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510 Commits

Author SHA1 Message Date
Matheus Izvekov 15f3cd6bfc
[clang] Implement ElaboratedType sugaring for types written bare
Without this patch, clang will not wrap in an ElaboratedType node types written
without a keyword and nested name qualifier, which goes against the intent that
we should produce an AST which retains enough details to recover how things are
written.

The lack of this sugar is incompatible with the intent of the type printer
default policy, which is to print types as written, but to fall back and print
them fully qualified when they are desugared.

An ElaboratedTypeLoc without keyword / NNS uses no storage by itself, but still
requires pointer alignment due to pre-existing bug in the TypeLoc buffer
handling.

---

Troubleshooting list to deal with any breakage seen with this patch:

1) The most likely effect one would see by this patch is a change in how
   a type is printed. The type printer will, by design and default,
   print types as written. There are customization options there, but
   not that many, and they mainly apply to how to print a type that we
   somehow failed to track how it was written. This patch fixes a
   problem where we failed to distinguish between a type
   that was written without any elaborated-type qualifiers,
   such as a 'struct'/'class' tags and name spacifiers such as 'std::',
   and one that has been stripped of any 'metadata' that identifies such,
   the so called canonical types.
   Example:
   ```
   namespace foo {
     struct A {};
     A a;
   };
   ```
   If one were to print the type of `foo::a`, prior to this patch, this
   would result in `foo::A`. This is how the type printer would have,
   by default, printed the canonical type of A as well.
   As soon as you add any name qualifiers to A, the type printer would
   suddenly start accurately printing the type as written. This patch
   will make it print it accurately even when written without
   qualifiers, so we will just print `A` for the initial example, as
   the user did not really write that `foo::` namespace qualifier.

2) This patch could expose a bug in some AST matcher. Matching types
   is harder to get right when there is sugar involved. For example,
   if you want to match a type against being a pointer to some type A,
   then you have to account for getting a type that is sugar for a
   pointer to A, or being a pointer to sugar to A, or both! Usually
   you would get the second part wrong, and this would work for a
   very simple test where you don't use any name qualifiers, but
   you would discover is broken when you do. The usual fix is to
   either use the matcher which strips sugar, which is annoying
   to use as for example if you match an N level pointer, you have
   to put N+1 such matchers in there, beginning to end and between
   all those levels. But in a lot of cases, if the property you want
   to match is present in the canonical type, it's easier and faster
   to just match on that... This goes with what is said in 1), if
   you want to match against the name of a type, and you want
   the name string to be something stable, perhaps matching on
   the name of the canonical type is the better choice.

3) This patch could expose a bug in how you get the source range of some
   TypeLoc. For some reason, a lot of code is using getLocalSourceRange(),
   which only looks at the given TypeLoc node. This patch introduces a new,
   and more common TypeLoc node which contains no source locations on itself.
   This is not an inovation here, and some other, more rare TypeLoc nodes could
   also have this property, but if you use getLocalSourceRange on them, it's not
   going to return any valid locations, because it doesn't have any. The right fix
   here is to always use getSourceRange() or getBeginLoc/getEndLoc which will dive
   into the inner TypeLoc to get the source range if it doesn't find it on the
   top level one. You can use getLocalSourceRange if you are really into
   micro-optimizations and you have some outside knowledge that the TypeLocs you are
   dealing with will always include some source location.

4) Exposed a bug somewhere in the use of the normal clang type class API, where you
   have some type, you want to see if that type is some particular kind, you try a
   `dyn_cast` such as `dyn_cast<TypedefType>` and that fails because now you have an
   ElaboratedType which has a TypeDefType inside of it, which is what you wanted to match.
   Again, like 2), this would usually have been tested poorly with some simple tests with
   no qualifications, and would have been broken had there been any other kind of type sugar,
   be it an ElaboratedType or a TemplateSpecializationType or a SubstTemplateParmType.
   The usual fix here is to use `getAs` instead of `dyn_cast`, which will look deeper
   into the type. Or use `getAsAdjusted` when dealing with TypeLocs.
   For some reason the API is inconsistent there and on TypeLocs getAs behaves like a dyn_cast.

5) It could be a bug in this patch perhaps.

Let me know if you need any help!

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Differential Revision: https://reviews.llvm.org/D112374
2022-07-27 11:10:54 +02:00
Jonas Devlieghere 888673b6e3
Revert "[clang] Implement ElaboratedType sugaring for types written bare"
This reverts commit 7c51f02eff because it
stills breaks the LLDB tests. This was  re-landed without addressing the
issue or even agreement on how to address the issue. More details and
discussion in https://reviews.llvm.org/D112374.
2022-07-14 21:17:48 -07:00
Matheus Izvekov 7c51f02eff
[clang] Implement ElaboratedType sugaring for types written bare
Without this patch, clang will not wrap in an ElaboratedType node types written
without a keyword and nested name qualifier, which goes against the intent that
we should produce an AST which retains enough details to recover how things are
written.

