Commit Graph

9591 Commits

Author SHA1 Message Date
Kazu Hirata 6d9cd9199a Use llvm::all_of (NFC) 2022-08-14 16:25:36 -07:00
Nico Weber aacf1a9742 Revert "[clang] adds unary type transformations as compiler built-ins"
This reverts commit bc60cf2368.
Doesn't build on Windows and breaks gcc 9 build, see
https://reviews.llvm.org/D116203#3722094 and
https://reviews.llvm.org/D116203#3722128

Also revert two follow-ups. One fixed a warning added in
bc60cf2368, the other
makes use of the feature added in bc60cf2368
in libc++:

Revert "[libcxx][NFC] utilises compiler builtins for unary transform type-traits"
This reverts commit 06a1d917ef.

Revert "[Sema] Fix a warning"
This reverts commit c85abbe879.
2022-08-14 15:58:21 -04:00
Christopher Di Bella bc60cf2368 [clang] adds unary type transformations as compiler built-ins
Adds

* `__add_lvalue_reference`
* `__add_pointer`
* `__add_rvalue_reference`
* `__decay`
* `__make_signed`
* `__make_unsigned`
* `__remove_all_extents`
* `__remove_extent`
* `__remove_const`
* `__remove_volatile`
* `__remove_cv`
* `__remove_pointer`
* `__remove_reference`
* `__remove_cvref`

These are all compiler built-in equivalents of the unary type traits
found in [[meta.trans]][1]. The compiler already has all of the
information it needs to answer these transformations, so we can skip
needing to make partial specialisations in standard library
implementations (we already do this for a lot of the query traits). This
will hopefully improve compile times, as we won't need use as much
memory in such a base part of the standard library.

[1]: http://wg21.link/meta.trans

Co-authored-by: zoecarver

Reviewed By: aaron.ballman, rsmith

Differential Revision: https://reviews.llvm.org/D116203
2022-08-14 17:12:15 +00:00
Chuanqi Xu 0bc993edf4 [AST] [Modules] Introduce Decl::getNonTransparentDeclContext to handle exported friends
Closing https://github.com/llvm/llvm-project/issues/56826.

The root cause for pr56826 is: when we collect the template args for the
friend, we need to judge if the friend lives in file context. However,
if the friend lives in ExportDecl lexically, the judgement here is
invalid.

The solution is easy. We should judge the non transparent context and
the ExportDecl is transparent context. So the solution should be good.

A main concern may be the patch doesn't handle all the places of the
same defect. I think it might not be bad since the patch itself should
be innocent.

Reviewed By: erichkeane

Differential Revision: https://reviews.llvm.org/D131651
2022-08-12 11:50:35 +08:00
Ivan Murashko 557e32e002 [clang] SIGSEGV fix at clang::ASTContext::getRawCommentForDeclNoCacheImpl
The `File` might point to an invalid `FileID` when the AST is broken. That leads to clang/clangd crashes while processing comments. The relevant part of the crash is below
```
 #4 0x00007f1d7fbf95bc std::_Rb_tree<unsigned int, std::pair<unsigned int const, clang::RawComment*>, std::_Select1st<std::pair<unsigned int const, clang::RawComment*>>, std::less<unsigned int>, std::allocator<std::pair<unsigned int const
, clang::RawComment*>>>::_M_lower_bound(std::_Rb_tree_node<std::pair<unsigned int const, clang::RawComment*>> const*, std::_Rb_tree_node_base const*, unsigned int const&) const /usr/include/c++/8/bits/stl_tree.h:1911:2
 #5 0x00007f1d7fbf95bc std::_Rb_tree<unsigned int, std::pair<unsigned int const, clang::RawComment*>, std::_Select1st<std::pair<unsigned int const, clang::RawComment*>>, std::less<unsigned int>, std::allocator<std::pair<unsigned int const, clang::RawComment*>>>::lower_bound(unsigned int const&) const /usr/include/c++/8/bits/stl_tree.h:1214:56
 #6 0x00007f1d7fbf95bc std::map<unsigned int, clang::RawComment*, std::less<unsigned int>, std::allocator<std::pair<unsigned int const, clang::RawComment*>>>::lower_bound(unsigned int const&) const /usr/include/c++/8/bits/stl_map.h:1264:36
 #7 0x00007f1d7fbf95bc clang::ASTContext::getRawCommentForDeclNoCacheImpl(clang::Decl const*, clang::SourceLocation, std::map<unsigned int, clang::RawComment*, std::less<unsigned int>, std::allocator<std::pair<unsigned int const, clang::RawComment*>>> const&) const /home/ivanmurashko/local/llvm-project/clang/lib/AST/ASTContext.cpp:226:57
```

