4664 Commits

Author SHA1 Message Date
Erik Pilkington
c587164422 [AST] Fix a crash on invalid.
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
2018-09-10 21:54:04 +00:00
Richard Smith
8eeb16f5d1 Enhance -Wc++14-compat for class template argument deduction to list the
deduced type (if known).

llvm-svn: 341858
2018-09-10 20:31:03 +00:00
Erich Keane
659c871a1b Prevent cpu-specific/cpu-dispatch from giong on a lambda.
It is non-sensical to use cpu-specific/cpu-dispatch multiversioning
on a lambda, so prevent it when trying to add the attribute.

llvm-svn: 341833
2018-09-10 14:31:56 +00:00
Richard Smith
4576a77b80 PR33222: Require the declared return type not the actual return type to
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
2018-09-10 06:35:32 +00:00
Richard Smith
4ced5d751b Part of PR33222: defer enforcing return type mismatch for dependent
friend function declarations of class templates.

llvm-svn: 341775
2018-09-10 05:32:13 +00:00
Akira Hatanaka
2ccb31977c [Sema] Check that the destructor for each element of class type is
accessible from the context where aggregate initialization occurs.

rdar://problem/38168772

Differential Revision: https://reviews.llvm.org/D45898

llvm-svn: 341629
2018-09-07 02:38:01 +00:00
Richard Smith
5159bbad8b PR38627: Fix handling of exception specification adjustment for
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
2018-09-05 22:30:37 +00:00
Richard Smith
59ef620059 Add test file missed from r341097.
llvm-svn: 341099
2018-08-30 19:17:11 +00:00
Richard Smith
218538ebe9 Add missing -Wc++11-compat / -Wc++14-compat warnings for:
* generic lambdas
 * return type deduction
 * class template argument deduction

llvm-svn: 341098
2018-08-30 19:16:35 +00:00
Aaron Ballman
57deab77de Thread safety analysis no longer hands when analyzing a self-referencing initializer.
This fixes PR38640.

llvm-svn: 340636
2018-08-24 18:48:35 +00:00
Aaron Puchert
c3e37b7538 Thread safety analysis: Allow relockable scopes
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
2018-08-22 22:14:53 +00:00
Erik Pilkington
63e7ab18e5 Address Aaron Ballman's post-commit review comments from r340306, NFC
llvm-svn: 340311
2018-08-21 17:50:10 +00:00
Erik Pilkington
5a559e64a9 Add a new flag and attributes to control static destructor registration
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
2018-08-21 17:24:06 +00:00
Richard Smith
e43e2b3667 Model type attributes as regular Attrs.
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
2018-08-20 21:47:29 +00:00
Nick Desaulniers
1aaf524ea1 [SEMA] add more -Wfloat-conversion to compound assigment analysis
Summary: Fixes Bug: https://bugs.llvm.org/show_bug.cgi?id=27061

Reviewers: aaron.ballman, acoomans

Reviewed By: aaron.ballman, acoomans

Subscribers: acoomans, cfe-commits, srhines, pirama

Differential Revision: https://reviews.llvm.org/D50467

llvm-svn: 339581
2018-08-13 16:38:07 +00:00
Martin Bohme
4e1293b5e1 Summary:Add clang::reinitializes attribute
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
2018-08-13 14:11:03 +00:00
Haojian Wu
74e0f40d98 Revert "Allow relockable scopes with thread safety attributes."
This reverts commit r339456.

The change introduces a new crash, see

class SCOPED_LOCKABLE FileLock {
 public:
  explicit FileLock()
      EXCLUSIVE_LOCK_FUNCTION(file_);
  ~FileLock() UNLOCK_FUNCTION(file_);
  void Lock() EXCLUSIVE_LOCK_FUNCTION(file_);
  Mutex file_;
};

void relockShared2() {
  FileLock file_lock;
  file_lock.Lock();
}

llvm-svn: 339558
2018-08-13 12:50:30 +00:00
Aaron Ballman
a97e4dc899 Allow relockable scopes with thread safety attributes.
Patch by Aaron Puchert

llvm-svn: 339456
2018-08-10 17:33:47 +00:00
Richard Smith
2e34bbd8e8 PR38286: Don't crash when attempting to define a constructor for an
incomplete class template.

llvm-svn: 339210
2018-08-08 00:42:42 +00:00
Richard Smith
06f71b5bd8 [constexpr] Support for constant evaluation of __builtin_memcpy and
__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
2018-08-04 00:57:17 +00:00
Aaron Ballman
eaa18e60eb Properly add shared locks to the initial list of locks being tracked, instead of assuming unlock functions always use exclusive locks.
Patch by Aaron Puchert.

