eliminating a bunch of redundant code and properly modeling how the
captures of outside blocks/lambdas affect the types seen by inner
captures.
This new scheme makes two passes over the capturing scope stack. The
first pass goes up the stack (from innermost to outermost), assessing
whether the capture looks feasible and stopping when it either hits
the scope where the variable is declared or when it finds an existing
capture. The second pass then walks down the stack (from outermost to
innermost), capturing the variable at each step and updating the
captured type and the type that an expression referring to that
captured variable would see. It also checks type-specific
restrictions, such as the inability to capture an array within a
block. Note that only the first odr-use of each
variable needs to do the full walk; subsequent uses will find the
capture immediately, so multiple walks need not occur.
The same routine that builds the captures can also compute the type of
the captures without signaling errors and without actually performing
the capture. This functionality is used to determine the type of
declaration references as well as implementing the weird decltype((x))
rule within lambda expressions.
The capture code now explicitly takes sides in the debate over C++
core issue 1249, which concerns the type of captures within nested
lambdas. We opt to use the more permissive, more useful definition
implemented by GCC rather than the one implemented by EDG.
llvm-svn: 150875
We had two separate issues here: firstly, varions functions were assuming that
they did not need to perform semantic checks on trivial destructors (this is
not true in C++11, where a trivial destructor can nonetheless be private or
deleted), and a bunch of DiagnoseUseOfDecl calls were missing for uses of
destructors.
llvm-svn: 150866
Holding the constructor directly makes no sense when list-initialized arrays come into play. The constructor is now held in a CXXConstructExpr, if construction is what is done. The new design can also distinguish properly between list-initialization and direct-initialization, as well as implicit default-initialization constructors and explicit value-initialization constructors. Finally, doing it this way removes redundance from the AST because CXXNewExpr doesn't try to handle both the allocation and the initialization responsibilities.
This breaks the static analysis of new expressions. I've filed PR12014 to track this.
llvm-svn: 150682
default is '=', and reword the warning about explicitly capturing
'this' in such lambdas to indicate that only explicit capture is
banned.
Introduce Fix-Its for this and other "save the programmer from
themself" rules regarding what can be explicitly captured and what
must be implicitly captured.
llvm-svn: 150256
- Capturing variables by-reference and by-copy within a lambda
- The representation of lambda captures
- The creation of the non-static data members in the lambda class
that store the captured variables
- The initialization of the non-static data members from the
captured variables
- Pretty-printing lambda expressions
There are a number of FIXMEs, both explicit and implied, including:
- Creating a field for a capture of 'this'
- Improved diagnostics for initialization failures when capturing
variables by copy
- Dealing with temporaries created during said initialization
- Template instantiation
- AST (de-)serialization
- Binding and returning the lambda expression; turning it into a
proper temporary
- Lots and lots of semantic constraints
- Parameter pack captures
llvm-svn: 149977
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
array new expression. This lays some groundwork for the implicit conversion to
integral or unscoped enumeration which C++11 ICEs undergo.
llvm-svn: 149772
new, is well-formed with defined semantics of throwing (a type which can be
caught by a handler for) std::bad_array_new_length, unlike in C++98 where it is
somewhere nebulous between undefined behavior and ill-formed.
If the array size is an integral constant expression and satisfies one of these
criteria, we would previous the array new expression, but now in C++11 mode, we
merely issue a warning (the code is still rejected in C++98 mode, naturally).
We don't yet implement new C++11 semantics correctly (see PR11644), but we do
implement the overflow checking, and (for the default operator new) convert such
expressions to an exception, so accepting such code now does not seem especially
unsafe.
llvm-svn: 149767
want to provide "po"-like functionality which
treats the result of an expression implicitly as
"id" (if it is not otherwise known) and prints
it as an Objective-C object.
This has in the past been gated by the
"DebuggerSupport" language option, but that is
too general. Debuggers also provide other commands
like "print" that do not make any assumptions
about whether the object is an Objective-C object.
