Commit Graph

4875 Commits

Author SHA1 Message Date
Nicolas Lesser f53d172710 Added a better diagnostic when using the delete operator with lambdas
Summary:
This adds a new error for missing parentheses around lambdas in delete operators.

```
int main() {
  delete []() { return new int(); }();
}
```

This will result in:

```
test.cpp:2:3: error: '[]' after delete interpreted as 'delete[]'
  delete []() { return new int(); }();
  ^~~~~~~~~
test.cpp:2:9: note: add parentheses around the lambda
  delete []() { return new int(); }();
        ^
        (                          )
```

Reviewers: rsmith

Reviewed By: rsmith

Subscribers: riccibruno, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D36357

llvm-svn: 361119
2019-05-19 15:07:58 +00:00
Richard Smith a933030f84 [c++20] P1327R1: Support for typeid applied to objects of polymorphic
class type in constant evaluation.

This reinstates r360977, reverted in r360987, now that its rerequisite
patch is reinstated and fixed.

llvm-svn: 361067
2019-05-17 19:19:28 +00:00
Nico Weber 762b3ef078 Attempt to fix test on Windows after r360998
llvm-svn: 361054
2019-05-17 17:33:54 +00:00
Richard Smith 51ce8444f0 Fix crash if, during evaluation of __builtin_object_size, we try to load
through an invalid base.

llvm-svn: 360998
2019-05-17 08:01:34 +00:00
Richard Smith ee0ce302c5 Refactor constant evaluation of typeid(T) to track a symbolic type_info
object rather than tracking the originating expression.

This is groundwork for supporting polymorphic typeid expressions. (Note
that this somewhat regresses our support for DR1968, but it turns out
that that never actually worked anyway, at least in non-trivial cases.)

This reinstates r360974, reverted in r360988, with a fix for a
static_assert failure on 32-bit builds: force Type base class to have
8-byte alignment like the rest of Clang's AST nodes.

llvm-svn: 360995
2019-05-17 07:06:46 +00:00
Chris Bieneman a971003e46 Revert Refactor constant evaluation of typeid(T) to track a symbolic type_info object rather than tracking the originating expression.
This reverts r360974 (git commit 7ee4307bd4)

llvm-svn: 360988
2019-05-17 05:46:03 +00:00
Chris Bieneman a5a4124c49 Revert [c++20] P1327R1: Support for typeid applied to objects of polymorphic class type in constant evaluation.
This reverts r360977 (git commit f51dc8d2f9)

llvm-svn: 360987
2019-05-17 05:45:57 +00:00
Richard Smith f51dc8d2f9 [c++20] P1327R1: Support for typeid applied to objects of polymorphic
class type in constant evaluation.

llvm-svn: 360977
2019-05-17 02:16:45 +00:00
Richard Smith 7ee4307bd4 Refactor constant evaluation of typeid(T) to track a symbolic type_info
object rather than tracking the originating expression.

This is groundwork for supporting polymorphic typeid expressions. (Note
that this somewhat regresses our support for DR1968, but it turns out
that that never actually worked anyway, at least in non-trivial cases.)

llvm-svn: 360974
2019-05-17 01:46:05 +00:00
Eric Fiselier 708afb56c1 Implement __builtin_LINE() et. al. to support source location capture.
Summary:
This patch implements the source location builtins `__builtin_LINE(), `__builtin_FUNCTION()`, `__builtin_FILE()` and `__builtin_COLUMN()`. These builtins are needed to implement [`std::experimental::source_location`](https://rawgit.com/cplusplus/fundamentals-ts/v2/main.html#reflection.src_loc.creation).

With the exception of `__builtin_COLUMN`, GCC also implements these builtins, and Clangs behavior is intended to match as closely as possible. 

Reviewers: rsmith, joerg, aaron.ballman, bogner, majnemer, shafik, martong

Reviewed By: rsmith

Subscribers: rnkovacs, loskutov, riccibruno, mgorny, kunitoki, alexr, majnemer, hfinkel, cfe-commits

Differential Revision: https://reviews.llvm.org/D37035

llvm-svn: 360937
2019-05-16 21:04:15 +00:00
Richard Smith 7bd54ab586 [c++20] For P1327R1: support dynamic_cast in constant expression
evaluation.

llvm-svn: 360806
2019-05-15 20:22:21 +00:00
Richard Smith 921f132a0f [c++20] P1064R0: Allow virtual function calls in constant expression
evaluation.