The corresponding LIT test that reproduces the crash was also added

Same issue is described at https://bugs.llvm.org/show_bug.cgi?id=49707

Reviewed By: gribozavr2

Differential Revision: https://reviews.llvm.org/D131675
2022-08-12 00:05:59 +01:00
Shafik Yaghmour 106774515b [Clang] Fix for Tighten restrictions on enum out of range diagnostic
Ok it looks like this is a bit more subtle, I broke the llvm-test-suite file
paq8p.cpp again. We need both conditions to be true Info.EvalMode ==
EvalInfo::EM_ConstantExpression && Info.InConstantContext. We need to be in a
context that requires a constant value but also in a constant expression context.

Differential Revision: https://reviews.llvm.org/D131704
2022-08-11 15:34:58 -07:00
Shafik Yaghmour 2608f553b8 [Clang] Tighten restrictions on enum out of range diagnostic
In D131528 using Info.EvalMode == EvalInfo::EM_ConstantExpression is not strict
enough to restrict the diagnostic to only constant expression contexts. It is
sometimes set in cases where we are still determining if we are in a constant
expression context.

Using InConstantContext will tighten the restriction.

Differential Revision: https://reviews.llvm.org/D131704
2022-08-11 13:44:26 -07:00
Shafik Yaghmour 4e458765aa [Clang] Restrict non fixed enum to a value outside the range of the enumeration values warning to context requiring a constant expression
In D131307 we allowed the diagnostic to be turned into a warning for a
transition period.

This had the side effect of triggering the warning in contexts not required to
be constant expression. This change will restrict the diagnostic to constant
expression contexts. This should reduce the fallout of this diagnostic.

Differential Revision: https://reviews.llvm.org/D131528
2022-08-10 11:12:01 -07:00
YingChi Long 55d3b79d15
[clang] add APValue type check in `TryPrintAsStringLiteral`
Fixes https://github.com/llvm/llvm-project/issues/57013

https://reviews.llvm.org/D115031 improved printing of non-type template
parameter args. But checking if the end of Inits is 0 without checking
if APValue is an integer, causes clang to segfault. This patch adds
the code to check the type. (May not be a proper bugfix.)

Reviewed By: aaron.ballman, lichray

Differential Revision: https://reviews.llvm.org/D131466
2022-08-10 08:42:59 +08:00
Matheus Izvekov 1d1a56929b
Clang: fix AST representation of expanded template arguments.
Extend clang's SubstTemplateTypeParm to represent the pack substitution index.

Fixes PR56099.

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

Differential Revision: https://reviews.llvm.org/D128113
2022-08-09 14:26:16 +02:00
Simon Pilgrim af0052ef74 Fix MSVC "not all control paths return a value" warning. NFC. 2022-08-09 09:55:57 +01:00
Balázs Kéri d4ff9eff76 [clang][ASTImporter] Improve import of functions with auto return type.
ASTImporter used to crash in some cases when a function is imported with
`auto` return type and the return type has references into the function.
The handling of such cases is improved and crash should not occur any more
but it is not fully verified, there are very many different types of
cases to care for.

Reviewed By: martong

Differential Revision: https://reviews.llvm.org/D130705
2022-08-09 09:20:06 +02:00
Fangrui Song 32197830ef [clang][clang-tools-extra] LLVM_NODISCARD => [[nodiscard]]. NFC 2022-08-09 07:11:18 +00:00
Shafik Yaghmour cc104113dd [Clang] Allow downgrading to a warning the diagnostic for setting a non fixed enum to a value outside the range of the enumeration values
In D130058 we diagnose the undefined behavior of setting the value outside the
range of the enumerations values for an enum without a fixed underlying type.