The lack of this sugar is incompatible with the intent of the type printer
default policy, which is to print types as written, but to fall back and print
them fully qualified when they are desugared.

An ElaboratedTypeLoc without keyword / NNS uses no storage by itself, but still
requires pointer alignment due to pre-existing bug in the TypeLoc buffer
handling.

---

Troubleshooting list to deal with any breakage seen with this patch:

1) The most likely effect one would see by this patch is a change in how
   a type is printed. The type printer will, by design and default,
   print types as written. There are customization options there, but
   not that many, and they mainly apply to how to print a type that we
   somehow failed to track how it was written. This patch fixes a
   problem where we failed to distinguish between a type
   that was written without any elaborated-type qualifiers,
   such as a 'struct'/'class' tags and name spacifiers such as 'std::',
   and one that has been stripped of any 'metadata' that identifies such,
   the so called canonical types.
   Example:
   ```
   namespace foo {
     struct A {};
     A a;
   };
   ```
   If one were to print the type of `foo::a`, prior to this patch, this
   would result in `foo::A`. This is how the type printer would have,
   by default, printed the canonical type of A as well.
   As soon as you add any name qualifiers to A, the type printer would
   suddenly start accurately printing the type as written. This patch
   will make it print it accurately even when written without
   qualifiers, so we will just print `A` for the initial example, as
   the user did not really write that `foo::` namespace qualifier.

2) This patch could expose a bug in some AST matcher. Matching types
   is harder to get right when there is sugar involved. For example,
   if you want to match a type against being a pointer to some type A,
   then you have to account for getting a type that is sugar for a
   pointer to A, or being a pointer to sugar to A, or both! Usually
   you would get the second part wrong, and this would work for a
   very simple test where you don't use any name qualifiers, but
   you would discover is broken when you do. The usual fix is to
   either use the matcher which strips sugar, which is annoying
   to use as for example if you match an N level pointer, you have
   to put N+1 such matchers in there, beginning to end and between
   all those levels. But in a lot of cases, if the property you want
   to match is present in the canonical type, it's easier and faster
   to just match on that... This goes with what is said in 1), if
   you want to match against the name of a type, and you want
   the name string to be something stable, perhaps matching on
   the name of the canonical type is the better choice.

3) This patch could exposed a bug in how you get the source range of some
   TypeLoc. For some reason, a lot of code is using getLocalSourceRange(),
   which only looks at the given TypeLoc node. This patch introduces a new,
   and more common TypeLoc node which contains no source locations on itself.
   This is not an inovation here, and some other, more rare TypeLoc nodes could
   also have this property, but if you use getLocalSourceRange on them, it's not
   going to return any valid locations, because it doesn't have any. The right fix
   here is to always use getSourceRange() or getBeginLoc/getEndLoc which will dive
   into the inner TypeLoc to get the source range if it doesn't find it on the
   top level one. You can use getLocalSourceRange if you are really into
   micro-optimizations and you have some outside knowledge that the TypeLocs you are
   dealing with will always include some source location.

4) Exposed a bug somewhere in the use of the normal clang type class API, where you
   have some type, you want to see if that type is some particular kind, you try a
   `dyn_cast` such as `dyn_cast<TypedefType>` and that fails because now you have an
   ElaboratedType which has a TypeDefType inside of it, which is what you wanted to match.
   Again, like 2), this would usually have been tested poorly with some simple tests with
   no qualifications, and would have been broken had there been any other kind of type sugar,
   be it an ElaboratedType or a TemplateSpecializationType or a SubstTemplateParmType.
   The usual fix here is to use `getAs` instead of `dyn_cast`, which will look deeper
   into the type. Or use `getAsAdjusted` when dealing with TypeLocs.
   For some reason the API is inconsistent there and on TypeLocs getAs behaves like a dyn_cast.

5) It could be a bug in this patch perhaps.

Let me know if you need any help!