This reinstates r360559, reverted in r360580, with a fix to avoid
crashing if evaluation-for-overflow mode encounters a virtual call on an
object of a class with a virtual base class, and to generally not try to
resolve virtual function calls to objects whose (notional) vptrs are not
readable. (The standard rules are unclear here, but this seems like a
reasonable approach.)

llvm-svn: 360635
2019-05-13 23:35:21 +00:00
Marshall Clow ce78105558 Make more friendly with unions. Reviewed as https://reviews.llvm.org/D61858
llvm-svn: 360614
2019-05-13 19:29:23 +00:00
Hans Wennborg d5fb162563 Revert r360559 "[c++20] P1064R0: Allow virtual function calls in constant expression evaluation."
This caused Chromium builds to hit the new "can't handle virtual calls with
virtual bases" assert. Reduced repro coming up.

llvm-svn: 360580
2019-05-13 13:19:09 +00:00
Richard Smith dab287b550 PR41854: Don't assert when constant-evaluating a member function call on an invalid designator.
llvm-svn: 360560
2019-05-13 07:51:29 +00:00
Richard Smith 5c5be6b2f7 [c++20] P1064R0: Allow virtual function calls in constant expression
evaluation.

llvm-svn: 360559
2019-05-13 07:42:10 +00:00
Richard Smith debad6460b Reject attempts to call non-static member functions on objects outside
their lifetime in constant expressions.

This is undefined behavior per [class.cdtor]p2.

We continue to allow this for objects whose values are not visible
within the constant evaluation, because there's no way we can tell
whether the access is defined or not, existing code relies on the
ability to make such calls, and every other compiler allows such
calls.

This reinstates r360499, reverted in r360531.

llvm-svn: 360538
2019-05-12 09:39:08 +00:00
Richard Smith d3d6f4f65c Fix handling of objects under construction during constant expression
evaluation.

It's not enough to just track the LValueBase that we're evaluating, we
need to also track the path to the objects whose constructors are
running.

This reinstates r360464 (reverted in r360531) with a workaround for an
MSVC bug that previously caused the Windows bots to fail.

llvm-svn: 360537
2019-05-12 08:57:59 +00:00
Simon Pilgrim 73e8b67438 Revert rL360499 and rL360464 from cfe/trunk:
Reject attempts to call non-static member functions on objects outside
their lifetime in constant expressions.

This is undefined behavior per [class.cdtor]p2.

We continue to allow this for objects whose values are not visible
within the constant evaluation, because there's no way we can tell
whether the access is defined or not, existing code relies on the
ability to make such calls, and every other compiler allows such
calls.
........
Fix handling of objects under construction during constant expression
evaluation.

It's not enough to just track the LValueBase that we're evaluating, we
need to also track the path to the objects whose constructors are
running.
........
Fixes windows buildbots

llvm-svn: 360531
2019-05-11 20:21:59 +00:00
Richard Smith d05df0ef43 Reject attempts to call non-static member functions on objects outside
their lifetime in constant expressions.

This is undefined behavior per [class.cdtor]p2.

We continue to allow this for objects whose values are not visible
within the constant evaluation, because there's no way we can tell
whether the access is defined or not, existing code relies on the
ability to make such calls, and every other compiler allows such
calls.

llvm-svn: 360499
2019-05-11 02:00:06 +00:00
Richard Smith c0fe5eb39c Fix handling of objects under construction during constant expression
evaluation.

It's not enough to just track the LValueBase that we're evaluating, we
need to also track the path to the objects whose constructors are
running.

llvm-svn: 360464
2019-05-10 20:05:32 +00:00
Erik Pilkington f8ccf05293 [Sema] Mark array element destructors referenced during initialization
This fixes a crash where we would neglect to mark a destructor referenced for an
__attribute__((no_destory)) array. The destructor is needed though, since if an
exception is thrown we need to cleanup the elements.

rdar://48462498

Differential revision: https://reviews.llvm.org/D61165

llvm-svn: 360446
2019-05-10 17:52:26 +00:00
Akira Hatanaka c39a243da6 Assume `__cxa_allocate_exception` returns an under-aligned memory on
Darwin if the version of libc++abi isn't new enough to include the fix
in r319123

This patch resurrects r264998, which was committed to work around a bug
in libc++abi that was causing _cxa_allocate_exception to return a memory
that wasn't double-word aligned.

http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20160328/154332.html

In addition, this patch makes clang issue a warning if the type of the
thrown object requires an alignment that is larger than the minimum
guaranteed by the target C++ runtime.

rdar://problem/49864414

Differential Revision: https://reviews.llvm.org/D61667

llvm-svn: 360404
2019-05-10 02:16:37 +00:00
Richard Smith d9c6b039db DR1872: don't allow any calls to virtual functions in constant
evaluation.