Based on feedback we will provide users to the ability to downgrade this
diagnostic to a waring to allow for a transition period. We expect to turn this
diagnostic to an error in the next release.

Differential Revision: https://reviews.llvm.org/D131307
2022-08-08 16:23:07 -07:00
Fangrui Song 3f18f7c007 [clang] LLVM_FALLTHROUGH => [[fallthrough]]. NFC
With C++17 there is no Clang pedantic warning or MSVC C5051.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D131346
2022-08-08 09:12:46 -07:00
Kazu Hirata 7542e72188 Use llvm::is_contained (NFC) 2022-08-07 00:16:17 -07:00
Timm Bäder d1942855c4 [clang] Consider array filler in MaybeElementDependentArrayfiller()
Any InitListExpr may have an array filler and since we may be evaluating
the array filler as well, we need to take into account that the array
filler expression might make the InitListExpr element dependent.

Fixes https://github.com/llvm/llvm-project/issues/56016

Differential Revision: https://reviews.llvm.org/D131155
2022-08-05 06:47:49 +02:00
Xiang Li 906e41f4e3 [HLSL] clang codeGen for HLSLShaderAttr.
Translate HLSLShaderAttr to IR level.
 1. Skip mangle for hlsl entry functions.
 2. Add function attribute for hlsl entry functions.

Reviewed By: Anastasia

Differential Revision: https://reviews.llvm.org/D124752
2022-08-04 21:23:57 -07:00
Fangrui Song 88501dc749 [Sema] -Wformat: support C23 format specifier %b %B
Close #56885: WG14 N2630 added %b to fprintf/fscanf and recommended %B for
fprintf. This patch teaches -Wformat %b for the printf/scanf family of functions
and %B for the printf family of functions.

glibc 2.35 and latest Android bionic added %b/%B printf support. From
https://www.openwall.com/lists/libc-coord/2022/07/ no scanf support is available
yet.

Like GCC, we don't test library support.

GCC 12 -Wformat -pedantic emits a warning:

> warning: ISO C17 does not support the ‘%b’ gnu_printf format [-Wformat=]

The behavior is not ported.

Note: `freebsd_kernel_printf` uses %b differently.

Reviewed By: aaron.ballman, dim, enh

Differential Revision: https://reviews.llvm.org/D131057
2022-08-04 10:26:31 -07:00
Corentin Jabot 127bf44385 [Clang][C++20] Support capturing structured bindings in lambdas
This completes the implementation of P1091R3 and P1381R1.

This patch allow the capture of structured bindings
both for C++20+ and C++17, with extension/compat warning.

In addition, capturing an anonymous union member,
a bitfield, or a structured binding thereof now has a
better diagnostic.

We only support structured bindings - as opposed to other kinds
of structured statements/blocks. We still emit an error for those.

In addition, support for structured bindings capture is entirely disabled in
OpenMP mode as this needs more investigation - a specific diagnostic indicate the feature is not yet supported there.

Note that the rest of P1091R3 (static/thread_local structured bindings) was already implemented.

at the request of @shafik, i can confirm the correct behavior of lldb wit this change.

Fixes https://github.com/llvm/llvm-project/issues/54300
Fixes https://github.com/llvm/llvm-project/issues/54300
Fixes https://github.com/llvm/llvm-project/issues/52720

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D122768
2022-08-04 10:12:53 +02:00
Corentin Jabot a274219600 Revert "[Clang][C++20] Support capturing structured bindings in lambdas"
This reverts commit 44f2baa380.

Breaks self builds and seems to have conformance issues.
2022-08-03 21:00:29 +02:00
Corentin Jabot 44f2baa380 [Clang][C++20] Support capturing structured bindings in lambdas
This completes the implementation of P1091R3 and P1381R1.

This patch allow the capture of structured bindings
both for C++20+ and C++17, with extension/compat warning.

In addition, capturing an anonymous union member,
a bitfield, or a structured binding thereof now has a
better diagnostic.