This patch makes the assumption conditional on a
new language option: DebuggerCastResultToId. I
have also made corresponding modifications to the
testsuite.
llvm-svn: 149735
cleans up and improves a few things:
- We get rid of the ugly dance of computing all of the captures in
data structures that clone those of CapturingScopeInfo, centralizing
the logic for accessing/updating these data structures
- We re-use the existing capture logic for 'this', which actually
works now.
Cleaned up some diagnostic wording in minor ways as well.
llvm-svn: 149516
- Actually building the var -> capture mapping properly (there was an off-by-one error)
- Keeping track of the source location of each capture
- Minor QoI improvements, e.g, highlighing the prior capture if
there are multiple captures, pointing at the variable declaration we
found if we reject it.
As part of this, add standard citations for the various semantic
checks we perform, and note where we're not performing those checks as
we should.
llvm-svn: 149462
Fix some review comments.
Add a test for deduction when std::initializer_list isn't available yet.
Fix redundant error messages. This fixes and outstanding FIXME too.
llvm-svn: 148735
No new unit tests yet as there is no behavioral change
(except for slightly more specific filtering in
Sema::ActOnStartOfLambdaDefinition). Tests will be added
as the code paths are traced in greater depth to determine
how to improve the results--there are at least one or two
known bugs that require those improvements. This commit
lays the groundwork for those changes.
llvm-svn: 148382
expression for an Objective-C object or pointer type, so that we don't
attempt to treat the member name as a template. Fixes
<rdar://problem/10672501>.
llvm-svn: 148028
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
Microsoft __if_exists/__if_not_exists statement. Also note that we
weren't traversing DeclarationNameInfo *at all* within the
RecursiveASTVisitor, which would be rather fatal for variadic
templates.
llvm-svn: 142906
statements. As noted in the documentation for the AST node, the
semantics of __if_exists/__if_not_exists are somewhat different from
the way Visual C++ implements them, because our parsed-template
representation can't accommodate VC++ semantics without serious
contortions. Hopefully this implementation is "good enough".
llvm-svn: 142901
analysis to separate dependent names from non-dependent names. For
dependent names, we'll behave differently from Visual C++:
- For __if_exists/__if_not_exists at class scope, we'll just warn
and then ignore them.
- For __if_exists/__if_not_exists in statements, we'll treat the
inner statement as a compound statement, which we only instantiate
in templates where the dependent name (after instantiation)
exists. This behavior is different from VC++, but it's as close as
we can get without encroaching ridiculousness.
The latter part (dependent statements) is not yet implemented.
llvm-svn: 142864
and DefaultFunctionArrayLvalueConversion. To prevent
significant regression for should-this-be-a-call fixits,
and to repair some such regression from the introduction of
bound member placeholders, make those placeholder checks
try to build calls appropriately. Harden the build-a-call
logic while we're at it.
llvm-svn: 141738
C-style and functional casts are built in SemaCXXCast.cpp.
Introduce a helper class to encapsulate most of the random
state being passed around, at least one level down.
llvm-svn: 141170
is cast to a boolean. An exception has been made for string literals in
logical expressions to allow the common case of use in assert statements.
bool x;
x = "hi"; // Warn here
void foo(bool x);
foo("hi"); // Warn here
assert(0 && "error");
assert("error); // Warn here
llvm-svn: 140405
the lifetime of the block by copying it to the heap, or else we'll get
a dangling reference because the code working with the non-block-typed
object will not know it needs to copy.
There is some danger here, e.g. with assigning a block literal to an
unsafe variable, but, well, it's an unsafe variable.
llvm-svn: 139451
builtin types (When requested). This is another step toward making
ASTUnit build the ASTContext as needed when loading an AST file,
rather than doing so after the fact. No actual functionality change (yet).
llvm-svn: 138985
case situations with the unary operators & and *. Also extend the array bounds
checking to work with pointer arithmetic; the pointer arithemtic checking can
be turned on using -Warray-bounds-pointer-arithmetic.