Not even in cases where we would not actually perform virtual dispatch.

llvm-svn: 360370
2019-05-09 19:45:49 +00:00
Richard Smith 76b9027f35 [c++20] Add support for explicit(bool), as described in P0892R2.
Patch by Tyker!

Differential Revision: https://reviews.llvm.org/D60934

llvm-svn: 360311
2019-05-09 03:59:21 +00:00
Richard Smith b23c5e8c3d [c++20] Implement P0846R0: allow (ADL-only) calls to template-ids whose
template name is not visible to unqualified lookup.

In order to support this without a severe degradation in our ability to
diagnose typos in template names, this change significantly restructures
the way we handle template-id-shaped syntax for which lookup of the
template name finds nothing.

Instead of eagerly diagnosing an undeclared template name, we now form a
placeholder template-name representing a name that is known to not find
any templates. When the parser sees such a name, it attempts to
disambiguate whether we have a less-than comparison or a template-id.
Any diagnostics or typo-correction for the name are delayed until its
point of use.

The upshot should be a small improvement of our diagostic quality
overall: we now take more syntactic context into account when trying to
resolve an undeclared identifier on the left hand side of a '<'. In
fact, this works well enough that the backwards-compatible portion (for
an undeclared identifier rather than a lookup that finds functions but
no function templates) is enabled in all language modes.

llvm-svn: 360308
2019-05-09 03:31:27 +00:00
Richard Smith 2194fb6ed9 When typo-correcting a function name, consider correcting to a type name
for a function-style cast.

llvm-svn: 360302
2019-05-09 00:57:24 +00:00
Aaron Ballman 6de5576af7 Allow 'static' storage specifier on an out-of-line class member template declaration in MSVCCompat mode.
Patch by Soumi Manna.

llvm-svn: 360250
2019-05-08 13:24:36 +00:00
Sam McCall 835d67f6c7 [Sema] Correct typos in return statements so the return types of 'auto' functions are always deduced.
Summary:
e.g.
  auto foo() {
    return no_such_thing; // Return value is a TypoExpr
  }
  using T = decltype(foo()); // Uh-oh, undeduced auto.

Reviewers: rsmith

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D61649

llvm-svn: 360224
2019-05-08 05:49:42 +00:00
Hans Wennborg d2b9fc88c8 Revert r359949 "[clang] adding explicit(bool) from c++2a"
This caused Clang to start erroring on the following:

  struct S {
    template <typename = int> explicit S();
  };

  struct T : S {};

  struct U : T {
    U();
  };
  U::U() {}

  $ clang -c /tmp/x.cc
  /tmp/x.cc:10:4: error: call to implicitly-deleted default constructor of 'T'
  U::U() {}
     ^
  /tmp/x.cc:5:12: note: default constructor of 'T' is implicitly deleted
    because base class 'S' has no default constructor
  struct T : S {};
             ^
  1 error generated.

See discussion on the cfe-commits email thread.

This also reverts the follow-ups r359966 and r359968.

> this patch adds support for the explicit bool specifier.
>
> Changes:
> - The parsing for the explicit(bool) specifier was added in ParseDecl.cpp.
> - The storage of the explicit specifier was changed. the explicit specifier was stored as a boolean value in the FunctionDeclBitfields and in the DeclSpec class. now it is stored as a PointerIntPair<Expr*, 2> with a flag and a potential expression in CXXConstructorDecl, CXXDeductionGuideDecl, CXXConversionDecl and in the DeclSpec class.
> - Following the AST change, Serialization, ASTMatchers, ASTComparator and ASTPrinter were adapted.
> - Template instantiation was adapted to instantiate the potential expressions of the explicit(bool) specifier When instantiating their associated declaration.
> - The Add*Candidate functions were adapted, they now take a Boolean indicating if the context allowing explicit constructor or conversion function and this boolean is used to remove invalid overloads that required template instantiation to be detected.
> - Test for Semantic and Serialization were added.
>
> This patch is not yet complete. I still need to check that interaction with CTAD and deduction guides is correct. and add more tests for AST operations. But I wanted first feedback.
> Perhaps this patch should be spited in smaller patches, but making each patch testable as a standalone may be tricky.
>
> Patch by Tyker
>
> Differential Revision: https://reviews.llvm.org/D60934

llvm-svn: 360024
2019-05-06 09:51:10 +00:00
Richard Smith 2b45b267da P1286R2: Remove restriction that the exception specification of a
defaulted special member matches the implicit exception specification.

llvm-svn: 360011
2019-05-06 05:04:56 +00:00
Richard Smith 7d02ca4878 Use DiagRuntimeBehavior for -Wunsequenced to weed out false positives
where either the modification or the other access is unreachable.

