 points out that while template arguments can
show that a type is not externally visible, the standards still says
they have external linkage.
In terms of our implementation, it means that we should merge just the
isExternallyVisible bit, not the formal linkage.
llvm-svn: 182962
references. What's more, they use this language extension in their
ATL header files (which come as part of MFC and the Win32 SDK). This patch implements support for the Microsoft extension, and addresses PR13737.
llvm-svn: 182936
John noticed that the fix for pr15930 (r181981) didn't handle indirect
uses of local types. For example, a pointer to local struct, or a
function that returns it.
One way to implement this would be to recursively look for local
types. This would look a lot like the linkage computation itself for
types.
To avoid code duplication and utilize the existing linkage cache, this
patch just makes the computation of "type with no linkage but
externally visible because it is from an inline function" part of the
linkage computation itself.
llvm-svn: 182711
* Treat _Atomic(T) as a literal type if T is a literal type.
* Evaluate expressions of this type properly.
* Fix a lurking bug where we built completely bogus ASTs for converting to
_Atomic types in C++ in some cases, caught by the tests for this change.
llvm-svn: 182541
common function. The C++1y contextual implicit conversion rules themselves are
not yet implemented, however.
This also fixes a subtle bug where template instantiation context notes were
dropped for diagnostics coming from conversions for integral constant
expressions -- we were implicitly slicing a SemaDiagnosticBuilder into a
DiagnosticBuilder when producing these diagnostics, and losing their context
notes in the process.
llvm-svn: 182406
While the C++ standard requires that this lookup take place only at the
definition point of a virtual destructor (C++11 [class.dtor]p12), the
Microsoft ABI may require the compiler to emit a deleting destructor
for any virtual destructor declared in the TU, including ones without
a body, requiring an operator delete() lookup for every virtual
destructor declaration. The result of the lookup should be the same
no matter which declaration is used (except in weird corner cases).
This change will cause us to reject some valid TUs in Microsoft ABI
mode, e.g.:
struct A {
void operator delete(void *);
};
struct B {
void operator delete(void *);
};
struct C : A, B {
virtual ~C();
};
As Richard points out, every virtual function declared in a TU
(including this virtual destructor) is odr-used, so it must be defined
in any program which declares it, or the program is ill formed, no
diagnostic required. Because we know that any definition of this
destructor will cause the lookup to fail, the compiler can choose to
issue a diagnostic here.
Differential Revision: http://llvm-reviews.chandlerc.com/D822
llvm-svn: 182270
selectany only applies to externally visible global variables. It has
the effect of making the data weak_odr.
The MSDN docs suggest that unused definitions can only be dropped at
linktime, so Clang uses weak instead of linkonce. MSVC optimizes away
references to constant selectany data, so it must assume that there is
only one definition, hence weak_odr.
Reviewers: espindola
Differential Revision: http://llvm-reviews.chandlerc.com/D814
llvm-svn: 182266
assert_exclusive_lock and assert_shared_lock. These attributes are used to
mark functions that dynamically check (i.e. assert) that a lock is held.
llvm-svn: 182170
instantiate the inherited constructor template and mark that as the constructor
which the instantiated specialization is inheriting. This fixes a
crash-on-valid when trying to compute the exception specification of a
specialization of the inheriting constructor.
llvm-svn: 182072
This commit improves Clang's diagnostics for string initialization.
Where it would previously say:
/tmp/a.c:3:9: error: array initializer must be an initializer list
wchar_t s[] = "Hi";
^
/tmp/a.c:4:6: error: array initializer must be an initializer list or string literal
char t[] = L"Hi";
^
It will now say
/tmp/a.c:3:9: error: initializing wide char array with non-wide string literal
wchar_t s[] = "Hi";
^
/tmp/a.c:4:6: error: initializing char array with wide string literal
char t[] = L"Hi";
^
As a bonus, it also fixes the fact that Clang would previously reject
this valid C11 code:
char16_t s[] = u"hi";
char32_t t[] = U"hi";
because it would only recognize the built-in types for char16_t and
char32_t, which do not exist in C.
llvm-svn: 181880
The most common (non-buggy) case are where such objects are used as
return expressions in bool-returning functions or as boolean function
arguments. In those cases I've used (& added if necessary) a named
function to provide the equivalent (or sometimes negative, depending on
convenient wording) test.
DiagnosticBuilder kept its implicit conversion operator owing to the
prevalent use of it in return statements.
