Summary:
When thread safety annotations are used without capability arguments,
they are assumed to apply to `this` instead. So we warn when either
`this` doesn't exist, or the class is not a capability type.
This is based on earlier work by Josh Gao that was committed in r310403,
but reverted in r310698 because it didn't properly work in template
classes. See also D36237.
The solution is not to go via the QualType of `this`, which is then a
template type, hence the attributes are not known because it could be
specialized. Instead we look directly at the class in which we are
contained.
Additionally I grouped two of the warnings together. There are two
issues here: the existence of `this`, which requires us to be a
non-static member function, and the appropriate annotation on the class
we are contained in. So we don't distinguish between not being in a
class and being static, because in both cases we don't have `this`.
Fixes PR38399.
Reviewers: aaron.ballman, delesley, jmgao, rtrieu
Reviewed By: delesley
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D51901
llvm-svn: 342605
For function pointers, the FunctionDecl of the callee is unknown, so
getDirectCallee will return nullptr. We have to catch that case to avoid
crashing. We assume there is no attribute then.
llvm-svn: 342519
Summary:
We run the tests for -Wthread-safety-{negative,verbose} with the new
attributes as well as the old ones. Also put the macros in a header so
that we don't have to copy them all around.
The warn-thread-safety-parsing.cpp test checks for warnings depending on
the actual attribute name, so it can't undergo the same treatment.
Together with D49275 this should fix PR33754.
Reviewers: aaron.ballman, delesley, grooverdan
Reviewed By: aaron.ballman
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D52141
llvm-svn: 342418
Summary:
Attributes on member classes of class templates and member class templates
of class templates are not currently instantiated. This was discovered by
Richard Smith here:
http://lists.llvm.org/pipermail/cfe-dev/2018-September/059291.html
This commit makes sure that attributes are instantiated properly. This
commit does not fix the broken behavior for member partial and explicit
specializations of class templates.
PR38913
Reviewers: rsmith
Subscribers: dexonsmith, cfe-commits
Differential Revision: https://reviews.llvm.org/D51997
llvm-svn: 342238
A lambda's closure is initialized when the lambda is declared. For
implicit captures, the initialization code emitted from EmitLambdaExpr
references source locations *within the lambda body* in the function
containing the lambda. This results in a poor debugging experience: we
step to the line containing the lambda, then into lambda, out again,
over and over, until every capture's field is initialized.
To improve stepping behavior, assign the starting location of the lambda
to expressions which initialize an implicit capture within it.
rdar://39807527
Differential Revision: https://reviews.llvm.org/D50927
llvm-svn: 342194
Problem was that we were appending to the source location info buffer in the
copy assignment operator (instead of overwriting).
rdar://42746401
llvm-svn: 341869
match when checking for redeclaration of a function template.
This properly handles differences in deduced return types, particularly
when performing redeclaration checks for a friend function template.
llvm-svn: 341778
accessible from the context where aggregate initialization occurs.
rdar://problem/38168772
Differential Revision: https://reviews.llvm.org/D45898
llvm-svn: 341629
destructors.
We previously tried to patch up the exception specification after
completing the class, which went wrong when the exception specification
was needed within the class body (in particular, by a friend
redeclaration of the destructor in a nested class). We now mark the
destructor as having a not-yet-computed exception specification
immediately after creating it.
This requires delaying various checks against the exception
specification (where we'd previously have just got the wrong exception
specification, and now find we have an exception specification that we
can't compute yet) when those checks fire while the class is being
defined.
This also exposed an issue that we were missing a CodeSynthesisContext
for computation of exception specifications (otherwise we'd fail to make
the module containing the definition of the class visible when computing
its members' exception specs). Adding that incidentally also gives us a
diagnostic quality improvement.
This has also exposed an pre-existing problem: making the exception
specification evaluation context a non-SFINAE context (as it should be)
results in a bootstrap failure; PR38850 filed for this.
llvm-svn: 341499
Summary:
It's already allowed to prematurely release a scoped lock, now we also
allow relocking it again, possibly even in another mode.
This is the second attempt, the first had been merged as r339456 and
reverted in r339558 because it caused a crash.
Reviewers: delesley, aaron.ballman
Reviewed By: delesley, aaron.ballman
Subscribers: hokein, cfe-commits
Differential Revision: https://reviews.llvm.org/D49885
llvm-svn: 340459
This commit adds the flag -fno-c++-static-destructors and the attributes
[[clang::no_destroy]] and [[clang::always_destroy]]. no_destroy specifies that a
specific static or thread duration variable shouldn't have it's destructor
registered, and is the default in -fno-c++-static-destructors mode.
always_destroy is the opposite, and is the default in -fc++-static-destructors
mode.