The changes to where CheckArrayAccess gets called is based on some trial &
error and a bunch of digging through source code and gdb backtraces in order
to have the check performed under as many situations as possible (such as for
variable initializers, arguments to function calls, and within conditional in
addition to the simpler cases of the operands to binary and unary operator)
while not being called--and triggering warnings--more than once for a given
ArraySubscriptExpr.
llvm-svn: 136997
1. Attempting to delete an expression of incomplete class type should be an error, not a warning.
2. If someone tries to delete a pointer to an incomplete class type, make sure we actually emit
the delete expression after we warn.
llvm-svn: 136161
where we have an immediate need of a retained value.
As an exception, don't do this when the call is made as the immediate
operand of a __bridge retain. This is more in the way of a workaround
than an actual guarantee, so it's acceptable to be brittle here.
rdar://problem/9504800
llvm-svn: 134605
throw-expressions, such that we don't consider the NRVO when the
non-volatile automatic object comes from outside the innermost try
scope (C++0x [class.copymove]p13). In C++98/03, our ASTs were
incorrect but it didn't matter because IR generation doesn't actually
apply the NRVO here. In C++0x, however, we were moving from an object
when in fact we should have copied from it. Fixes PR10142 /
<rdar://problem/9714312>.
llvm-svn: 134548
Language-design credit goes to a lot of people, but I particularly want
to single out Blaine Garst and Patrick Beard for their contributions.
Compiler implementation credit goes to Argyrios, Doug, Fariborz, and myself,
in no particular order.
llvm-svn: 133103
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
Allow to include or exclude code depending on if a symbol exists or not. Just like a #ifdef but for C/C++ symbols.
More doc: http://msdn.microsoft.com/en-us/library/x7wy9xh3(v=VS.100).aspx
Support at class and namespace scopes will be added later.
llvm-svn: 131014
instead of 'int'.
The Embarcadero spec says 'unsigned int', not 'int'. That's what
'size_t' is on Windows, but for Clang using a 'size_t' that can be
larger than int seems more appropriate.
llvm-svn: 130653
functions already precluded dependent types from reaching them.
Also change one of the callers to not error when a trait is applied to
a dependent type. This is a perfectly reasonable pattern, and both Unary
and Binary type traits already support dependent types (by populating
the AST with a nonce value).
Remove the actual diagnostic, since these aren't errors.
llvm-svn: 130651
a switch with any default case. This both warns when an enumerator is
missing and asserts if a value sneaks through despite the warning.
While in there fix a bunch of coding style issues with this code.
llvm-svn: 130648
As might be surmised from their names, these aren't type traits, they're
expression traits. Amazingly enough, they're expression traits that we
have, and fully implement. These "type" traits are even parsed from the
same tokens as the expression traits. Luckily, the parser only tried the
expression trait parsing for these tokens, so this was all just a pile
of dead code.
llvm-svn: 130643
1) Moved the completeness checking routine above the evaluation routine
so the reader sees that we do in fact check for complete types when
necessary.
2) Remove the FIXME comment about not doing this.
3) Make the arguments to the evaluate function agree in order with those
to the completeness checking function.
4) Completely specify the enumerators for the completeness checking
function rather than relying on a default.
5) Remove a check for the Borland language to only require complete
types in a few places. Borland's own documentation doesn't agree with
this: some of the previously unspecified traits *do* require
a complete type, some don't.
6) Correctly split the traits which do not require complete types from
those that do, clarifying comments and citations to the standard or
other documentation where relevant.
llvm-svn: 130641
trait arguments. Reflow the logic to use early exit instead of a complex
condition expression. Switch to a switch for acting on different type
traits and add a bunch of the recently implemented type traits here.
