[qt/clang/llvm-project]: Summary of bulk changes made

Git repository change summary for qt/clang/llvm-project
Pushed by mirror-service into branch 'upstream/users/cchen/flang-metadirective-loop-core'.
Changed from 982040d69a8674b0d47d2ef91c938deb0de4770b to fc66b7abc2f318799acdd6101f694ad28e413a38
Acknowledgement was received that this change introduces only existing code that has been pushed to another public open source repository.

This change contains the following new commits:

Git commit 83ba8addf60668a971453eed207f9bfdaa379f97 by GitHub (on behalf of Andrew Haberlandt) on 20/07/2026 at 17:18..
[compiler-rt] Move sanitizer ignorelists to sanitizer-ignorelists target (#200518)

This adds a `sanitizer-ignorelists` target to compiler-rt, allowing the
ignorelists to be built independently of the sanitizer runtimes. The
ignorelists are still built by default, but this change is not quite
NFC: when any of the sanitizers are built, all of the ignorelists will
be included (rather than the individual runtime ignorelists being built
with their respective runtimes).

For _why_ we want to be able to build these independently of the
runtimes, see
https://github.com/llvm/llvm-project/pull/195690#issuecomment-4384573223

I did not move the dfsan abilist to this new target because it is not as
straightforward as a copying a static file.

Assisted-by: Claude

rdar://175962064
https://invent.kde.org/qt/clang/llvm-project/-/commit/83ba8addf60668a971453eed207f9bfdaa379f97

Git commit d2e70aa7e546f7f2bbcf398b42151e464ce1098e by GitHub (on behalf of Alex Langford) on 20/07/2026 at 17:29..
[lldb] Remove unused method DynamicLoaderDarwin::ImageInfo::FindSegment (#210155)

This method is unused.
https://invent.kde.org/qt/clang/llvm-project/-/commit/d2e70aa7e546f7f2bbcf398b42151e464ce1098e

Git commit b559a53427f926a603a1755f60d98e06e2b7e1d2 by GitHub (on behalf of A. Jiang) on 20/07/2026 at 17:29..
[libc++][docs] Avoid talking about other implementations on DR status (#210637)

Standard library implementations consistently treat (or will
consistently treat) some LWG papers as Defect Reports that are also
applied to old modes, despite that they are not officially listed as
Defect Reports in WG21 meeting minutes. We used to say "other
implementations (namely MSVC STL and libstdc++) will do the same" for
some of them.

However, such sentences will become outdated soon when other
implementations actually do so. It is possibly better to avoid saying
so, which potentially requires synchronizing our documentation with
other implementations.
https://invent.kde.org/qt/clang/llvm-project/-/commit/b559a53427f926a603a1755f60d98e06e2b7e1d2

Git commit 3b80cd45daebaa1a898aed97356f8810e954c52f by chichunchen on 20/07/2026 at 17:33..
[flang][OpenMP] Check DEFAULT(NONE) on metadirective loop variants

Flang does not enforce `DEFAULT(NONE)` for variables referenced in a loop
associated with a standalone METADIRECTIVE. Consequently, it accepts invalid
programs when a potentially selectable loop variant specifies DEFAULT(NONE) but
omits a referenced variable from its data-sharing clauses. This change checks the
associated loop for each potentially selectable `DEFAULT(NONE)` variant and
diagnoses missing data-sharing attributes as it does for ordinary OpenMP loop
constructs.

Standalone metadirectives and their associated loops are separate parse-tree
nodes. For example:

```fortran
!$omp metadirective &
!$omp& when(implementation={vendor(llvm)}: &
!$omp& parallel do default(none) shared(n, a)) default(nothing)
do i = 1, n
  a(i) = x
end do
```

Unlike an ordinary `PARALLEL DO`, the loop is not nested under the directive:

```text
METADIRECTIVE
`-- WHEN
    `-- PARALLEL DO DEFAULT(NONE) SHARED(n, a)

DO
`-- a(i) = x
```

Name resolution therefore leaves the variant context before visiting the loop and
does not diagnose the missing data-sharing attribute for `x`.