A variable whose destructor is disabled (either because of
-fno-c++-static-destructors or [[clang::no_destroy]]) doesn't count as a use of
the destructor, so we don't do any access checking or mark it referenced. We
also don't emit -Wexit-time-destructors for these variables.
rdar://21734598
Differential revision: https://reviews.llvm.org/D50994
llvm-svn: 340306
Specifically, AttributedType now tracks a regular attr::Kind rather than
having its own parallel Kind enumeration, and AttributedTypeLoc now
holds an Attr* instead of holding an ad-hoc collection of Attr fields.
Differential Revision: https://reviews.llvm.org/D50526
This reinstates r339623, reverted in r339638, with a fix to not fail
template instantiation if we instantiate a QualType with no associated
type source information and we encounter an AttributedType.
llvm-svn: 340215
Summary:
This is for use by clang-tidy's bugprone-use-after-move check -- see
corresponding clang-tidy patch at https://reviews.llvm.org/D49910.
Reviewers: aaron.ballman, rsmith
Reviewed By: aaron.ballman
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D49911
llvm-svn: 339569
__builtin_memmove (in non-type-punning cases).
This is intended to permit libc++ to make std::copy etc constexpr
without sacrificing the optimization that uses memcpy on
trivially-copyable types.
__builtin_strcpy and __builtin_wcscpy are not handled by this change.
They'd be straightforward to add, but we haven't encountered a need for
them just yet.
This reinstates r338455, reverted in r338602, with a fix to avoid trying
to constant-evaluate a memcpy call if either pointer operand has an
invalid designator.
llvm-svn: 338941
Recommit of r335084 after revert in r335516.
... instead of prepending it at the beginning (the original behavior
since implemented in r122535 2010-12-23). This builds up an
AttributeList in the the order in which the attributes appear in the
source.
The reverse order caused nodes for attributes in the AST (e.g. LoopHint)
to be in the reverse order, and therefore printed in the wrong order in
-ast-dump. Some TODO comments mention this. The order was explicitly
reversed for enable_if attribute overload resolution and name mangling,
which is not necessary anymore with this patch.
The change unfortunately has some secondary effect, especially on
diagnostic output. In the simplest cases, the CHECK lines or expected
diagnostic were changed to the the new output. If the kind of
error/warning changed, the attributes' order was changed instead.
This unfortunately causes some 'previous occurrence here' hints to be
textually after the main marker. This typically happens when attributes
are merged, but are incompatible to each other. Interchanging the role
of the the main and note SourceLocation will also cause the case where
two different declaration's attributes (in contrast to multiple
attributes of the same declaration) are merged to be reverse. There is
no easy fix because sometimes previous attributes are merged into a new
declaration's attribute list, sometimes new attributes are added to a
previous declaration's attribute list. Since 'previous occurrence here'
pointing to locations after the main marker is not rare, I left the
markers as-is; it is only relevant when the attributes are declared in
the same declaration anyway.
Differential Revision: https://reviews.llvm.org/D48100
llvm-svn: 338800
It caused asserts during Chromium builds, see reply on the cfe-commits thread.
> This is intended to permit libc++ to make std::copy etc constexpr
> without sacrificing the optimization that uses memcpy on
> trivially-copyable types.
>
> __builtin_strcpy and __builtin_wcscpy are not handled by this change.
> They'd be straightforward to add, but we haven't encountered a need for
> them just yet.
llvm-svn: 338602
This patch adds support for a new attribute, [[clang::lifetimebound]], that
indicates that the lifetime of a function result is related to one of the
function arguments. When walking an initializer to make sure that the lifetime
of the initial value is at least as long as the lifetime of the initialized
object, we step through parameters (including the implicit object parameter of
a non-static member function) that are marked with this attribute.
There's nowhere to write an attribute on the implicit object parameter, so in
lieu of that, it may be applied to a function type (where it appears
immediately after the cv-qualifiers and ref-qualifier, which is as close to a
declaration of the implicit object parameter as we have). I'm currently
modeling this in the AST as the attribute appertaining to the function type.
Differential Revision: https://reviews.llvm.org/D49922
llvm-svn: 338464
__builtin_memmove (in non-type-punning cases).
This is intended to permit libc++ to make std::copy etc constexpr
without sacrificing the optimization that uses memcpy on
trivially-copyable types.
