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
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
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
- References to ObjC bit-field ivars are bit-field lvalues;
fixes rdar://13794269, which got me started down this.
- Introduce Expr::refersToBitField, switch a couple users to
it where semantically important, and comment the difference
between this and the existing API.
- Discourage Expr::getBitField by making it a bit longer and
less general-sounding.
- Lock down on const_casts of bit-field gl-values until we
hear back from the committee as to whether they're allowed.
llvm-svn: 181252
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
to use. This makes very little difference right now (other than suppressing
follow-on errors in some cases), but will matter more once we support deduced
return types (we don't want expressions with undeduced return types in the
AST).
llvm-svn: 181107
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
For this source:
const int &ref = someStruct.bitfield;
We used to generate this AST:
DeclStmt [...]
`-VarDecl [...] ref 'const int &'
`-MaterializeTemporaryExpr [...] 'const int' lvalue
`-ImplicitCastExpr [...] 'const int' lvalue <NoOp>
`-MemberExpr [...] 'int' lvalue bitfield .bitfield [...]
`-DeclRefExpr [...] 'struct X' lvalue ParmVar [...] 'someStruct' 'struct X'
Notice the lvalue inside the MaterializeTemporaryExpr, which is very
confusing (and caused an assertion to fire in the analyzer - PR15694).
We now generate this:
DeclStmt [...]
`-VarDecl [...] ref 'const int &'
`-MaterializeTemporaryExpr [...] 'const int' lvalue
`-ImplicitCastExpr [...] 'int' <LValueToRValue>
`-MemberExpr [...] 'int' lvalue bitfield .bitfield [...]
`-DeclRefExpr [...] 'struct X' lvalue ParmVar [...] 'someStruct' 'struct X'
Which makes a lot more sense. This allows us to remove code in both
CodeGen and AST that hacked around this special case.
The commit also makes Clang accept this (legal) C++11 code:
int &&ref = std::move(someStruct).bitfield
PR15694 / <rdar://problem/13600396>
llvm-svn: 179250
The TypeLoc hierarchy used the llvm::cast machinery to perform undefined
behavior by casting pointers/references to TypeLoc objects to derived types
and then using the derived copy constructors (or even returning pointers to
derived types that actually point to the original TypeLoc object).
Some context is in this thread:
http://lists.cs.uiuc.edu/pipermail/llvmdev/2012-December/056804.html
Though it's spread over a few months which can be hard to read in the mail
archive.
llvm-svn: 175462
MarkMemberReferenced instead of marking functions referenced directly. An audit
of callers to MarkFunctionReferenced and DiagnoseUseOfDecl also caused a few
other changes:
* don't mark functions odr-used when considering them for an initialization
sequence. Do mark them referenced though.
* the function nominated by the cleanup attribute should be diagnosed.
* operator new/delete should be diagnosed when building a 'new' expression.
llvm-svn: 174951
resolving an overloaded function reference within an initializer list.
Previously we would try to resolve the overloaded function reference without
first stripping off the InitListExpr wrapper.
llvm-svn: 172517
Changed getLocStart() and getLocEnd() to be required for Stmts, and make
getSourceRange() optional. The default implementation for getSourceRange()
is build the range by calling getLocStart() and getLocEnd().
llvm-svn: 171067
copy-list-initialization (and doesn't add an additional copy step):
Fill in the ListInitialization bit when creating a CXXConstructExpr. Use it
when instantiating initializers in order to correctly handle instantiation of
copy-list-initialization. Teach TreeTransform that function arguments are
initializations, and so need this special treatment too. Finally, remove some
hacks which were working around SubstInitializer's shortcomings.
llvm-svn: 170489
This does limit these typedefs to being sequences, but no current usage
requires them to be contiguous (we could expand this to a more general
iterator pair range concept at some point).
Also, it'd be nice if SmallVector were constructible directly from an ArrayRef
but this is a bit tricky since ArrayRef depends on SmallVectorBaseImpl for the
inverse conversion. (& generalizing over all range-like things, while nice,
would require some nontrivial SFINAE I haven't thought about yet)
llvm-svn: 170482
properly, rather than faking it up by pretending that a reference member makes
the default constructor non-trivial. That leads to rejects-valids when putting
such types inside unions.
llvm-svn: 169662
uncovered.
This required manually correcting all of the incorrect main-module
headers I could find, and running the new llvm/utils/sort_includes.py
script over the files.
I also manually added quite a few missing headers that were uncovered by
shuffling the order or moving headers up to be main-module-headers.
llvm-svn: 169237
objc_loadWeak. This retains and autorelease the weakly-refereced
object. This hidden autorelease sometimes makes __weak variable alive even
after the weak reference is erased, because the object is still referenced
by an autorelease pool. This patch overcomes this behavior by loading a
weak object via call to objc_loadWeakRetained(), followng it by objc_release
at appropriate place, thereby removing the hidden autorelease. // rdar://10849570
llvm-svn: 168740
new container so we can safely iterate over them.