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Differential Revision: https://reviews.llvm.org/D112374
2022-07-15 04:16:55 +02:00
Jonas Devlieghere 3968936b92
Revert "[clang] Implement ElaboratedType sugaring for types written bare"
This reverts commit bdc6974f92 because it
breaks all the LLDB tests that import the std module.

  import-std-module/array.TestArrayFromStdModule.py
  import-std-module/deque-basic.TestDequeFromStdModule.py
  import-std-module/deque-dbg-info-content.TestDbgInfoContentDequeFromStdModule.py
  import-std-module/forward_list.TestForwardListFromStdModule.py
  import-std-module/forward_list-dbg-info-content.TestDbgInfoContentForwardListFromStdModule.py
  import-std-module/list.TestListFromStdModule.py
  import-std-module/list-dbg-info-content.TestDbgInfoContentListFromStdModule.py
  import-std-module/queue.TestQueueFromStdModule.py
  import-std-module/stack.TestStackFromStdModule.py
  import-std-module/vector.TestVectorFromStdModule.py
  import-std-module/vector-bool.TestVectorBoolFromStdModule.py
  import-std-module/vector-dbg-info-content.TestDbgInfoContentVectorFromStdModule.py
  import-std-module/vector-of-vectors.TestVectorOfVectorsFromStdModule.py

https://green.lab.llvm.org/green/view/LLDB/job/lldb-cmake/45301/
2022-07-13 09:20:30 -07:00
Matheus Izvekov bdc6974f92
[clang] Implement ElaboratedType sugaring for types written bare
Without this patch, clang will not wrap in an ElaboratedType node types written
without a keyword and nested name qualifier, which goes against the intent that
we should produce an AST which retains enough details to recover how things are
written.

The lack of this sugar is incompatible with the intent of the type printer
default policy, which is to print types as written, but to fall back and print
them fully qualified when they are desugared.

An ElaboratedTypeLoc without keyword / NNS uses no storage by itself, but still
requires pointer alignment due to pre-existing bug in the TypeLoc buffer
handling.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Differential Revision: https://reviews.llvm.org/D112374
2022-07-13 02:10:09 +02:00
Roy Jacobson 0b89d1d59f [Sema] Add deprecation warnings for some compiler provided __has_* type traits
Some compiler provided type traits like __has_trivial_constructor have been documented
as deprecated for quite some time.
Still, some people apparently still use them, even though mixing them with concepts
and with deleted functions leads to weird results. There's also disagreement about some
edge cases between GCC (which Clang claims to follow) and MSVC.

This patch adds deprecation warnings for the usage of those builtins, except for __has_trivial_destructor
which doesn't have a GCC alternative.

I made the warning on by default, so I had to silence it for some tests but it's not too many.

Some (decade old) history of issues with those builtins:
https://github.com/llvm/llvm-project/issues/18187
https://github.com/llvm/llvm-project/issues/18559
https://github.com/llvm/llvm-project/issues/22161
https://github.com/llvm/llvm-project/issues/33063

The abseil usage of them that triggered me to add this warning:
https://github.com/abseil/abseil-cpp/issues/1201

Weird interaction of those builtins with C++20's conditionally trivial special member functions:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106085

Reviewed By: #clang-language-wg, aaron.ballman

Differential Revision: https://reviews.llvm.org/D129170
2022-07-12 19:24:17 +03:00
zoecarver 22c7a6dddd [objcxx] Fix `std::addressof` for `id`.
Differential Revision: https://reviews.llvm.org/D129384
2022-07-08 11:29:30 -07:00
Aaron Ballman 2cb2cd242c Change the behavior of implicit int diagnostics
C89 allowed a type specifier to be elided with the resulting type being
int, aka implicit int behavior. This feature was subsequently removed
in C99 without a deprecation period, so implementations continued to
support the feature. Now, as with implicit function declarations, is a
good time to reevaluate the need for this support.

This patch allows -Wimplicit-int to issue warnings in C89 mode (off by
default), defaults the warning to an error in C99 through C17, and
disables support for the feature entirely in C2x. It also removes a
warning about missing declaration specifiers that really was just an
implicit int warning in disguise and other minor related cleanups.
2022-05-04 08:35:47 -04:00
Devin Jeanpierre f2b31f06b7 re-roll-forward "[clang] Mark `trivial_abi` types as "trivially relocatable"".""
This reverts commit b0bc93da92.

Changes: `s/_WIN32/_WIN64/g` in clang/test/SemaCXX/attr-trivial-abi.cpp.

The calling convention is specific to 64-bit windows. It's even in the name: `CCK_MicrosoftWin64`.

After this, the test passes with both `-triple i686-pc-win32` and `-triple x86_64-pc-win32`. Phew!

Reviewed By: gribozavr2

Differential Revision: https://reviews.llvm.org/D123059
2022-04-28 14:53:59 +02:00
Zahira Ammarguellat b0bc93da92 Revert "[clang] roll-forward "[clang] Mark `trivial_abi` types as "trivially relocatable""."
This reverts commit 56d46b36fc.

The LIT test SemaCXX/attr-trivial-abi.cpp is failing with 32bit build on
Windows. All the lines with the ifdef WIN32 are asserting but they are
not expected to. It looks like the LIT test was not tested on a	32bit
build of the compiler.
2022-03-23 04:54:00 -07:00
Devin Jeanpierre 56d46b36fc [clang] roll-forward "[clang] Mark `trivial_abi` types as "trivially relocatable"".
This reverts commit 852afed5e0.