One bug was found in ExprConstant.cpp involving a comparison of two
PointerUnions (PointerUnion did not previously have an operator==, so
instead both operands were converted to bool & then compared). A test
is included in test/SemaCXX/constant-expression-cxx1y.cpp for the fix
(adding operator== to PointerUnion in LLVM).
llvm-svn: 181869
inefficient; we perform a linear scan of switch labels to find the one matching
the condition, and then walk the body looking for that label. Both parts should
be straightforward to optimize.
llvm-svn: 181671
MSVC provides __wchar_t. This is the same as the built-in wchar_t type
from C++, but it is also available with -fno-wchar and in C.
The commit changes ASTContext to have two different types for this:
- WCharTy is the built-in type used for wchar_t in C++ and __wchar_t.
- WideCharTy is the type of a wide character literal. In C++ this is
the same as WCharTy, and in C it is an integer type compatible with
the type in <stddef.h>.
This fixes PR15815.
llvm-svn: 181587
return all the overloads instead of just picking the first possible declaration.
This removes an invalid note (and on occasion other invalid diagnostics) and
also makes clang's parsing recovery behave as if the text from its fixit were
applied.
llvm-svn: 181370
Previously, this compound literal expression (a GNU extension in C++):
(AggregateWithDtor){1, 2}
resulted in this AST:
`-CXXBindTemporaryExpr [...] 'struct Point' (CXXTemporary [...])
`-CompoundLiteralExpr [...] 'struct AggregateWithDtor'
`-CXXBindTemporaryExpr [...] 'struct AggregateWithDtor' (CXXTemporary [...])
`-InitListExpr [...] 'struct AggregateWithDtor'
|-IntegerLiteral [...] 'int' 1
`-IntegerLiteral [...] 'int' 2
Note the two CXXBindTemporaryExprs. The InitListExpr is really part of the
CompoundLiteralExpr, not an object in its own right. By introducing a new
entity initialization kind in Sema specifically for compound literals, we
avoid the treatment of the inner InitListExpr as a temporary.
`-CXXBindTemporaryExpr [...] 'struct Point' (CXXTemporary [...])
`-CompoundLiteralExpr [...] 'struct AggregateWithDtor'
`-InitListExpr [...] 'struct AggregateWithDtor'
|-IntegerLiteral [...] 'int' 1
`-IntegerLiteral [...] 'int' 2
llvm-svn: 181212
temporary to an lvalue before taking its address. This removes a weird special
case from the AST representation, and allows the constant expression evaluator
to deal with it without (broken) hacks.
llvm-svn: 180866
are now two distinct canonical 'AutoType's: one is the undeduced 'auto'
placeholder type, and the other is a deduced-but-dependent type. All
deduced-to-a-non-dependent-type cases are still non-canonical.
llvm-svn: 180789
When we find a friend declaration we have to skip transparent contexts for doing
lookups, but we should not skip them when inserting the new decl if the lookup
found nothing.
Fixes PR15841.
llvm-svn: 180571
statement in constexpr functions. Everything which doesn't require variable
mutation is also allowed as an extension in C++11. 'void' becomes a literal
type to support constexpr functions which return 'void'.
llvm-svn: 180022
C++1y, so stop adding the 'const' there. Provide a compatibility warning for
code relying on this in C++11, with a fix-it hint. Update our lazily-written
tests to add the const, except for those ones which were testing our
implementation of this rule.
llvm-svn: 179969
Still to do here:
- we have a collection of syntactic accepts-invalids to diagnose
- support non-PODs in VLAs, including dynamic initialization /
destruction
- runtime checks (and throw std::bad_array_length) for bad bound
- support VLA capture by reference in lambdas
- properly support VLAs in range-based for (don't recompute bound)
llvm-svn: 179962
Add a CXXDefaultInitExpr, analogous to CXXDefaultArgExpr, and use it both in
CXXCtorInitializers and in InitListExprs to represent a default initializer.
There's an additional complication here: because the default initializer can
refer to the initialized object via its 'this' pointer, we need to make sure
that 'this' points to the right thing within the evaluation.
llvm-svn: 179958
We currently emit an error message when you try to use thread local
storage on targets that don't support it and testing C++11 thread
locals will trip this. We don't want to xfail the test for all darwin
hosts so add a quick hack to check for darwin10 and disable the
test based on that. Only checking darwin10 because anything earlier
is really old and I don't have a list of what other hosts don't
support tls handy.
Alternate suggestions welcome!
llvm-svn: 179671
Add CapturedDecl to be the DeclContext for CapturedStmt, and perform semantic
analysis. Currently captures all variables by reference.
TODO: templates
Author: Ben Langmuir <ben.langmuir@intel.com>
Differential Revision: http://llvm-reviews.chandlerc.com/D433
llvm-svn: 179618