llvm-svn: 338912
2018-08-03 19:37:45 +00:00
Michael Kruse
dc5ce72afa Append new attributes to the end of an AttributeList.
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
2018-08-03 01:21:16 +00:00
Hans Wennborg
6bd4f924e7 Revert r338455 "[constexpr] Support for constant evaluation of __builtin_memcpy and __builtin_memmove (in non-type-punning cases)."
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
2018-08-01 17:51:23 +00:00
Richard Smith
ad5bbcceb7 Avoid exposing name for range-based for '__range' variables in lifetime warnings.
llvm-svn: 338467
2018-08-01 01:03:33 +00:00
Richard Smith
f4e248c23e [P0936R0] add [[clang::lifetimebound]] attribute
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
2018-08-01 00:33:25 +00:00
Richard Smith
96beffba15 [constexpr] Support for constant evaluation of __builtin_memcpy and
__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
2018-07-31 23:35:09 +00:00
Richard Smith
5f2a349280 PR38355 Prevent infinite recursion when checking initializer lifetime if
an initializer is self-referential.

llvm-svn: 338230
2018-07-30 07:19:54 +00:00
Erik Pilkington
69770d3d7a [Sema] Use a TreeTransform to extract deduction guide parameter types
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
2018-07-27 21:23:48 +00:00
Erik Pilkington
dd0b344339 [Sema] Fix a crash by completing a type before using it
Only apply this exception on a type that we're able to check.

rdar://41903969

Differential revision: https://reviews.llvm.org/D49868

llvm-svn: 338089
2018-07-26 23:40:42 +00:00
Richard Smith
ef6c43dc0c Refactor checking of switch conditions and case values.
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
2018-07-26 18:41:30 +00:00
Aaron Ballman
1b58759d82 Allow thread safety annotation lock upgrading and downgrading.
Patch thanks to Aaron Puchert!

llvm-svn: 338024
2018-07-26 13:03:16 +00:00
Richard Smith
a3fd116219 Don't lifetime-extend or track lifetime problems through the LHS of '->*'.
Fixes a false-positive warning found by selfhost.

llvm-svn: 337857
2018-07-24 21:18:30 +00:00
Roman Lebedev
d55661db3c [Sema] Mark implicitly-inserted ICE's as being part of explicit cast (PR38166)
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
2018-07-24 08:16:50 +00:00
Richard Smith
3e6101b4b7 Add missing testcase update for r337790.
llvm-svn: 337792
2018-07-24 01:23:36 +00:00
Richard Smith
0e3102d1dc Warn if a local variable's initializer retains a pointer/reference to a
non-lifetime-extended temporary object.

llvm-svn: 337790
2018-07-24 00:55:08 +00:00
Richard Smith
f66e4f7dbd Support lifetime-extension of conditional temporaries.
llvm-svn: 337767
2018-07-23 22:56:45 +00:00
Erik Pilkington
a3a462e5ca [Sema] Fix crash on BlockExprs in a default member initializers
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
2018-07-23 22:47:37 +00:00
Richard Smith
6a32c0589c Do not try to perform lifetime-extension through conditional
expressions.

CodeGen can't cope with that yet. Instead, produce a "not supported"
warning for now and don't extend lifetime.

llvm-svn: 337744
2018-07-23 21:21:24 +00:00
Richard Smith
afe48f9d68 Fold -Wreturn-stack-address into general initialization lifetime
checking.

llvm-svn: 337743
2018-07-23 21:21:22 +00:00
Erich Keane
c764e9a87e Update to -r337585, allow scoped enum inits in -pedantic
llvm-svn: 337738
2018-07-23 21:08:13 +00:00
Richard Smith
ca975b2f58 Fold dangling-field warning into general initialization lifetime checks.
This reinstates r337627, reverted in r337671, with a fix to correctly
handle the lvalueness of array subscript expressions on pointers.

llvm-svn: 337726
2018-07-23 18:50:26 +00:00
Erich Keane
1ddd4bf87f Prevent Scoped Enums from being Integral constant expressions:
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
2018-07-20 17:42:09 +00:00
Erich Keane
3efe00206f Implement cpu_dispatch/cpu_specific Multiversioning
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
2018-07-20 14:13:28 +00:00
Erich Keane
a67eb91047 Enable C++2a Chrono Literals
C++2a via http://wg21.link/p0355 permits the library
literals of 'd' and 'y'. This patch enables them in the
Lexer so that they can be properly parsed.

Note that 'd' gets confused with the hex character, so
modifications to how octal, binary, and decimal numbers are
parsed were required. Since this is simply making previously
invalid code legal, this should be fine.

Hex still greedily parses the 'd' as a hexit, since it would
a: violate [lex.ext]p1
b: break existing code.