Changes since D114732:

On PS4, we reverse the expectation that classes whose constructor is deleted are not trivially relocatable. Because, at the moment, only classes which are passed in registers are trivially relocatable, and PS4 allows passing in registers if the copy constructor is deleted, the original assertions were broken on PS4.

(This is kinda similar to DR1734.)

Reviewed By: gribozavr2

Differential Revision: https://reviews.llvm.org/D119017
2022-02-04 20:17:34 +01:00
Dmitri Gribenko 852afed5e0 Revert "[clang] Mark `trivial_abi` types as "trivially relocatable"."
This reverts commit 19aa2db023. It breaks
a PS4 buildbot.
2022-02-03 22:31:44 +01:00
Devin Jeanpierre 19aa2db023 [clang] Mark `trivial_abi` types as "trivially relocatable".
This change enables library code to skip paired move-construction and destruction for `trivial_abi` types, as if they were trivially-movable and trivially-destructible. This offers an extension to the performance fix offered by `trivial_abi`: rather than only offering trivial-type-like performance for pass-by-value, it also offers it for library code that moves values but not as arguments.

For example, if we use `memcpy` for trivially relocatable types inside of vector reallocation, and mark `unique_ptr` as `trivial_abi` (via `_LIBCPP_ABI_ENABLE_UNIQUE_PTR_TRIVIAL_ABI` / `_LIBCPP_ABI_UNSTABLE` / etc.), this would speed up `vector<unique_ptr>::push_back` by 40% on my benchmarks. (Though note that in this case, the compiler could have done this anyway, but happens not to due to the inlining horizon.)

If accepted, I intend to follow up with exactly such changes to library code, including and especially `std::vector`, making them use a trivial relocation operation on trivially relocatable types.

**D50119 and P1144:**

This change is very similar to D50119, which was rejected from Clang. (That change was an implementation of P1144, which is not yet part of the C++ standard.)

The intent of this change, rather than trying to pick a winning proposal for trivial relocation operations, is to extend the behavior of `trivial_abi` in a way that could be made compatible with any such proposal. If P1144 or any similar proposal were accepted, then `trivial_abi`, `__is_trivially_relocatable`, and everything else in this change would be redefined in terms of that.

**Safety:**

It's worth pointing out, specifically, that `trivial_abi` already implies trivial relocatability in a narrow sense: a `trivial_abi` type, when passed by value, has its constructor run in one location, and its destructor run in another, after the type has been trivially relocated (through registers).

Trivial relocatability optimizations could change the number of paired constructor/destructor calls, but this seems unlikely to matter for `trivial_abi` types.

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D114732
2022-02-02 17:42:20 -08:00
Jeroen Dobbelaere a4fbae268f Revert "[Sema] check PseudoObject when rebuilding CXXOperatorCallExpr in template instantiation"
This reverts commit 0c047a8e13.

A number of buildbots started failing. Reverting for now.
2021-12-01 11:18:30 +01:00
Jeroen Dobbelaere 0c047a8e13 [Sema] check PseudoObject when rebuilding CXXOperatorCallExpr in template instantiation
The invocation of a unary or binary operator for type-dependent expressions is represented as a CXXOperatorCallExpr. Upon template instantiation, TreeTransform::RebuildCXXOperatorCallExpr checks for the case of an overloaded operator, but not for a (non-ObjC) PseudoObject, and will directly create a UnaryOperator or BinaryOperator.

Generalizing commit 0f99537eca from @akyrtzi to handle non-ObjC pseudo objects (and also handle the case of unary pseudo object inc/dec).

This fixes https://bugs.llvm.org/show_bug.cgi?id=51855

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D111639
2021-12-01 11:02:28 +01:00
Zarko Todorovski c79345fb7b [NFC][Clang][test] Inclusive language: Remove and rephrase uses of sanity test/check in clang/test
Part of work to use more inclusive terms in clang/llvm.
2021-11-24 14:03:49 -05:00
David Blaikie aee4925507 Recommit: Compress formatting of array type names (int [4] -> int[4])
Based on post-commit review discussion on
2bd8493847 with Richard Smith.

Other uses of forcing HasEmptyPlaceHolder to false seem OK to me -
they're all around pointer/reference types where the pointer/reference
token will appear at the rightmost side of the left side of the type
name, so they make nested types (eg: the "int" in "int *") behave as
though there is a non-empty placeholder (because the "*" is essentially
the placeholder as far as the "int" is concerned).