__builtin_strcpy and __builtin_wcscpy are not handled by this change.
They'd be straightforward to add, but we haven't encountered a need for
them just yet.
llvm-svn: 338455
Previously, we just canonicalized the type, but this lead to crashes with
parameter types that referred to ParmVarDecls of the constructor. There may be
more cases that this TreeTransform needs to handle though, such as a constructor
parameter type referring to a member in an unevaluated context. Canonicalization
doesn't address these cases either though, so we can address them as-needed in
follow-up commits.
rdar://41330135
Differential revision: https://reviews.llvm.org/D49439
llvm-svn: 338165
Check each case value in turn while parsing it, performing the
conversion to the switch type within the context of the expression
itself. This will become necessary in order to properly handle cleanups
for temporaries created as part of the case label (in an upcoming
patch). For now it's just good hygiene.
This necessitates moving the checking for the switch condition itself to
earlier, so that the destination type is available when checking the
case labels.
As a nice side-effect, we get slightly improved diagnostic quality and
error recovery by separating the case expression checking from the case
statement checking and from tracking whether there are discarded case
labels.
llvm-svn: 338056
Summary:
As discussed in [[ https://bugs.llvm.org/show_bug.cgi?id=38166 | PR38166 ]], we need to be able to distinqush whether the cast
we are visiting is actually a cast, or part of an `ExplicitCast`.
There are at least four ways to get there:
1. Introduce a new `CastKind`, and use it instead of `IntegralCast` if we are in `ExplicitCast`.
Would work, but does not scale - what if we will need more of these cast kinds?
2. Introduce a flag in `CastExprBits`, whether this cast is part of `ExplicitCast` or not.
Would work, but it isn't immediately clear where it needs to be set.
2. Fix `ScalarExprEmitter::VisitCastExpr()` to visit these `NoOp` casts.
As pointed out by @rsmith, CodeGenFunction::EmitMaterializeTemporaryExpr calls
skipRValueSubobjectAdjustments, which steps over the CK_NoOp cast`,
which explains why we currently don't visit those.
This is probably impossible, as @efriedma points out, that is intentional as per `[class.temporary]` in the standard
3. And the simplest one, just record which NoOp casts we skip.
It just kinda works as-is afterwards.
But, the approach with a flag is the least intrusive one, and is probably the best one overall.
Reviewers: rsmith, rjmccall, majnemer, efriedma
Reviewed By: rsmith
Subscribers: cfe-commits, aaron.ballman, vsk, llvm-commits, rsmith
Differential Revision: https://reviews.llvm.org/D49508
llvm-svn: 337815
Clang would crash when instantiating a BlockDecl that appeared in a
default-member-initializer of a class template. Fix this by deferring the
instantiation until we instantate the BlockExpr.
rdar://41200624
Differential revision: https://reviews.llvm.org/D49688
llvm-svn: 337766
This reinstates r337627, reverted in r337671, with a fix to correctly
handle the lvalueness of array subscript expressions on pointers.
llvm-svn: 337726
Discovered because of: https://bugs.llvm.org/show_bug.cgi?id=38235
It seems to me that a scoped enum should NOT be an integral constant expression
without a cast, so this seems like a sensical change.
Attributes that check for an integer parameter simply use this function to
ensure that they have an integer, so it was previously allowing a scoped enum.
Also added a test based on Richard's feedback to ensure that case labels still work.
Differential Revision: https://reviews.llvm.org/D49599
llvm-svn: 337585
As documented here: https://software.intel.com/en-us/node/682969 and
https://software.intel.com/en-us/node/523346. cpu_dispatch multiversioning
is an ICC feature that provides for function multiversioning.
This feature is implemented with two attributes: First, cpu_specific,
which specifies the individual function versions. Second, cpu_dispatch,
which specifies the location of the resolver function and the list of
resolvable functions.
This is valuable since it provides a mechanism where the resolver's TU
can be specified in one location, and the individual implementions
each in their own translation units.
The goal of this patch is to be source-compatible with ICC, so this
implementation diverges from the ICC implementation in a few ways:
1- Linux x86/64 only: This implementation uses ifuncs in order to
properly dispatch functions. This is is a valuable performance benefit
over the ICC implementation. A future patch will be provided to enable
this feature on Windows, but it will obviously more closely fit ICC's
implementation.
2- CPU Identification functions: ICC uses a set of custom functions to identify
the feature list of the host processor. This patch uses the cpu_supports
functionality in order to better align with 'target' multiversioning.
1- cpu_dispatch function def/decl: ICC's cpu_dispatch requires that the function
marked cpu_dispatch be an empty definition. This patch supports that as well,
however declarations are also permitted, since the linker will solve the
issue of multiple emissions.
Differential Revision: https://reviews.llvm.org/D47474
llvm-svn: 337552
Erik Pilkington