Differential Revision: https://reviews.llvm.org/D49504

llvm-svn: 337454
2018-07-19 13:36:57 +00:00
Erich Keane
7963e8bebb Add support for __declspec(code_seg("segname"))
This patch uses CodeSegAttr to represent __declspec(code_seg) rather than 
building on the existing support for #pragma code_seg.
The code_seg declspec is applied on functions and classes. This attribute 
enables the placement of code into separate named segments, including compiler-
generated codes and template instantiations.

For more information, please see the following:
https://msdn.microsoft.com/en-us/library/dn636922.aspx

This patch fixes the regression for the support for attribute ((section).
746b78de78

Patch by Soumi Manna (Manna)
Differential Revision: https://reviews.llvm.org/D48841

llvm-svn: 337420
2018-07-18 20:04:48 +00:00
Richard Smith
d87aab939a Restructure checking for, and warning on, lifetime extension.
This change implements C++ DR1696, which makes initialization of a
reference member of a class from a temporary object ill-formed. The
standard wording here is imprecise, but we interpret it as meaning that
any time a mem-initializer would result in lifetime extension, the
program is ill-formed.

This reinstates r337226, reverted in r337255, with a fix for the
InitializedEntity alignment problem that was breaking ARM buildbots.

llvm-svn: 337329
2018-07-17 22:24:09 +00:00
Benjamin Kramer
c41e096bda Revert "[Sema] Reword warning for constant captures that are not required"
This reverts commit r337152. This applies to non-constants too. The real
explanation is that the capture is not ODR-used, but putting that into
the warning message seems ... worse.

llvm-svn: 337278
2018-07-17 13:17:01 +00:00
Florian Hahn
0aa117dd2c Temporarily revert r337226 "Restructure checking for, and warning on, lifetime extension."
This change breaks on ARM because pointers to clang::InitializedEntity are only
4 byte aligned and do not have 3 bits to store values. A possible solution
would be to change the fields in clang::InitializedEntity to enforce a bigger
alignment requirement.

The error message is

llvm/include/llvm/ADT/PointerIntPair.h:132:3: error: static_assert failed "PointerIntPair with integer size too large for pointer"
  static_assert(IntBits <= PtrTraits::NumLowBitsAvailable,
include/llvm/ADT/PointerIntPair.h:73:13: note: in instantiation of template class 'llvm::PointerIntPairInfo<const clang::InitializedEntity *, 3, llvm::PointerLikeTypeTraits<const clang::InitializedEntity *> >' requested here
    Value = Info::updateInt(Info::updatePointer(0, PtrVal),
llvm/include/llvm/ADT/PointerIntPair.h:51:5: note: in instantiation of member function 'llvm::PointerIntPair<const clang::InitializedEntity *, 3, (anonymous namespace)::LifetimeKind, llvm::PointerLikeTypeTraits<const clang::InitializedEntity *>, llvm::PointerIntPairInfo<const clang::InitializedEntity *, 3, llvm::PointerLikeTypeTraits<const clang::InitializedEntity *> > >::setPointerAndInt' requested here
    setPointerAndInt(PtrVal, IntVal);
    ^
llvm/tools/clang/lib/Sema/SemaInit.cpp:6237:12: note: in instantiation of member function 'llvm::PointerIntPair<const clang::InitializedEntity *, 3, (anonymous namespace)::LifetimeKind, llvm::PointerLikeTypeTraits<const clang::InitializedEntity *>, llvm::PointerIntPairInfo<const clang::InitializedEntity *, 3, llvm::PointerLikeTypeTraits<const clang::InitializedEntity *> > >::PointerIntPair' requested here
    return {Entity, LK_Extended};

Full log here:
http://lab.llvm.org:8011/builders/clang-cmake-armv7-global-isel/builds/1330
http://lab.llvm.org:8011/builders/clang-cmake-armv7-full/builds/1394

llvm-svn: 337255
2018-07-17 09:23:31 +00:00
Richard Smith
0a9969b36b Restructure checking for, and warning on, lifetime extension.
This change implements C++ DR1696, which makes initialization of a
reference member of a class from a temporary object ill-formed. The
standard wording here is imprecise, but we interpret it as meaning that
any time a mem-initializer would result in lifetime extension, the
program is ill-formed.

llvm-svn: 337226
2018-07-17 00:11:41 +00:00
Benjamin Kramer
c8c90e5b40 [Sema] Reword warning for constant captures that are not required
This is one of the darker corners of C++, make it clear that this is
about constants and rephrase it a bit.

Before: lambda capture 'i' is not required to be captured for this use
After:  lambda capture of constant 'i' is not required for this use
llvm-svn: 337152
2018-07-16 09:52:02 +00:00