This was originally committed in 277623f4d5

Reverted in f9ad1d1c77 due to breakages
outside of clang - lldb seems to have some strange/strong dependence on
"char [N]" versus "char[N]" when printing strings (not due to that name
appearing in DWARF, but probably due to using clang to stringify type
names) that'll need to be addressed, plus a few other odds and ends in
other subprojects (clang-tools-extra, compiler-rt, etc).
2021-10-21 11:34:43 -07:00
David Blaikie f9ad1d1c77 Revert "Compress formatting of array type names (int [4] -> int[4])"
Looks like lldb has some issues with this - somehow it causes lldb to
treat a "char[N]" type as an array of chars (prints them out
individually) but a "char [N]" is printed as a string. (even though the
DWARF doesn't have this string in it - it's something to do with the
string lldb generates for itself using clang)

This reverts commit 277623f4d5.
2021-10-14 14:49:25 -07:00
David Blaikie 277623f4d5 Compress formatting of array type names (int [4] -> int[4])
Based on post-commit review discussion on
2bd8493847 with Richard Smith.

Other uses of forcing HasEmptyPlaceHolder to false seem OK to me -
they're all around pointer/reference types where the pointer/reference
token will appear at the rightmost side of the left side of the type
name, so they make nested types (eg: the "int" in "int *") behave as
though there is a non-empty placeholder (because the "*" is essentially
the placeholder as far as the "int" is concerned).
2021-10-14 14:23:32 -07:00
Matheus Izvekov 03282f2fe1 [clang] C++98 implicit moves are back with a vengeance
After taking C++98 implicit moves out in D104500,
we put it back in, but now in a new form which preserves
compatibility with pure C++98 programs, while at the same time
giving almost all the goodies from P1825.

* We use the exact same rules as C++20 with regards to which
  id-expressions are move eligible. The previous
  incarnation would only benefit from the proper subset which is
  copy ellidable. This means we can implicit move, in addition:
  * Parameters.
  * RValue references.
  * Exception variables.
  * Variables with higher-than-natural required alignment.
  * Objects with different type from the function return type.
* We preserve the two-overload resolution, with one small tweak to the
  first one: If we either pick a (possibly converting) constructor which
  does not take an rvalue reference, or a user conversion operator which
  is not ref-qualified, we abort into the second overload resolution.

This gives C++98 almost all the implicit move patterns which we had created test
cases for, while at the same time preserving the meaning of these
three patterns, which are found in pure C++98 programs:
* Classes with both const and non-const copy constructors, but no move
  constructors, continue to have their non-const copy constructor
  selected.
* We continue to reject as ambiguous the following pattern:
```
struct A { A(B &); };
struct B { operator A(); };
A foo(B x) { return x; }
```
* We continue to pick the copy constructor in the following pattern:
```
class AutoPtrRef { };
struct AutoPtr {
  AutoPtr(AutoPtr &);
  AutoPtr();

  AutoPtr(AutoPtrRef);
  operator AutoPtrRef();
};
AutoPtr test_auto_ptr() {
  AutoPtr p;
  return p;
}
```

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Reviewed By: Quuxplusone

Differential Revision: https://reviews.llvm.org/D105756
2021-07-13 19:16:49 +02:00
Matheus Izvekov 7d2d5a3a6d [clang] Apply P1825 as Defect Report from C++11 up to C++20.
This extends the effects of [[ http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1825r0.html | P1825 ]] to all C++ standards from C++11 up to C++20.

According to Motion 23 from Cologne 2019, P1825R0 was accepted as a Defect Report, so we retroactively apply this all the way back to C++11.

Note that we also remove implicit moves from C++98 as an extension
altogether, since the expanded first overload resolution from P1825
can cause some meaning changes in C++98.
For example it can change which copy constructor is picked when both const
and non-const ones are available.

This also rips out warn_return_std_move since there are no cases where it would be worthwhile to suggest it.

This also fixes a bug with bailing into the second overload resolution
when encountering a non-rvref qualified conversion operator.
This was unnoticed until now, so two new test cases cover these.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D104500
2021-07-01 12:10:06 +02:00
Matheus Izvekov ced6b204d1 [clang] Implement P2266 Simpler implicit move
This Implements [[http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2021/p2266r1.html|P2266 Simpler implicit move]].

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Reviewed By: Quuxplusone

Differential Revision: https://reviews.llvm.org/D99005
2021-06-18 17:08:59 +02:00
Matheus Izvekov 12c90e2e25 [clang] NRVO: Improvements and handling of more cases.
This expands NRVO propagation for more cases:

Parse analysis improvement:
* Lambdas and Blocks with dependent return type can have their variables
  marked as NRVO Candidates.

