Commit Graph

1602 Commits

Author SHA1 Message Date
Jonathan Camilleri 4cd7529e4c [clang][DebugInfo] Emit access specifiers for typedefs
The accessibility level of a typedef or using declaration in a
struct or class was being lost when producing debug information.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D134339
2022-09-22 17:08:41 +00:00
Matheus Izvekov f4ea3bd4b2
[clang] Fixes how we represent / emulate builtin templates
We change the template specialization of builtin templates to
behave like aliases.

Though unlike real alias templates, these might still produce a canonical
TemplateSpecializationType when some important argument is dependent.

For example, we can't do anything about make_integer_seq when the
count is dependent, or a type_pack_element when the index is dependent.

We change type deduction to not try to deduce canonical TSTs of
builtin templates.

We also change those buitin templates to produce substitution sugar,
just like a real instantiation would, making the resulting type correctly
represent the template arguments used to specialize the underlying template.

And make_integer_seq will now produce a TST for the specialization
of it's first argument, which we use as the underlying type of
the builtin alias.

When performing member access on the resulting type, it's now
possible to map from a Subst* node to the template argument
as-written used in a regular fashion, without special casing.

And this fixes a bunch of bugs with relation to these builtin
templates factoring into deduction.

Fixes GH42102 and GH51928.

Depends on D133261

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

Differential Revision: https://reviews.llvm.org/D133262
2022-09-16 17:44:12 +02:00
Kazu Hirata b7a7aeee90 [clang] Qualify auto in range-based for loops (NFC) 2022-09-03 23:27:27 -07:00
Luke Nihlen c9aba60074 [clang] Don't emit debug vtable information for consteval functions
Fixes https://github.com/llvm/llvm-project/issues/55065

Reviewed By: shafik

Differential Revision: https://reviews.llvm.org/D132874
2022-08-30 19:10:15 +00:00
David Blaikie 06c70e9b99 DebugInfo: Remove auto return type representation support
Seems this complicated lldb sufficiently for some cases that it hasn't
been worth supporting/fixing there - and it so far hasn't provided any
new use cases/value for debug info consumers, so let's remove it until
someone has a use case for it.

(side note: the original implementation of this still had a bug (I
should've caught it in review) that we still didn't produce
auto-returning function declarations in types where the function wasn't
instantiatied (that requires a fix to remove the `if
getContainedAutoType` condition in
`CGDebugInfo::CollectCXXMemberFunctions` - without that, auto returning
functions were still being handled the same as member function templates
and special member functions - never added to the member list, only
attached to the type via the declaration chain from the definition)

Further discussion about this in D123319

This reverts commit 5ff992bca208a0e37ca6338fc735aec6aa848b72: [DEBUG-INFO] Change how we handle auto return types for lambda operator() to be consistent with gcc

This reverts commit c83602fdf51b2692e3bacb06bf861f20f74e987f: [DWARF5][clang]: Added support for DebugInfo generation for auto return type for C++ member functions.

Differential Revision: https://reviews.llvm.org/D131933
2022-08-17 00:35:05 +00:00
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
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
Alok Kumar Sharma 5ec6ea3dfd [clang][OpenMP][DebugInfo] Mark OpenMP generated functions as artificial
The Clang compiler generates internal functions for OpenMP. Current
patch marks these functions as artificial.

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D111521
2022-08-02 21:24:46 +05:30
David Blaikie 4e719e0f16 DebugInfo: Prefer vtable homing over ctor homing.
Vtables will be emitted in fewer places than ctors (every ctor
references the vtable, so at worst it's the same places - but at best
the type has a non-inline key function and the vtable is emitted in one
place)

Pulling this fix out of 517bbc64db which
was reverted in 4821508d4d
2022-07-28 00:07:35 +00:00
Argyrios Kyrtzidis 8dfaecc4c2 [CGDebugInfo] Access the current working directory from the `VFS`
...instead of calling `llvm::sys::fs::current_path()` directly.