We only support structured bindings - as opposed to other kinds
of structured statements/blocks. We still emit an error for those.

In addition, support for structured bindings capture is entirely disabled in
OpenMP mode as this needs more investigation - a specific diagnostic indicate the feature is not yet supported there.

Note that the rest of P1091R3 (static/thread_local structured bindings) was already implemented.

at the request of @shafik, i can confirm the correct behavior of lldb wit this change.

Fixes https://github.com/llvm/llvm-project/issues/54300
Fixes https://github.com/llvm/llvm-project/issues/54300
Fixes https://github.com/llvm/llvm-project/issues/52720

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D122768
2022-08-03 20:00:01 +02:00
Jonas Paulsson 84831bdfed [SystemZ] Make 128 bit integers be aligned to 8 bytes.
The SystemZ ABI says that 128 bit integers should be aligned to only 8 bytes.

Reviewed By: Ulrich Weigand, Nikita Popov

Differential Revision: https://reviews.llvm.org/D130900
2022-08-03 15:39:54 +02:00
Timm Bäder 11e52ecf74 [clang] Short-circuit trivial constructors when evaluating arrays
VisitCXXConstructExpr() will later do something similar, but for large
arrays, we should try to do it once an not for every element.

Fixes #56774

Differential Revision: https://reviews.llvm.org/D130791
2022-08-03 10:38:15 +02:00
Gabriel Ravier 5674a3c880 Fixed a number of typos
I went over the output of the following mess of a command:

(ulimit -m 2000000; ulimit -v 2000000; git ls-files -z |
 parallel --xargs -0 cat | aspell list --mode=none --ignore-case |
 grep -E '^[A-Za-z][a-z]*$' | sort | uniq -c | sort -n |
 grep -vE '.{25}' | aspell pipe -W3 | grep : | cut -d' ' -f2 | less)

and proceeded to spend a few days looking at it to find probable typos
and fixed a few hundred of them in all of the llvm project (note, the
ones I found are not anywhere near all of them, but it seems like a
good start).

Differential Revision: https://reviews.llvm.org/D130827
2022-08-01 13:13:18 -04:00
Serge Pavlov 2bb7c54621 [Clang] Remove unused parameter. NFC
BinaryOperator::getFPFeatures get parameter, which is not used. Similar
methods of other AST nodes do not have any parameter.
2022-08-01 14:53:13 +07:00
Weverything fb7fa27f92 Preserve qualifiers when getting fully qualified type
15f3cd6bfc moved the handling of UsingType
to a later point in the function getFullyQualifiedType.  This moved it
after the removal of an ElaboratedType and its qualifiers.  However,
the qualifiers were not added back, causing the fully qualified type to
have a qualifier mismatch with the original type.  Make sure the
qualifers are added before continuing to fully qualify the type.
2022-07-29 19:42:54 -07:00
Shafik Yaghmour a0d6105162 [Clang] Fix handling of Max from getValueRange(...) in IntExprEvaluator::VisitCastExpr(...)
This is a follow-up to D130058 to fix how we handle the Max value we obtain from
getValueRange(...) in IntExprEvaluator::VisitCastExpr(...) which in the case of
an enum that contains an enumerator with the max integer value will overflow by
one.

The fix is to decrement the value of Max and use slt and ult for comparison Vs
sle and ule.`

Differential Revision: https://reviews.llvm.org/D130811
2022-07-29 19:17:42 -07:00
Shafik Yaghmour b364535304 [Clang] Diagnose ill-formed constant expression when setting a non fixed enum to a value outside the range of the enumeration values
DR2338 clarified that it was undefined behavior to set the value outside the
range of the enumerations values for an enum without a fixed underlying type.

We should diagnose this with a constant expression context.

Differential Revision: https://reviews.llvm.org/D130058
2022-07-28 15:27:50 -07:00
Chris Bieneman 6e56d0dbe3 Start support for HLSL `RWBuffer`
Most of the change here is fleshing out the HLSLExternalSemaSource with
builder implementations to build the builtin types. Eventually, I may
move some of this code into tablegen or a more managable declarative
file but I want to get the AST generation logic ready first.