After associating a metadirective with its loop, validate DEFAULT(NONE) for each
potentially selectable loop variant. Preserve the existing rules for
predetermined and explicit data-sharing attributes, static locals, nested
constructs, specification expressions, and statically inapplicable variants.

Assisted with codex.
https://invent.kde.org/qt/clang/llvm-project/-/commit/3b80cd45daebaa1a898aed97356f8810e954c52f

Git commit 07b8789cd5fcf088abc181f79e57bcdf638ae599 by chichunchen (on behalf of Chi Chun, Chen) on 20/07/2026 at 18:33..
[flang][OpenMP] Lower ordinary loop variants in metadirectives

Add core lowering for ordinary DO, SIMD, and DO SIMD replacements
selected by a metadirective. Support standalone and begin/end forms with
static or runtime selection, while deferring replacements that require
data-environment reconstruction.

Preserve sequential fallbacks, code after associated loops, compiler
loop directives, and alternate ENTRY control flow. Apply loop-index
data-sharing attributes per selected variant without leaking them to
other arms.

Keep focused TODOs for pointer and allocatable loop indices,
data-environment and data-sharing variants, body- and
loop-sequence-associated variants, and TARGET.

Add lowering tests for selection, association, fallbacks, affected loop
depth, compiler directives, ENTRY points, and unsupported boundaries.

Assisted with codex.
https://invent.kde.org/qt/clang/llvm-project/-/commit/07b8789cd5fcf088abc181f79e57bcdf638ae599

Git commit 57bd645f1833a13f8500fe106d3a484823e7991d by chichunchen on 20/07/2026 at 18:33..
Restrict metadirective loop lowering to safe cases

Defer loop variants nested in an existing OpenMP data environment until lowering
can create a variant-local loop induction variable binding. This prevents variant
DSA from affecting the enclosing construct, including for statically inapplicable
variants.

Limit core lowering to DO, SIMD, and DO SIMD. Emit focused TODOs for other
loop-associated directives and add coverage for both boundaries.

Assisted with codex.
https://invent.kde.org/qt/clang/llvm-project/-/commit/57bd645f1833a13f8500fe106d3a484823e7991d

Git commit 309df8e5a0b64602998da9c7dfb1060dc3268683 by chichunchen on 20/07/2026 at 18:33..
Avoid lowering clauses for inapplicable metadirective variants

Classify raw directive specifications from their leaf directive IDs when
checking for loop association. This keeps clause conversion after applicability
filtering, so unsupported clauses in discarded variants cannot reach lowering.

Add a regression for an inapplicable ASSUME HOLDS variant with a NOTHING fallback.

Assisted with codex.
https://invent.kde.org/qt/clang/llvm-project/-/commit/309df8e5a0b64602998da9c7dfb1060dc3268683

Git commit 742a2dd63b0bdd381ca76b4ae31c133178d5d7b2 by chichunchen on 20/07/2026 at 20:37..
Fix metadirective loop variant safety checks

Classify candidate and fallback association from raw directive IDs so clauses are
only converted for the selected variant.

Recognize data environments selected by enclosing metadirectives from the emitted
OpenMP operation ancestry. Add regressions for unselected clauses and nested
selected parallel regions.

Assisted with codex.
https://invent.kde.org/qt/clang/llvm-project/-/commit/742a2dd63b0bdd381ca76b4ae31c133178d5d7b2

Git commit fc66b7abc2f318799acdd6101f694ad28e413a38 by chichunchen on 20/07/2026 at 20:37..
Reject unsafe metadirective loop lowering cases

Prevent metadirective loop lowering from crashing or producing invalid IR for
unsupported induction-variable and control-flow shapes.

Defer ASSOCIATE-name induction variables, unstructured associated loops, and
unstructured begin/end continuations with focused diagnostics.
Use conforming begin/end syntax for the body-associated variant regression.

Assisted with codex.
https://invent.kde.org/qt/clang/llvm-project/-/commit/fc66b7abc2f318799acdd6101f694ad28e413a38