Variable instantiation improvements:
* Fixes crash when instantiating NRVO variables in Blocks.
* Functions, Lambdas, and Blocks which have auto return type have their
  variables' NRVO status propagated. For Blocks with non-auto return type,
  as a limitation, this propagation does not consider the actual return
  type.

This also implements exclusion of VarDecls which are references to
dependent types.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Reviewed By: Quuxplusone

Differential Revision: https://reviews.llvm.org/D99696
2021-06-17 01:56:38 +02:00
Akira Hatanaka 809435e390 [Sema] Don't set BlockDecl's DoesNotEscape bit if the parameter type of
the function the block is passed to isn't a block pointer type

This patch fixes a bug where a block passed to a function taking a
parameter that doesn't have a block pointer type (e.g., id or reference
to a block pointer) was marked as noescape.

This partially fixes PR50043.

rdar://77030453

Differential Revision: https://reviews.llvm.org/D101097
2021-04-29 16:19:48 -07:00
Valeriy Savchenko 5780dbeee6 [-Wcalled-once] Do not run analysis on Obj-C++
Objective-C++ is not yet suppoerted.

rdar://76729552

Differential Revision: https://reviews.llvm.org/D100955
2021-04-22 15:20:52 +03:00
Erik Pilkington 803b79221e [SemaObjC] Fix a -Wbridge-cast false-positive
Clang used to emit a bad -Wbridge-cast diagnostic on the cast in the attached
test. This was because, after 09abecef7, struct __CFString was not added to
lookup, so the objc_bridge attribute wasn't getting duplicated onto the most
recent declaration, causing us to fail to find it in getObjCBridgeAttr. This
patch fixes this by instead walking through the redeclarations to find an
appropriate bridge attribute. rdar://72823399

Differential revision: https://reviews.llvm.org/D99661
2021-04-05 11:41:40 -04:00
Nathan James cb559c8d5e
[Sema] Add some basic lambda capture fix-its
Adds fix-its when users forget to explicitly capture variables or this in lambdas

Addresses https://github.com/clangd/clangd/issues/697

Reviewed By: kbobyrev

Differential Revision: https://reviews.llvm.org/D96975
2021-03-11 13:46:25 +00:00
Erik Pilkington c4355670b4 [Sema] Fix an assertion failure in -Wcompletion-handler
NamedDecl::getName() was being called on a constructor.
2021-01-25 13:02:02 -05:00
Alex Lorenz eddd1d192b [clang] add a `swift_async_name` attribute
The swift_async_name attribute provides a name for a function/method that can be used
to call the async overload of this method from Swift. This name specified in this attribute
assumes that the last parameter in the function/method its applied to is removed when
Swift invokes it, as the the Swift's await/async transformation implicitly constructs the callback.

Differential Revision: https://reviews.llvm.org/D92355
2020-12-04 15:55:29 -08:00
Alexey Bataev 07b568a9c8 [OPENMP]Fix PR47790: segfault in frontend while parsing Objective-C with OpenMP.
Need to check if the sema is actually finishing a function decl.

Differential Revision: https://reviews.llvm.org/D91376
2020-11-12 13:26:11 -08:00
Erik Pilkington 351317167e [SemaObjC] Fix composite pointer type calculation for `void*` and pointer to lifetime qualified ObjC pointer type
Fixes a regression introduced in 9a6f4d451c. rdar://70101809

Differential revision: https://reviews.llvm.org/D89475
2020-10-15 15:21:01 -04:00
Erik Pilkington 498c7fa48a [SemaObjC] Fix a crash on an invalid ternary with ARC pointers
FindCompositeObjCPointerType nulls out the subexpressions on error, so bail out
instead of trying to deref them.
2020-10-13 21:20:20 -04:00
Mark de Wever 0ce6d6b46e [Sema] List conversion validate character array.
The function `TryListConversion` didn't properly validate the following
part of the standard:

    Otherwise, if the parameter type is a character array [... ]
    and the initializer list has a single element that is an
    appropriately-typed string literal (8.5.2 [dcl.init.string]), the
    implicit conversion sequence is the identity conversion.

This caused the following call to `f()` to be ambiguous.
    void f(int(&&)[1]);
    void f(unsigned(&&)[1]);

    void g(unsigned i) {
      f({i});
    }

This issue only occurs when the initializer list had one element.

Differential Revision: https://reviews.llvm.org/D87561
2020-10-03 14:33:28 +02:00
Raul Tambre a1aa330b20 [Sema] Handle objc_super special lookup when checking builtin compatibility
objc_super is special and needs LookupPredefedObjCSuperType() called before performing builtin type comparisons.
This fixes an error when compiling macOS headers. A test is added.