The container holding the lookup decls can under certain conditions
be changed while iterating (e.g. because of deserialization).
llvm-svn: 167816
Within the body of the loop the underlying map may be modified via
Sema::AddOverloadCandidate
-> Sema::CompareReferenceRelationship
-> Sema::RequireCompleteType
to avoid the use of invalid iterators the sequence is copied first.
A reliable, though large, test case is available - it will be reduced and
committed shortly.
Patch by Robert Muth. Review by myself, Nico Weber, and Rafael Espindola.
llvm-svn: 166188
-Allow Sema to do more processing on the initial Expr before checking it.
-Remove the special conditions in HandleExpr()
-Move the code so that only one call site is needed.
-Removed the function from Sema and only call it locally.
-Warn on potentially evaluated reference variables, not just casts to r-values.
-Update tests.
llvm-svn: 164951
actually perform value initialization rather than trying to fake it with a call
to the default constructor. Fixes various bugs related to the previously-missing
zero-initialization in this case.
I've also moved this and the other list initialization 'special case' from
TryConstructorInitialization into TryListInitialization where they belong.
llvm-svn: 159733
* Escape #, < and @ symbols where Doxygen would try to interpret them;
* Fix several function param documentation where names had got out of sync;
* Delete param documentation referring to parameters that no longer exist.
llvm-svn: 158472
In addition, I've made the pointer and reference typedef 'void' rather than T*
just so they can't get misused. I would've omitted them entirely but
std::distance likes them to be there even if it doesn't use them.
This rolls back r155808 and r155869.
Review by Doug Gregor incorporating feedback from Chandler Carruth.
llvm-svn: 158104
temporary or an array subobject of a class temporary, and the resulting value
is used to initialize a pointer which outlives the temporary. Such a pointer
is always left dangling after the initialization completes and the array's
lifetime ends.
In order to detect this situation, this change also adds an
LValueClassification of LV_ArrayTemporary for temporaries of array type which
aren't subobjects of class temporaries. These occur in C++11 T{...} and GNU C++
(T){...} expressions, when T is an array type. Previously we treated the former
as a generic prvalue and the latter as a class temporary.
llvm-svn: 157955
in-class initializer for one of its fields. Value-initialization of such
a type should use the in-class initializer!
The former was just a bug, the latter is a (reported) standard defect.
llvm-svn: 156274
off PartialDiagnostic. PartialDiagnostic is rather heavyweight for
something that is in the critical path and is rarely used. So, switch
over to an abstract-class-based callback mechanism that delays most of
the work until a diagnostic is actually produced. Good for ~11k code
size reduction in the compiler and 1% speedup in -fsyntax-only on the
code in <rdar://problem/11004361>.
llvm-svn: 156176
filter_decl_iterator had a weird mismatch where both op* and op-> returned T*
making it difficult to generalize this filtering behavior into a reusable
library of any kind.
This change errs on the side of value, making op-> return T* and op* return
T&.
(reviewed by Richard Smith)
llvm-svn: 155808
- The [class.protected] restriction is non-trivial for any instance
member, even if the access lacks an object (for example, if it's
a pointer-to-member constant). In this case, it is equivalent to
requiring the naming class to equal the context class.
- The [class.protected] restriction applies to accesses to constructors
and destructors. A protected constructor or destructor can only be
used to create or destroy a base subobject, as a direct result.
- Several places were dropping or misapplying object information.
The standard could really be much clearer about what the object type is
supposed to be in some of these accesses. Usually it's easy enough to
find a reasonable answer, but still, the standard makes a very confident
statement about accesses to instance members only being possible in
either pointer-to-member literals or member access expressions, which
just completely ignores concepts like constructor and destructor
calls, using declarations, unevaluated field references, etc.
llvm-svn: 154248
track whether the referenced declaration comes from an enclosing
local context. I'm amenable to suggestions about the exact meaning
of this bit.
llvm-svn: 152491
- getSourceRange().getBegin() is about as awesome a pattern as .copy().size().
I already killed the hot paths so this doesn't seem to impact performance on my
tests-of-the-day, but it is a much more sensible (and shorter) pattern.
llvm-svn: 152419
explicit conversion functions to initialize the argument to a
copy/move constructor that itself is the subject of direct
initialization. Since we don't have that much context in overload
resolution, we end up threading more flags :(.
Fixes <rdar://problem/10903741> / PR10456.
llvm-svn: 151409
We now generate temporary arrays to back std::initializer_list objects
initialized with braces. The initializer_list is then made to point at
the array. We support both ptr+size and start+end forms, although
the latter is untested.
Array lifetime is correct for temporary std::initializer_lists (e.g.
call arguments) and local variables. It is untested for new expressions
and member initializers.
Things left to do:
Massively increase the amount of testing. I need to write tests for
start+end init lists, temporary objects created as a side effect of
initializing init list objects, new expressions, member initialization,
creation of temporary objects (e.g. std::vector) for initializer lists,
and probably more.
Get lifetime "right" for member initializers and new expressions. Not
that either are very useful.