Differential Revision: https://reviews.llvm.org/D130443
2022-07-26 13:48:39 -07:00
David Blaikie 4821508d4d Revert "DebugInfo: Fully integrate ctor type homing into 'limited' debug info"
Reverting to simplify some Google-internal rollout issues. Will recommit
in a week or two.

This reverts commit 517bbc64db.
2022-06-24 17:07:47 +00:00
David Blaikie 517bbc64db DebugInfo: Fully integrate ctor type homing into 'limited' debug info
Simplify debug info back to just "limited" or "full" by rolling the ctor
type homing fully into the "limited" debug info.

Also fix a bug I found along the way that was causing ctor type homing
to kick in even when something could be vtable homed (where vtable
homing is stronger/more effective than ctor homing) - fixing at the same
time as it keeps the tests (that were testing only "limited non ctor"
homing and now test ctor homing) passing.
2022-06-23 20:15:00 +00:00
Kazu Hirata ca4af13e48 [clang] Don't use Optional::getValue (NFC) 2022-06-20 22:59:26 -07:00
Jon Chesterfield 83c431fb9e [amdgpu] Add amdgpu_kernel calling conv attribute to clang
Allows emitting define amdgpu_kernel void @func() IR from C or C++.

This replaces the current workflow which is to write a stub in opencl that
calls an external C function implemented in C++ combined through llvm-link.

Calling the resulting function still requires a manual implementation of the
ABI from the host side. The primary application is for more rapid debugging
of the amdgpu backend by permuting a C or C++ test file instead of manually
updating an IR file.

Implementation closely follows D54425. Non-amd reviewers from there.

Reviewed By: yaxunl

Differential Revision: https://reviews.llvm.org/D125970
2022-05-20 08:50:37 +01:00
Mitch Phillips 7aa1fa0a0a Reland "[dwarf] Emit a DIGlobalVariable for constant strings."
An upcoming patch will extend llvm-symbolizer to provide the source line
information for global variables. The goal is to move AddressSanitizer
off of internal debug info for symbolization onto the DWARF standard
(and doing a clean-up in the process). Currently, ASan reports the line
information for constant strings if a memory safety bug happens around
them. We want to keep this behaviour, so we need to emit debuginfo for
these variables as well.

Reviewed By: dblaikie, rnk, aprantl

Differential Revision: https://reviews.llvm.org/D123534
2022-05-18 13:56:45 -07:00
Mitch Phillips ed2c3218f5 Revert "[dwarf] Emit a DIGlobalVariable for constant strings."
This reverts commit 4680982b36.

Broke a fuchsia windows bot. More details in the review:
https://reviews.llvm.org/D123534
2022-05-16 19:07:38 -07:00
Mitch Phillips 4680982b36 [dwarf] Emit a DIGlobalVariable for constant strings.
An upcoming patch will extend llvm-symbolizer to provide the source line
information for global variables. The goal is to move AddressSanitizer
off of internal debug info for symbolization onto the DWARF standard
(and doing a clean-up in the process). Currently, ASan reports the line
information for constant strings if a memory safety bug happens around
them. We want to keep this behaviour, so we need to emit debuginfo for
these variables as well.

Reviewed By: dblaikie, rnk, aprantl

Differential Revision: https://reviews.llvm.org/D123534
2022-05-16 16:52:16 -07:00
Matt Devereau 75bb815231 [AArch64][SVE] Add aarch64_sve_pcs attribute to Clang
Enable function attribute aarch64_sve_pcs at the C level, which correspondes to
aarch64_sve_vector_pcs at the LLVM IR level.

This requirement was created by this addition to the ARM C Language Extension:
https://github.com/ARM-software/acle/pull/194

Differential Revision: https://reviews.llvm.org/D124998
2022-05-11 13:33:56 +00:00
Ying Yi b09ba42620 Bug 51277: [DWARF] DW_AT_alignment incorrect when
attribute((__aligned__)) is present but ignored`

In the original code, the 'getDeclAlignIfRequired' function is used.
The 'getDeclAlignIfRequired' function will return the max alignment
of all aligned attributes if the type has aligned attributes. The
function doesn't consider the type at all.