This reverts r359984 (which reverted r359962). The bug in clang-tidy's
test suite exposed by the original commit was fixed in r360009.

llvm-svn: 360010
2019-05-06 04:14:01 +00:00
Richard Smith b9fb121a62 [c++20] Implement P1009R2: allow omitting the array bound in an array
new expression.

This was voted into C++20 as a defect report resolution, so we
retroactively apply it to all prior language modes (though it can never
actually be used before C++11 mode).

llvm-svn: 360006
2019-05-06 03:47:15 +00:00
Simon Pilgrim 4c3fbbf635 Revert rL359962 : Use DiagRuntimeBehavior for -Wunsequenced to weed out false positives
where either the modification or the other access is unreachable.
........
Try to fix buildbots

llvm-svn: 359984
2019-05-05 17:10:05 +00:00
Nicolas Lesser ee0571734f [C++] Interpret unknown identifier in parameter clause as unknown type
instead of as parameter name without a type.

llvm-svn: 359979
2019-05-05 12:15:17 +00:00
Hamza Sood 8205a814a6 [c++20] Implement P0428R2 - Familiar template syntax for generic lambdas
Differential Revision: https://reviews.llvm.org/D36527

llvm-svn: 359967
2019-05-04 10:49:46 +00:00
Richard Smith 5dbfa76334 Use DiagRuntimeBehavior for -Wunsequenced to weed out false positives
where either the modification or the other access is unreachable.

llvm-svn: 359962
2019-05-04 05:20:14 +00:00
Richard Smith 37be3363b5 Disallow the operand of __builtin_constant_p from modifying enclosing
state when it's encountered while evaluating a constexpr function.

We attempt to follow GCC trunk's behavior here, but it is somewhat
inscrutible, so our behavior is only approximately the same for now.
Specifically, we only permit modification of objects whose lifetime
began within the operand of the __builtin_constant_p. GCC appears to
have effectively the same restriction, but also some unknown restriction
based on where and how the local state of the constexpr function is
mentioned within the operand (see added testcases).

llvm-svn: 359958
2019-05-04 04:00:45 +00:00
Nicolas Lesser 5fe2ddbdf4 [clang] adding explicit(bool) from c++2a
this patch adds support for the explicit bool specifier.

Changes:
- The parsing for the explicit(bool) specifier was added in ParseDecl.cpp.
- The storage of the explicit specifier was changed. the explicit specifier was stored as a boolean value in the FunctionDeclBitfields and in the DeclSpec class. now it is stored as a PointerIntPair<Expr*, 2> with a flag and a potential expression in CXXConstructorDecl, CXXDeductionGuideDecl, CXXConversionDecl and in the DeclSpec class.
- Following the AST change, Serialization, ASTMatchers, ASTComparator and ASTPrinter were adapted.
- Template instantiation was adapted to instantiate the potential expressions of the explicit(bool) specifier When instantiating their associated declaration.
- The Add*Candidate functions were adapted, they now take a Boolean indicating if the context allowing explicit constructor or conversion function and this boolean is used to remove invalid overloads that required template instantiation to be detected.
- Test for Semantic and Serialization were added.

This patch is not yet complete. I still need to check that interaction with CTAD and deduction guides is correct. and add more tests for AST operations. But I wanted first feedback.
Perhaps this patch should be spited in smaller patches, but making each patch testable as a standalone may be tricky.

Patch by Tyker

Differential Revision: https://reviews.llvm.org/D60934

llvm-svn: 359949
2019-05-04 00:09:00 +00:00
Nico Weber ecc969caf9 Revert r359814 "[Sema] Emit warning for visibility attribute on internal-linkage declaration"
See cfe-commits thread for r359814.

llvm-svn: 359858
2019-05-03 03:16:07 +00:00
David Blaikie 5e32805050 SemaOverload: Complete candidates before emitting the error, to ensure diagnostics emitted (or suppressed) during completion don't interfere with the overload notes
Because diagnostics and their notes are not connected at the API level,
if the error message for an overload is emitted, then the overload
candidates are completed - if a diagnostic is emitted during that work,
the notes related to overload candidates would be attached to the latter
diagnostic, not the original error. Sort of worse, if the latter
diagnostic was disabled, the notes are disabled.

Reviewers: rsmith

Differential Revision: https://reviews.llvm.org/D61357

llvm-svn: 359854
2019-05-03 00:44:50 +00:00
Scott Linder daa3c5b132 [Sema] Emit warning for visibility attribute on internal-linkage declaration
GCC warns on these cases, but we currently just silently ignore the attribute.