This code adds two new types into the HLSL AST, `hlsl::Resource` and
`hlsl::RWBuffer`. The `Resource` type is just a wrapper around a handle
identifier, and is largely unused in source. It will morph a bit over
time as I work on getting the source compatability correct, but for now
it is a reasonable stand-in. The `RWBuffer` type is not ready for use.
I'm posting this change for review because it adds a lot of
infrastructure code and is testable.

There is one change to clang code outside the HLSL-specific logic here,
which addresses a behavior change introduced a long time ago in
967d438439. That change resulted in unintentionally breaking
situations where an incomplete template declaration was provided from
an AST source, and needed to be completed later by the external AST.
That situation doesn't happen in the normal AST importer flow, but can
happen when an AST source provides incomplete declarations of
templates. The solution is to annotate template specializations of
incomplete types with the HasExternalLexicalSource bit from the base
template.

Depends on D128012.

Differential Revision: https://reviews.llvm.org/D128569
2022-07-28 08:49:50 -05:00
Shafik Yaghmour 28cd7f86ed Revert "[Clang] Diagnose ill-formed constant expression when setting a non fixed enum to a value outside the range of the enumeration values"
This reverts commit a3710589f2.
2022-07-27 15:31:41 -07:00
Shafik Yaghmour a3710589f2 [Clang] Diagnose ill-formed constant expression when setting a non fixed enum to a value outside the range of the enumeration values
DR2338 clarified that it was undefined behavior to set the value outside the
range of the enumerations values for an enum without a fixed underlying type.

We should diagnose this with a constant expression context.

Differential Revision: https://reviews.llvm.org/D130058
2022-07-27 14:59:35 -07:00
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
Chuanqi Xu d35134485a [C++20] [Modules] Make the linkage consistent for class template and its
specialization

Previously in D120397, we've handled the linkage for function template
and its specialization. But we forgot to handle it for class templates
and their specialization. So we make it in the patch with the similar
approach.
2022-07-25 17:57:02 +08:00
Balázs Kéri acd80a29ae [clang][ASTImporter] Improved handling of functions with auto return type.
Avoid a crash if a function is imported that has auto return type that
references to a template with an expression-type of argument that
references into the function's body.
Fixes issue #56047

Reviewed By: martong

Differential Revision: https://reviews.llvm.org/D129640
2022-07-25 10:28:01 +02:00
Corentin Jabot c68baa73eb [clang] Fix incorrect constant folding of `if consteval`
Fixes https://github.com/llvm/llvm-project/issues/55638.

`if consteval` was evaluated incorrectly when in a
non-constant context that could be constant-folded.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D130437
2022-07-24 16:18:12 +02:00
Erich Keane 70c62f4cad [NFC] give getParentFunctionOrMethod a 'Lexical' parameter
Split up from the deferred concepts implementation, this function is
useful for determining the containing function of a different function.
However, in some cases it is valuable to instead get the lexical parent.
This adds a parameter to the existing function to allow a 'Lexical'
parameter to instead select the lexical parent.
2022-07-22 12:52:26 -07:00
Erich Keane 3ff86f9610 [NFC] Start saving InstantiatedFromDecl in non-template functions
In cases where a non-template function is defined inside a function
template, we don't have information about the original uninstantiated
version.  In the case of concepts instantiation, we will need the
ability to get back to the original template.  This patch splits a piece
of the deferred concepts instantaition patch off to accomplish the
storage of this, with minor runtime overhead, and zero additional
storage.
2022-07-22 12:37:14 -07:00
Iain Sandoe 97af17c5ca re-land [C++20][Modules] Update handling of implicit inlines [P1779R3]
re-land fixes an unwanted interaction with module-map modules, seen in
Greendragon testing.

This provides updates to
[class.mfct]:
Pre C++20 [class.mfct]p2:
  A member function may be defined (8.4) in its class definition, in
  which case it is an inline member function (7.1.2)
Post C++20 [class.mfct]p1:
  If a member function is attached to the global module and is defined
  in its class definition, it is inline.

and
[class.friend]:
Pre-C++20 [class.friend]p5
  A function can be defined in a friend declaration of a
  class . . . . Such a function is implicitly inline.
Post C++20 [class.friend]p7
  Such a function is implicitly an inline function if it is attached
  to the global module.