The 'getTypeAlignIfRequired' function uses the type's alignment value,
which also used by the 'alignof' function. I think we should use the
function of 'getTypeAlignIfRequired'.

Reviewed By: dblaikie, jmorse, wolfgangp

Differential Revision: https://reviews.llvm.org/D124006
2022-04-22 12:15:00 +01:00
Shafik Yaghmour 5ff992bca2 [DEBUG-INFO] Change how we handle auto return types for lambda operator() to be consistent with gcc
D70524 added support for auto return types for C++ member functions. I was
implementing support on the LLDB side for looking up the deduced type.

I ran into trouble with some cases with respect to lambdas. I looked into
how gcc was handling these cases and it appears gcc emits the deduced return type for lambdas.

So I am changing out behavior to match that.

Differential Revision: https://reviews.llvm.org/D123319
2022-04-21 14:58:50 -07:00
Jan Svoboda 9d98f58959 [clang][CodeGen] NFCI: Use FileEntryRef
This patch removes use of the deprecated `DirectoryEntry::getName()` from clangCodeGen by using `{File,Directory}EntryRef` instead.

Reviewed By: bnbarham

Differential Revision: https://reviews.llvm.org/D123768
2022-04-15 15:16:17 +02:00
David Blaikie 1cee3d9db7 DebugInfo: Consider the type of NTTP when simplifying template names
Since the NTTP may need to be cast to the type when rebuilding the name,
check that the type can be rebuilt when determining whether a template
name can be simplified.
2022-04-08 00:00:46 +00:00
Kavitha Natarajan b1ea0191a4 [clang][DebugInfo] Support debug info for alias variable
clang to emit DWARF information for global alias variable as
DW_TAG_imported_declaration. This change also handles nested
(recursive) imported declarations.

Reviewed by: dblaikie, aprantl

Differential Revision: https://reviews.llvm.org/D120989
2022-04-07 17:15:40 +05:30
David Blaikie 6b306233f7 DebugInfo: Make the simplified template names prefix more unique 2022-04-06 18:25:46 +00:00
David Blaikie bb3980ae9f DebugInfo: Don't use enumerators in template names for debug info as they are not canonical
Since enumerators may not be available in every translation unit they
can't be reliably used to name entities. (this also makes simplified
template name roundtripping infeasible - since the expected name could
only be rebuilt if the enumeration definition could be found (or only if
it couldn't be found, depending on the context of the original name))
2022-04-05 17:16:42 +00:00
David Blaikie 7b498beef0 DebugInfo: Classify noreturn function types as non-reconstructible
This information isn't preserved in the DWARF description of function
types (though probably should be - it's preserved on the function
declarations/definitions themselves through the DW_AT_noreturn attribute
- but we should move or also include that in the subroutine type itself
too - but for now, with it not being there, the DWARF is lossy and
can't be reconstructed)
2022-03-24 18:53:14 +00:00
Yonghong Song 3251ba2d0f [Attr] Fix a btf_type_tag AST generation
Current ASTContext.getAttributedType() takes attribute kind,
ModifiedType and EquivType as the hash to decide whether an AST node
has been generated or note. But this is not enough for btf_type_tag
as the attribute might have the same ModifiedType and EquivType, but
still have different string associated with attribute.

For example, for a data structure like below,
  struct map_value {
        int __attribute__((btf_type_tag("tag1"))) __attribute__((btf_type_tag("tag3"))) *a;
        int __attribute__((btf_type_tag("tag2"))) __attribute__((btf_type_tag("tag4"))) *b;
  };
The current ASTContext.getAttributedType() will produce
an AST similar to below:
  struct map_value {
        int __attribute__((btf_type_tag("tag1"))) __attribute__((btf_type_tag("tag3"))) *a;
        int __attribute__((btf_type_tag("tag1"))) __attribute__((btf_type_tag("tag3"))) *b;
  };
and this is incorrect.