This fixes one of the regressions with the new __is_standard_layout
trait to again require a complete type. It also fixes some latent bugs
in other traits that never did impose this despite the standard
requiring it. However, all these bugs were hidden for non-borland
systems where the default is to require a complete type.
It's unclear to me what the best approach here is: providing an explicit
lists for the ones requiring complete types only w/ Borland and using
a default for the rest, or forcing this switch to enumerate the traits
and make it clear which way each one goes.
I'm still working on cleaning up the tests so that they actually catch
this, a much more comprehensive update to the tests will come once I've
worked through the bugs I'm finding via inspection.
llvm-svn: 130604
a Type method isStandardLayoutType, to keep our user API matching the
type trait builtins as closely as possible. Also, implement it in terms
of other Type APIs rather than in terms of other type traits. This
models the implementation on that of isLiteralType and isTrivialType.
There remain some common problems with these traits still, so this is
a bit of a WIP. However, we can now fix all of these traits at the same
time and in a consistent manner.
llvm-svn: 130602
type trait. The previous implementation suffered from several problems:
1) It implemented all of the logic in RecordType by walking over every
base and field in a CXXRecordDecl and validating the constraints of
the standard. This made for very straightforward code, but is
extremely inefficient. It also is conceptually wrong, the logic tied
to the C++ definition of standard-layout classes should be in
CXXRecordDecl, not RecordType.
2) To address the performance problems with #1, a cache bit was added to
CXXRecordDecl, and at the completion of every C++ class, the
RecordType was queried to determine if it was a standard layout
class, and that state was cached. Two things went very very wrong
with this. First, the caching version of the query *was never
called*. Even within the recursive steps of the walk over all fields
and bases the caching variant was not called, making each query
a full *recursive* walk. Second, despite the cache not being used, it
was computed for every class declared, even when the trait was never
used in the program. This probably significantly regressed compile
time performance for edge-case files.
3) An ASTContext was required merely to query the type trait because
querying it performed the actual computations.
4) The caching bit wasn't managed correctly (uninitialized).
The new implementation follows the system for all the other traits on
C++ classes by encoding all the state needed in the definition data and
building up the trait incrementally as each base and member are added to
the definition of the class.
The idiosyncracies of the specification of standard-layout classes
requires more state than I would like; currently 5 bits. I could
eliminate one of the bits easily at the expense of both clarity and
resilience of the code. I might be able to eliminate one of the other
bits by computing its state in terms of other state bits in the
definition. I've already done that in one place where there was a fairly
simple way to achieve it.
It's possible some of the bits could be moved out of the definition data
and into some other structure which isn't serialized if the serialized
bloat is a problem. That would preclude serialization of a partial class
declaration, but that's likely already precluded.
Comments on any of these issues welcome.
llvm-svn: 130601
Patch authored by John Wiegley.
These are array type traits used for parsing code that employs certain
features of the Embarcadero C++ compiler: __array_rank(T) and
__array_extent(T, Dim).
llvm-svn: 130351
Patch authored by John Wiegley.
These type traits are used for parsing code that employs certain features of
the Embarcadero C++ compiler. Several of these constructs are also desired by
libc++, according to its project pages (such as __is_standard_layout).
llvm-svn: 130342
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
Patch authored by David Abrahams.
These two expression traits (__is_lvalue_expr, __is_rvalue_expr) are used for
parsing code that employs certain features of the Embarcadero C++ compiler.
llvm-svn: 130122
This introduces a few APIs on the AST to bundle up the standard-based
logic so that programmatic clients have access to exactly the same
behavior.
There is only one serious FIXME here: checking for non-trivial move
constructors and move assignment operators. Those bits need to be added
to the declaration and accessors provided.
This implementation should be enough for the uses of __is_trivial in
libstdc++ 4.6's C++98 library implementation.
Ideas for more thorough test cases or any edge cases missing would be
appreciated. =D
llvm-svn: 130057
Sebastian Redl