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@cjacek cjacek commented Jun 7, 2025

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cjacek added 5 commits June 6, 2025 16:10
MSVC always emits minimal CodeView metadata with compiler information, even when
debug info is otherwise disabled. Other tools may rely on this metadata being
present. For example, linkers use it to determine whether hotpatching is enabled
for the object file.
cjacek pushed a commit that referenced this pull request Jun 7, 2025
Fixes llvm#123300

What is seen 
```
clang-repl> int x = 42;
clang-repl> auto capture = [&]() { return x * 2; };
In file included from <<< inputs >>>:1:
input_line_4:1:17: error: non-local lambda expression cannot have a capture-default
    1 | auto capture = [&]() { return x * 2; };
      |                 ^
zsh: segmentation fault  clang-repl --Xcc="-v"

(lldb) bt
* thread #1, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x8)
  * frame #0: 0x0000000107b4f8b8 libclang-cpp.19.1.dylib`clang::IncrementalParser::CleanUpPTU(clang::PartialTranslationUnit&) + 988
    frame #1: 0x0000000107b4f1b4 libclang-cpp.19.1.dylib`clang::IncrementalParser::ParseOrWrapTopLevelDecl() + 416
    frame #2: 0x0000000107b4fb94 libclang-cpp.19.1.dylib`clang::IncrementalParser::Parse(llvm::StringRef) + 612
    frame llvm#3: 0x0000000107b52fec libclang-cpp.19.1.dylib`clang::Interpreter::ParseAndExecute(llvm::StringRef, clang::Value*) + 180
    frame llvm#4: 0x0000000100003498 clang-repl`main + 3560
    frame llvm#5: 0x000000018d39a0e0 dyld`start + 2360
```

Though the error is justified, we shouldn't be interested in exiting
through a segfault in such cases.

The issue is that empty named decls weren't being taken care of
resulting into this assert


https://github.com/llvm/llvm-project/blob/c1a229252617ed58f943bf3f4698bd8204ee0f04/clang/include/clang/AST/DeclarationName.h#L503

Can also be seen when the example is attempted through xeus-cpp-lite.


![image](https://github.com/user-attachments/assets/9b0e6ead-138e-4b06-9ad9-fcb9f8d5bf6e)
cjacek pushed a commit that referenced this pull request Jun 13, 2025
…142952)

This was removed in llvm#135343 in
favour of making it a format variable, which we do here. This follows
the precedent of the `[opt]` and `[artificial]` markers.

Before:
```
 thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.2
 * frame #0: 0x000000010000037c a.out`inlined1() at inline.cpp:4:3
   frame #1: 0x000000010000037c a.out`regular() at inline.cpp:6:17
   frame #2: 0x00000001000003b8 a.out`inlined2() at inline.cpp:7:43
   frame llvm#3: 0x00000001000003b4 a.out`main at inline.cpp:10:3
   frame llvm#4: 0x0000000186345be4 dyld`start + 7040
```

After (note the `[inlined]` markers):
```
thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.2
* frame #0: 0x000000010000037c a.out`inlined1() at inline.cpp:4:3 [inlined]
  frame #1: 0x000000010000037c a.out`regular() at inline.cpp:6:17
  frame #2: 0x00000001000003b8 a.out`inlined2() at inline.cpp:7:43 [inlined]
  frame llvm#3: 0x00000001000003b4 a.out`main at inline.cpp:10:3
  frame llvm#4: 0x0000000186345be4 dyld`start + 7040
```

rdar://152642178
cjacek pushed a commit that referenced this pull request Jul 28, 2025
Tracked at llvm#112294

This patch implements from [basic.link]p14 to [basic.link]p18 partially.

The explicitly missing parts are:
- Anything related to specializations.
- Decide if a pointer is associated with a TU-local value at compile
  time.
- [basic.link]p15.1.2 to decide if a type is TU-local.
- Diagnose if TU-local functions from other TU are collected to the
  overload set. See [basic.link]p19, the call to 'h(N::A{});' in
  translation unit #2

There should be other implicitly missing parts as the wording uses
"names" briefly several times. But to implement this precisely, we have
to visit the whole AST, including Decls, Expression and Types, which may
be harder to implement and be more time-consuming for compilation time.
So I choose to implement the common parts.