It is very difficult to use the current AttributedType as it is hard to
get the tag information. To fix the problem, this patch introduced
BTFTagAttributedType which is similar to AttributedType
in many ways but with an additional BTFTypeTagAttr. The tag itself can
be retrieved with BTFTypeTagAttr.
With the new BTFTagAttributed type, the debuginfo code can be greatly
simplified compared to previous TypeLoc based approach.

Differential Revision: https://reviews.llvm.org/D120296
2022-03-16 08:46:52 -07:00
Simon Moll 0aab344104 [Clang] Allow "ext_vector_type" applied to Booleans
This is the `ext_vector_type` alternative to D81083.

This patch extends Clang to allow 'bool' as a valid vector element type
(attribute ext_vector_type) in C/C++.

This is intended as the canonical type for SIMD masks and facilitates
clean vector intrinsic declarations.  Vectors of i1 are supported on IR
level and below down to many SIMD ISAs, such as AVX512, ARM SVE (fixed
vector length) and the VE target (NEC SX-Aurora TSUBASA).

The RFC on cfe-dev: https://lists.llvm.org/pipermail/cfe-dev/2020-May/065434.html

Reviewed By: erichkeane

Differential Revision: https://reviews.llvm.org/D88905
2022-03-16 11:10:32 +01:00
Keith Smiley a2db7d5e9c reland: [clang] Don't append the working directory to absolute paths
This fixes a bug that happens when using -fdebug-prefix-map to remap an
absolute path to a relative path. Since the path was absolute before
remapping, it is safe to assume that concatenating the remapped working
directory would be wrong.

This was originally submitted as https://reviews.llvm.org/D113718, but
reverted because when testing with dwarf 5 enabled, the tests were too
strict.

Differential Revision: https://reviews.llvm.org/D121663
2022-03-15 13:42:35 -07:00
Keith Smiley cb22d71806 [clang] Fix DIFile directory root on Windows
On unix systems this logic would not separate the file and directory of
the DIFile unless they shared more components at the start than just the
root path character. The logic to do this was unix specific so it didn't
work on Windows. Now we check if the entire root_path is the same as
what you were going to set as the Dir and use the full filepath in that
case.

Differential Revision: https://reviews.llvm.org/D111579
2022-03-14 20:07:01 -07:00
Adrian Prantl bc7aeea854 Revert "Don't append the working directory to absolute paths"
This reverts commit 2cd9a86da5.
2022-02-25 17:00:10 -08:00
Adrian Prantl 2cd9a86da5 Don't append the working directory to absolute paths
This fixes a bug that happens when using -fdebug-prefix-map to remap
an absolute path to a relative path. Since the path was absolute
before remapping, it is safe to assume that concatenating the remapped
working directory would be wrong.

Differential Revision: https://reviews.llvm.org/D113718
2022-02-25 13:03:59 -08:00
Shafik Yaghmour f56cb520d8 [DEBUGINFO] [LLDB] Add support for generating debug-info for structured bindings of structs and arrays
Currently we are not emitting debug-info for all cases of structured bindings a
C++17 feature which allows us to bind names to subobjects in an initializer.

A structured binding is represented by a DecompositionDecl AST node and the
binding are represented by a BindingDecl. It looks the original implementation
only covered the tuple like case which be represented by a DeclRefExpr which
contains a VarDecl.

If the binding is to a subobject of the struct the binding will contain a
MemberExpr and in the case of arrays it will contain an ArraySubscriptExpr.
This PR adds support emitting debug-info for the MemberExpr and ArraySubscriptExpr
cases as well as llvm and lldb tests for these cases as well as the tuple case.