Differential Revision: https://reviews.llvm.org/D61097

llvm-svn: 359814
2019-05-02 19:03:57 +00:00
Richard Smith bac77806c5 Diagnose non-dependent qualified friend function template declarations
that don't match any existing declaration. Don't get confused and treat
such declarations as template *specializations*.

llvm-svn: 359746
2019-05-02 00:49:05 +00:00
Volodymyr Sapsai 31f7c4aa77 [Parser] Avoid correcting delayed typos in array subscript multiple times.
We correct some typos in `ActOnArraySubscriptExpr` and
`ActOnOMPArraySectionExpr`, so when their result is `ExprError`, we can
end up correcting delayed typos in the same expressions again. In
general it is OK but when `NumTypos` is incorrect, we can hit the
assertion

> Assertion failed: (Entry != DelayedTypos.end() && "Failed to get the state for a TypoExpr!"), function getTypoExprState, file clang/lib/Sema/SemaLookup.cpp, line 5219.

Fix by replacing some subscript `ExprResult` with typo-corrected expressions
instead of keeping the original expressions. Thus if original expressions
contained `TypoExpr`, we'll use corrected expressions instead of trying to
correct them again.

rdar://problem/47403222

Reviewers: rsmith, erik.pilkington, majnemer

Reviewed By: erik.pilkington

Subscribers: jkorous, dexonsmith, cfe-commits

Differential Revision: https://reviews.llvm.org/D60848

llvm-svn: 359713
2019-05-01 19:24:50 +00:00
David Bolvansky efba22cb6c [Diagnostics] Support -Wtype-limits for GCC compatibility
Summary:
GCC's  -Wtype-limits (part of -Wextra):
Warn if a comparison is always true or always false due to the limited range of the data type

Reviewers: rsmith, aaron.ballman, lebedev.ri, thakis

Reviewed By: rsmith

Subscribers: lebedev.ri, jdoerfert, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D58841

llvm-svn: 359516
2019-04-29 23:24:00 +00:00
Richard Smith 31cfb311c5 Reinstate r359059, reverted in r359361, with a fix to properly prevent
us emitting the operand of __builtin_constant_p if it has side-effects.

Original commit message:

Fix interactions between __builtin_constant_p and constexpr to match
current trunk GCC.

GCC permits information from outside the operand of
__builtin_constant_p (but in the same constant evaluation context) to be
used within that operand; clang now does so too. A few other minor
deviations from GCC's behavior showed up in my testing and are also
fixed (matching GCC):
  * Clang now supports nullptr_t as the argument type for
    __builtin_constant_p
    * Clang now returns true from __builtin_constant_p if called with a
    null pointer
    * Clang now returns true from __builtin_constant_p if called with an
    integer cast to pointer type

llvm-svn: 359367
2019-04-27 02:58:17 +00:00
Jorge Gorbe Moya 1dbd42ab5b Revert Fix interactions between __builtin_constant_p and constexpr to match current trunk GCC.
This reverts r359059 (git commit 0b098754b7)

llvm-svn: 359361
2019-04-27 00:32:04 +00:00
Martin Storsjo 5be69bc68a [MinGW] Fix dllexport of explicit template instantiation
Contrary to MSVC, GCC/MinGW needs to have the dllexport attribute
on the template instantiation declaration, not on the definition.

Previously clang never marked explicit template instantiations as
dllexport in MinGW mode, if the instantiation had a previous
declaration, regardless of where the attribute was placed. This
makes Clang behave like GCC in this regard, and allows using the
same attribute form for both MinGW compilers.

This fixes PR40256.

Differential Revision: https://reviews.llvm.org/D61118

llvm-svn: 359285
2019-04-26 08:09:51 +00:00
Richard Smith bb750689d5 C++ DR2387: a variable template declared wtih (or instantiated with) a
const-qualified type is not implicitly given internal linkage. But a
variable template declared 'static' is.

This reinstates part of r359048, reverted in r359076.

llvm-svn: 359260
2019-04-26 01:51:08 +00:00
Richard Smith 0d923af492 Add missing diagnostic for explicit instantiation declarations naming
internal linkage entities.

Such constructs are ill-formed by [temp.explicit]p13. We make a special
exception to permit an invalid construct used by libc++ in some build
modes: its <valarray> header declares some functions with the
internal_linkage attribute and then (meaninglessly) provides explicit
instantiation declarations for them. Luckily, Clang happens to
effectively ignore the explicit instantiation declaration when
generating code in this case, and this change codifies that behavior.

This reinstates part of r359048, reverted in r359076. (The libc++ issue
triggering the rollback has been addressed.)

llvm-svn: 359259
2019-04-26 01:51:07 +00:00