Differential Revision: https://reviews.llvm.org/D87917
2020-09-18 20:51:55 +03:00
Vy Nguyen a707da4728 Clang crashed while checking for deletion of copy and move ctors
Crash:
       @     0x559d129463fc  clang::CXXRecordDecl::defaultedCopyConstructorIsDeleted()
        @     0x559d1288d3e5  clang::Sema::checkIllFormedTrivialABIStruct()::$_7::operator()()
        @     0x559d12884c34  clang::Sema::checkIllFormedTrivialABIStruct()
        @     0x559d1288412e  clang::Sema::CheckCompletedCXXClass()
        @     0x559d1288d843  clang::Sema::ActOnFinishCXXMemberSpecification()
        @     0x559d12020109  clang::Parser::ParseCXXMemberSpecification()
        @     0x559d1201e80c  clang::Parser::ParseClassSpecifier()
        @     0x559d1204e807  clang::Parser::ParseDeclarationSpecifiers()
        @     0x559d120e9aa9  clang::Parser::ParseSingleDeclarationAfterTemplate()
        @     0x559d120e8f21  clang::Parser::ParseTemplateDeclarationOrSpecialization()
        @     0x559d120e8886  clang::Parser::ParseDeclarationStartingWithTemplate()
        @     0x559d1204a1d4  clang::Parser::ParseDeclaration()
        @     0x559d12004b1d  clang::Parser::ParseExternalDeclaration()
        @     0x559d12017689  clang::Parser::ParseInnerNamespace()
        @     0x559d12017024  clang::Parser::ParseNamespace()
        @     0x559d1204a29b  clang::Parser::ParseDeclaration()
        @     0x559d12004c74  clang::Parser::ParseExternalDeclaration()

    Subscribers: cfe-commits

    Tags: #clang

    Differential Revision: https://reviews.llvm.org/D83263
2020-07-07 14:40:37 -04:00
Erik Pilkington 69d2fa9ed1 [SemaObjC] Fix a crash on invalid when 'auto' is used in a @property
rdar://48506879
2020-06-24 12:11:39 -04:00
Haojian Wu 58ea1059df [AST][RecoveryExpr] Build recovery expressions by default for C++.
Reland https://reviews.llvm.org/D76696
All known crashes have been fixed, another attemption.

We have rolled out this to all internal users for a while, didn't see
big issues, we consider it is stable enough.

Reviewed By: sammccall

Subscribers: rsmith, hubert.reinterpretcast, ebevhan, jkorous, arphaman, kadircet, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78350
2020-06-12 15:21:38 +02:00
Akira Hatanaka f466f0beda Disallow trivial_abi on a class if all copy and move constructors are
deleted

Instead of forcing the class to be passed in registers, which was what
r350920 did, issue a warning and inform the user that the attribute
cannot be used.

For more background, see this discussion:
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20190128/259907.html

This fixes PR39683.

rdar://problem/47308221

Differential Revision: https://reviews.llvm.org/D57626
2020-06-10 14:12:13 -07:00
Richard Smith 825e3bb580 PR46209: properly determine whether a copy assignment operator is
trivial.

We previously took a shortcut by assuming that if a subobject had a
trivial copy assignment operator (with a few side-conditions), we would
always invoke it, and could avoid going through overload resolution.
That turns out to not be correct in the presenve of ref-qualifiers (and
also won't be the case for copy-assignments with requires-clauses
either). Use the same logic for lazy declaration of copy-assignments
that we use for all other special member functions.

Previously committed as c57f8a3a20. This
now also includes an extension of LLDB's workaround for handling special
members without the help of Sema to cover copy assignments.
2020-06-05 16:05:32 -07:00
Jonas Devlieghere df53f09056 Revert "PR46209: properly determine whether a copy assignment operator is"
This reverts commit c57f8a3a20.
2020-06-04 23:45:36 -07:00
Richard Smith c57f8a3a20 PR46209: properly determine whether a copy assignment operator is
trivial.

We previously took a shortcut by assuming that if a subobject had a
trivial copy assignment operator (with a few side-conditions), we would
always invoke it, and could avoid going through overload resolution.
That turns out to not be correct in the presenve of ref-qualifiers (and
also won't be the case for copy-assignments with requires-clauses
either). Use the same logic for lazy declaration of copy-assignments
that we use for all other special member functions.
2020-06-04 19:19:01 -07:00
Haojian Wu 89d9912cbf [AST] dont invaliate VarDecl when the initializer contains errors.
Summary:
This patch contains 2 separate changes:
1) the initializer of a variable should play no part in decl "invalid" bit;
2) preserve the invalid initializer via recovery exprs;

With 1), we will regress the diagnostics (one big regression is that we loose
the "selected 'begin' function with iterator type" diagnostic in for-range stmt;
but with 2) together, we don't have regressions (the new diagnostics seems to be
improved).