Differential Revision: https://reviews.llvm.org/D119178
2022-02-17 11:14:14 -08:00
Simon Pilgrim 57fc9798d7 [clang] CGDebugInfo::getOrCreateMethodType - use castAs<> instead of getAs<> to avoid dereference of nullptr
The pointer is always dereferenced, so assert the cast is correct instead of returning nullptr
2022-02-17 13:18:23 +00:00
David Blaikie 9980a3f831 DebugInfo: Disable simplified template names for -gmlt and below
Since -gmlt doesn't carry any type information necessary to rebuild
template names.
2022-02-15 11:58:40 -08:00
David Blaikie 1ea326634b DebugInfo: Don't simplify template names using _BitInt(N)
_BitInt(N) only encodes the byte size in DWARF, not the bit size, so
can't be reconstituted.
2022-02-15 11:58:40 -08:00
David Blaikie 389f67b35b DebugInfo: Don't simplify names referencing local enums
Due to the way type units work, this would lead to a declaration in a
type unit of a local type in a CU - which is ambiguous. Rather than
trying to resolve that relative to the CU that references the type unit,
let's just not try to simplify these names.

Longer term this should be fixed by not putting the template
instantiation in a type unit to begin with - since it references an
internal linkage type, it can't legitimately be duplicated/in more than
one translation unit, so skip the type unit overhead. (but the right fix
for that is to move type unit management into a DICompositeType flag
(dropping the "identifier" field is not a perfect solution since it
breaks LLVM IR linking decl/def merging during IR linking))
2022-02-10 15:51:47 -08:00
David Blaikie 26c5cf8fa0 Fix Windows build that fails if a class has a member with the same naem 2022-02-10 15:27:31 -08:00
David Blaikie f3a2cfc103 DebugInfo: Don't simplify any template referencing a lambda
Lambda names aren't entirely canonical (as demonstrated by the
cross-project-test added here) at the moment (we should fix that for a
bunch of reasons) - even if the template referencing them is
non-simplified, other names referencing /that/ template can't be
simplified either because type units might cause a different template to
be picked up that would conflict with the expected name.

(other than for roundtripping precision, it'd be OK to simplify types
that reference types that reference lambdas - but best be consistent
between the roundtrip/verify mode and the actual simplified template
names mode)
2022-02-10 14:56:54 -08:00
Hans Wennborg 0b48d0fe12 [ADT] Add an in-place version of toHex()
and use that to simplify MD5's hex string code which was previously
using a string stream, as well as Clang's
CGDebugInfo::computeChecksum().

Differential revision: https://reviews.llvm.org/D116960
2022-01-11 11:51:04 +01:00
Kazu Hirata 40446663c7 [clang] Use true/false instead of 1/0 (NFC)
Identified with modernize-use-bool-literals.
2022-01-09 00:19:47 -08:00
Shao-Ce SUN ec501f15a8 [clang][CodeGen] Remove the signed version of createExpression
Fix a TODO. Remove the callers of this signed version and delete.

Reviewed By: CodaFi

Differential Revision: https://reviews.llvm.org/D116014
2021-12-27 14:16:08 +08:00
Sam McCall af27466c50 Reland "[AST] Add UsingType: a sugar type for types found via UsingDecl"
This reverts commit cc56c66f27.
Fixed a bad assertion, the target of a UsingShadowDecl must not have
*local* qualifiers, but it can be a typedef whose underlying type is qualified.
2021-12-20 18:03:15 +01:00
Sam McCall cc56c66f27 Revert "[AST] Add UsingType: a sugar type for types found via UsingDecl"
This reverts commit e1600db19d.

Breaks sanitizer tests, at least on windows:
https://lab.llvm.org/buildbot/#/builders/127/builds/21592/steps/4/logs/stdio
2021-12-20 17:53:56 +01:00
Sam McCall e1600db19d [AST] Add UsingType: a sugar type for types found via UsingDecl
Currently there's no way to find the UsingDecl that a typeloc found its
underlying type through. Compare to DeclRefExpr::getFoundDecl().