Implement list-initialization of array new expressions.
llvm-svn: 150803
function, provide a specialized diagnostic that indicates the kind of
special member function (default constructor, copy assignment
operator, etc.) and that it was implicitly deleted. Add a hook where
we can provide more detailed information later.
llvm-svn: 150611
used to construct an object of union type with a deleted default constructor
(plus fixes for some related value-initialization corner cases).
llvm-svn: 150502
instead of having a special-purpose function.
- ActOnCXXDirectInitializer, which was mostly duplication of
AddInitializerToDecl (leading e.g. to PR10620, which Eli fixed a few days
ago), is dropped completely.
- MultiInitializer, which was an ugly hack I added, is dropped again.
- We now have the infrastructure in place to distinguish between
int x = {1};
int x({1});
int x{1};
-- VarDecl now has getInitStyle(), which indicates which of the above was used.
-- CXXConstructExpr now has a flag to indicate that it represents list-
initialization, although this is not yet used.
- InstantiateInitializer was renamed to SubstInitializer and simplified.
- ActOnParenOrParenListExpr has been replaced by ActOnParenListExpr, which
always produces a ParenListExpr. Placed that so far failed to convert that
back to a ParenExpr containing comma operators have been fixed. I'm pretty
sure I could have made a crashing test case before this.
The end result is a (I hope) considerably cleaner design of initializers.
More importantly, the fact that I can now distinguish between the various
initialization kinds means that I can get the tricky generalized initializer
test cases Johannes Schaub supplied to work. (This is not yet done.)
This commit passed self-host, with the resulting compiler passing the tests. I
hope it doesn't break more complicated code. It's a pretty big change, but one
that I feel is necessary.
llvm-svn: 150318
cv-unqualified type. This is essential in order to allow move-only objects of
const-qualified types to be copy-initialized via a converting constructor.
llvm-svn: 150309
value of class type, look for a unique conversion operator converting to
integral or unscoped enumeration type and use that. Implements [expr.const]p5.
Sema::VerifyIntegerConstantExpression now performs the conversion and returns
the converted result. Some important callers of Expr::isIntegralConstantExpr
have been switched over to using it (including all of those required for C++11
conformance); this switch brings a side-benefit of improved diagnostics and, in
several cases, simpler code. However, some language extensions and attributes
have not been moved across and will not perform implicit conversions on
constant expressions of literal class type where an ICE is required.
In passing, fix static_assert to perform a contextual conversion to bool on its
argument.
llvm-svn: 149776
to an error, so that users can turn them off if necessary. Note that
this does *not* change the behavior of in a SFINAE context, where we
still flag an error even if the warning is disabled. This matches
GCC's behavior.
llvm-svn: 148701
values and non-type template arguments of integral and enumeration types.
This change causes some legal C++98 code to no longer compile in C++11 mode, by
enforcing the C++11 rule that narrowing integral conversions are not permitted
in the final implicit conversion sequence for the above cases.
llvm-svn: 148439
for it to be used in converted constant expression checking, and fix a couple
of issues:
- Conversion operators implicitly invoked prior to the narrowing conversion
were not being correctly handled when determining whether a constant value
was narrowed.
- For conversions from floating-point to integral types, the diagnostic text
incorrectly always claimed that the source expression was not a constant
expression.
llvm-svn: 148381
fails within a call to a constexpr function. Add -fconstexpr-backtrace-limit
argument to driver and frontend, to control the maximum number of notes so
produced (default 10). Fix APValue printing to be able to pretty-print all
APValue types, and move the testing for this functionality from a unittest to
a -verify test now that it's visible in clang's output.
llvm-svn: 146749
This supports single-element initializer lists for references according to DR1288, as well as creating temporaries and binding to them for other initializer lists.
llvm-svn: 145186
pointer mismatch. Cases covered are: initialization, assignment, and function
arguments. Additional text will give the extra information about the nature
of the mismatch: different classes for member functions, wrong number of
parameters, different parameter type, different return type, and function
qualifier mismatch.
llvm-svn: 145114
implicitly perform an lvalue-to-rvalue conversion if used on an lvalue
expression. Also improve the documentation of Expr::Evaluate* to indicate which
of them will accept expressions with side-effects.
llvm-svn: 143263
expressions: expressions which refer to a logical rather
than a physical l-value, where the logical object is
actually accessed via custom getter/setter code.
A subsequent patch will generalize the AST for these
so that arbitrary "implementing" sub-expressions can
be provided.
Right now the only client is ObjC properties, but
this should be generalizable to similar language
features, e.g. Managed C++'s __property methods.
llvm-svn: 142914
This also applies to C99-style aggregate literals, should they be used in C++11, since they are effectively identical to constructor call list-initialization syntax.
llvm-svn: 142147
- Remodel Expr::EvaluateAsInt to behave like the other EvaluateAs* functions,
and add Expr::EvaluateKnownConstInt to capture the current fold-or-assert
behaviour.
- Factor out evaluation of bitfield bit widths.
- Fix a few places which would evaluate an expression twice: once to determine
whether it is a constant expression, then again to get the value.
llvm-svn: 141561
(No testcase because I don't think we have any way to actually write a testcase for this; the chosen value of NumElements has no effects on anything other than performance and memory usage.)
llvm-svn: 141106
Richard Smith