Reviewers: sammccall

Reviewed By: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78116
2020-04-21 10:53:35 +02:00
Haojian Wu 9657385960 [AST] Dont invalide VarDecl even the default initializaiton is failed.
Summary:
This patch would cause clang emit more diagnostics, but it is much better than https://reviews.llvm.org/D76831

```cpp
struct A {
  A(int);
  ~A() = delete;
};
void k() {
  A a;
}

```

before the patch:

/tmp/t3.cpp:24:5: error: no matching constructor for initialization of 'A'
  A a;
    ^
/tmp/t3.cpp:20:3: note: candidate constructor not viable: requires 1 argument, but 0 were provided
  A(int);
  ^
/tmp/t3.cpp:19:8: note: candidate constructor (the implicit copy constructor) not viable: requires 1 argument, but 0 were provided
struct A {

After the patch:

/tmp/t3.cpp:24:5: error: no matching constructor for initialization of 'A'
  A a;
    ^
/tmp/t3.cpp:20:3: note: candidate constructor not viable: requires 1 argument, but 0 were provided
  A(int);
  ^
/tmp/t3.cpp:19:8: note: candidate constructor (the implicit copy constructor) not viable: requires 1 argument, but 0 were provided
struct A {
       ^
/tmp/t3.cpp:24:5: error: attempt to use a deleted function
  A a;
    ^
/tmp/t3.cpp:21:3: note: '~A' has been explicitly marked deleted here
  ~A() = delete;

Reviewers: sammccall

Reviewed By: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D77395
2020-04-14 12:58:48 +02:00
zoecarver b25ec45809 Fix __is_pointer builtin type trait to work with Objective-C pointer types.
Summary: 5ade17e broke __is_pointer for Objective-C pointer types. This patch fixes the builtin and re-applies the change to type_traits.

Tags: #clang, #libc

Differential Revision: https://reviews.llvm.org/D77519
2020-04-08 10:02:53 -07:00
Richard Smith 88c7ffaf94 Form invalid template-id annotations when parsing a construct that is
required to be a template-id but names an undeclared identifier.
2020-03-27 20:27:42 -07:00
Anastasia Stulova fa755d3e71 [Sema][C++] Propagate conversion kind to specialize the diagnostics
Compute and propagate conversion kind to diagnostics helper in C++
to provide more specific diagnostics about incorrect implicit
conversions in assignments, initializations, params, etc...

Duplicated some diagnostics as errors because C++ is more strict.

Tags: #clang

Differential Revision: https://reviews.llvm.org/D74116
2020-02-25 16:05:37 +00:00
Richard Smith 9a6f4d451c Clean up and slightly generalize implementation of composite pointer
type computation, in preparation for P0388R4, which adds another few
cases here.

We now properly handle forming multi-level composite pointer types
involving nested Objective-C pointer types (as is consistent with
including them as part of the notion of 'similar types' on which this
rule is based). We no longer lose non-CVR qualifiers on nested pointer
types.
2020-01-10 16:12:00 -08:00
Richard Smith fbf915f01d Add a FIXME and corresponding test coverage for some suspicious behavior
forming composite ObjC pointer types in comparisons.
2020-01-10 16:12:00 -08:00
Richard Smith f041e9ad70 CWG2352: Allow qualification conversions during reference binding.
The language wording change forgot to update overload resolution to rank
implicit conversion sequences based on qualification conversions in
reference bindings. The anticipated resolution for that oversight is
implemented here -- we order candidates based on qualification
conversion, not only on top-level cv-qualifiers, including ranking
reference bindings against non-reference bindings if they differ in
non-top-level qualification conversions.

For OpenCL/C++, this allows reference binding between pointers with
differing (nested) address spaces. This makes the behavior of reference
binding consistent with that of implicit pointer conversions, as is the
purpose of this change, but that pre-existing behavior for pointer
conversions is itself probably not correct. In any case, it's now
consistently the same behavior and implemented in only one place.

This reinstates commit de21704ba9,
reverted in commit d8018233d1, with
workarounds for some overload resolution ordering problems introduced by
CWG2352.
2020-01-09 18:24:06 -08:00
David Blaikie d8018233d1 Revert "CWG2352: Allow qualification conversions during reference binding."
This reverts commit de21704ba9.

Regressed/causes this to error due to ambiguity:

  void f(const int * const &);
  void f(int *);
  int main() {
    int * x;
    f(x);
  }

(in case it's important - the original case where this turned up was a
member function overload in a class template with, essentially:

  f(const T1&)
  f(T2*)

(where T1 == X const *, T2 == X))

It's not super clear to me if this ^ is expected behavior, in which case
I'm sorry about the revert & happy to look into ways to fix the original
code.
2019-12-27 12:27:20 -08:00