Design decisions:
- a sugar type, as there are many contexts this type of use may appear in
- UsingType is a leaf like TypedefType, the underlying type has no TypeLoc
- not unified with UnresolvedUsingType: a single name is appealing,
  but being sometimes-sugar is often fiddly.
- not unified with TypedefType: the UsingShadowDecl is not a TypedefNameDecl or
  even a TypeDecl, and users think of these differently.
- does not cover other rarer aliases like objc @compatibility_alias,
  in order to be have a concrete API that's easy to understand.
- implicitly desugared by the hasDeclaration ASTMatcher, to avoid
  breaking existing patterns and following the precedent of ElaboratedType.

Scope:
- This does not cover types associated with template names introduced by
  using declarations. A future patch should introduce a sugar TemplateName
  variant for this. (CTAD deduced types fall under this)
- There are enough AST matchers to fix the in-tree clang-tidy tests and
  probably any other matchers, though more may be useful later.

Caveats:
- This changes a fairly common pattern in the AST people may depend on matching.
  Previously, typeLoc(loc(recordType())) matched whether a struct was
  referred to by its original scope or introduced via using-decl.
  Now, the using-decl case is not matched, and needs a separate matcher.
  This is similar to the case of typedefs but nevertheless both adds
  complexity and breaks existing code.

Differential Revision: https://reviews.llvm.org/D114251
2021-12-20 17:15:38 +01:00
jacquesguan 9c11e95286 [Clang][RISCV] Fix upper bound of RISC-V V type in debug info
The UpperBound of RVV type in debug info should be elements count minus one,
as the LowerBound start from zero.

Reviewed By: HsiangKai

Differential Revision: https://reviews.llvm.org/D115430
2021-12-20 14:25:06 +08:00
Esme-Yi 18f087c21c [DebugInfo][Clang] record the access flag for class/struct/union types.
Summary: This patch records the access flag for
class/struct/union types in the clang part.

The summary of binary size change and debug info size change due to the DW_AT_accessibility attribute are as the following table. They are built with flags of `clang -O0 -g` (no -gz).

| section | before | after | change | % |
| .debug_loc | 929821 | 929821 |0|0|
|.debug_abbrev | 5885289 | 5971547 |+86258|+1.466%|
|.debug_info | 497613455 | 498122074 |+508619|+0.102%|
|.debug_ranges | 45731664 | 45731664 |0|0|
|.debug_str | 233842595 | 233839388 |-3207| -0.001%|
|.debug_line | 149773166 | 149764583 |-8583|-0.006%|
|total (debug) |933775990 |934359077|+583087 |+0.062%|

|total (binary) |1394617288 | 1395200024| +582736|+0.042%|

Reviewed By: dblaikie, shchenz

Differential Revision: https://reviews.llvm.org/D115503
2021-12-20 02:40:42 +00:00
Aaron Ballman 6c75ab5f66 Introduce _BitInt, deprecate _ExtInt
WG14 adopted the _ExtInt feature from Clang for C23, but renamed the
type to be _BitInt. This patch does the vast majority of the work to
rename _ExtInt to _BitInt, which accounts for most of its size. The new
type is exposed in older C modes and all C++ modes as a conforming
extension. However, there are functional changes worth calling out:

* Deprecates _ExtInt with a fix-it to help users migrate to _BitInt.
* Updates the mangling for the type.
* Updates the documentation and adds a release note to warn users what
is going on.
* Adds new diagnostics for use of _BitInt to call out when it's used as
a Clang extension or as a pre-C23 compatibility concern.
* Adds new tests for the new diagnostic behaviors.

I want to call out the ABI break specifically. We do not believe that
this break will cause a significant imposition for early adopters of
the feature, and so this is being done as a full break. If it turns out
there are critical uses where recompilation is not an option for some
reason, we can consider using ABI tags to ease the transition.
2021-12-06 12:52:01 -05:00