We add the output of implicit-inline to the TextNodeDumper, and amend
a couple of existing tests to account for this, plus add tests for the
cases covered above.

Differential Revision: https://reviews.llvm.org/D129045
2022-07-21 09:17:01 +01:00
serge-sans-paille f764dc99b3 [clang] Introduce -fstrict-flex-arrays=<n> for stricter handling of flexible arrays
Some code [0] consider that trailing arrays are flexible, whatever their size.
Support for these legacy code has been introduced in
f8f6324983 but it prevents evaluation of
__builtin_object_size and __builtin_dynamic_object_size in some legit cases.

Introduce -fstrict-flex-arrays=<n> to have stricter conformance when it is
desirable.

n = 0: current behavior, any trailing array member is a flexible array. The default.
n = 1: any trailing array member of undefined, 0 or 1 size is a flexible array member
n = 2: any trailing array member of undefined or 0 size is a flexible array member

This takes into account two specificities of clang: array bounds as macro id
disqualify FAM, as well as non standard layout.

Similar patch for gcc discuss here: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836

[0] https://docs.freebsd.org/en/books/developers-handbook/sockets/#sockets-essential-functions
2022-07-18 12:45:52 +02:00
Haojian Wu 5775c5d05c Remove an unsued-variable warning, NFC. 2022-07-15 14:40:52 +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
Shafik Yaghmour 80dec2ecff [Clang] Modify CXXMethodDecl::isMoveAssignmentOperator() to look through type sugar
AcceptedPublic

Currently CXXMethodDecl::isMoveAssignmentOperator() does not look though type
sugar and so if the parameter is a type alias it will not be able to detect
that the method is a move assignment operator. This PR fixes that and adds a set
of tests that covers that we correctly detect special member functions when
defaulting or deleting them.

This fixes: https://github.com/llvm/llvm-project/issues/56456

Differential Revision: https://reviews.llvm.org/D129591
2022-07-14 16:09:52 -07:00
Kazu Hirata cb2c8f694d [clang] Use value instead of getValue (NFC) 2022-07-13 23:39:33 -07:00
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
Chuanqi Xu f6b0ae144e [AST] Accept identical TypeConstraint referring to other template
parameters.

The current implementation to judge the similarity of TypeConstraint in
ASTContext::isSameTemplateParameter is problematic, it couldn't handle
the following case:

```C++
template <__integer_like _Tp, C<_Tp> Sentinel>
constexpr _Tp operator()(_Tp &&__t, Sentinel &&last) const {
    return __t;
}
```

When we see 2 such declarations from different modules, we would judge
their similarity by `ASTContext::isSame*` methods. But problems come for
the TypeConstraint. Originally, we would profile each argument one by
one. But it is not right. Since the profiling result of `_Tp` would
refer to two different template type declarations. So it would get
different results. It is right since the `_Tp` in different modules
refers to different declarations indeed. So the same declaration in
different modules would meet incorrect our-checking results.

It is not the thing we want. We want to know if the TypeConstraint have
the same expression.

Reviewer: vsapsai, ilya-biryukov

Differential Revision: https://reviews.llvm.org/D129068
2022-07-12 23:57:44 +08:00
Chuanqi Xu 4b95a5a772 [Modules] Add ODR Check for concepts
Closing https://github.com/llvm/llvm-project/issues/56310

Previously we don't check the contents of concept so it might merge
inconsistent results.

Important Note: this patch might break existing code but the behavior
might be right.

Reviewed By: erichkeane

Differential Revision: https://reviews.llvm.org/D129104
2022-07-12 23:45:53 +08:00
Jonas Devlieghere c7fd7512a5
Revert "[C++20][Modules] Update handling of implicit inlines [P1779R3]"
This reverts commit ef0fa9f0ef as a follow up to b19d3ee712 which
reverted commit ac507102d2. See https://reviews.llvm.org/D126189 for
more details.
2022-07-11 13:59:41 -07:00