It won't be too bad to miss some cases since we DIDN'T do any such
checks in the past 3 years. Any new check is an improvement. Given
modules have been basically available since clang15 without such checks,
it will be user unfriendly if we give a hard error now. And there are
a lot of cases which violating the rule actually just fine. So I decide
to emit it as warnings instead of hard errors.
cjacek pushed a commit that referenced this pull request Jul 31, 2025
Extend support in LLDB for WebAssembly. This PR adds a new Process
plugin (ProcessWasm) that extends ProcessGDBRemote for WebAssembly
targets. It adds support for WebAssembly's memory model with separate
address spaces, and the ability to fetch the call stack from the
WebAssembly runtime.

I have tested this change with the WebAssembly Micro Runtime (WAMR,
https://github.com/bytecodealliance/wasm-micro-runtime) which implements
a GDB debug stub and supports the qWasmCallStack packet.

```
(lldb) process connect --plugin wasm connect://localhost:4567
Process 1 stopped
* thread #1, name = 'nobody', stop reason = trace
    frame #0: 0x40000000000001ad
wasm32_args.wasm`main:
->  0x40000000000001ad <+3>:  global.get 0
    0x40000000000001b3 <+9>:  i32.const 16
    0x40000000000001b5 <+11>: i32.sub
    0x40000000000001b6 <+12>: local.set 0
(lldb) b add
Breakpoint 1: where = wasm32_args.wasm`add + 28 at test.c:4:12, address = 0x400000000000019c
(lldb) c
Process 1 resuming
Process 1 stopped
* thread #1, name = 'nobody', stop reason = breakpoint 1.1
    frame #0: 0x400000000000019c wasm32_args.wasm`add(a=<unavailable>, b=<unavailable>) at test.c:4:12
   1    int
   2    add(int a, int b)
   3    {
-> 4        return a + b;
   5    }
   6
   7    int
(lldb) bt
* thread #1, name = 'nobody', stop reason = breakpoint 1.1
  * frame #0: 0x400000000000019c wasm32_args.wasm`add(a=<unavailable>, b=<unavailable>) at test.c:4:12
    frame #1: 0x40000000000001e5 wasm32_args.wasm`main at test.c:12:12
    frame #2: 0x40000000000001fe wasm32_args.wasm
```

This PR is based on an unmerged patch from Paolo Severini:
https://reviews.llvm.org/D78801. I intentionally stuck to the
foundations to keep this PR small. I have more PRs in the pipeline to
support the other features/packets.

My motivation for supporting Wasm is to support debugging Swift compiled
to WebAssembly:
https://www.swift.org/documentation/articles/wasm-getting-started.html
cjacek pushed a commit that referenced this pull request Sep 24, 2025
A few improvements to logging when lldb-dap is started in **Server
Mode** AND when the **`lldb-dap.logFolder`** setting is used (not
`lldb-dap.log-path`).

### Improvement #1
**Avoid the prompt of restarting the server when starting each debug
session.**

That prompt is caused by the combination of the following facts:
1. The log filename changes every time a new debug session is starting
(see
[here](https://github.com/llvm/llvm-project/blob/9d6062c490548a5e6fea103e010ab3c9bc73a86d/lldb/tools/lldb-dap/src-ts/logging.ts#L47))
2. The log filename is passed to the server via an environment variable
called "LLDBDAP_LOG" (see
[here](https://github.com/llvm/llvm-project/blob/9d6062c490548a5e6fea103e010ab3c9bc73a86d/lldb/tools/lldb-dap/src-ts/debug-adapter-factory.ts#L263-L269))
3. All environment variables are put into the "spawn info" variable (see
[here](https://github.com/llvm/llvm-project/blob/9d6062c490548a5e6fea103e010ab3c9bc73a86d/lldb/tools/lldb-dap/src-ts/lldb-dap-server.ts#L170-L172)).
4. The old and new "spawn info" are compared to decide if a prompt
should show (see
[here](https://github.com/llvm/llvm-project/blob/9d6062c490548a5e6fea103e010ab3c9bc73a86d/lldb/tools/lldb-dap/src-ts/lldb-dap-server.ts#L107-L110)).

The fix is to remove the "LLDBDAP_LOG" from the "spawn info" variable,
so that the same server can be reused if the log path is the only thing
that has changed.

### Improvement #2
**Avoid log file conflict when multiple users share a machine and start
server in the same second.**

The problem: If two users start lldb-dap server in the same second, they
will share the same log path. The first user will create the log file.
The second user will find that they cannot access the same file, so
their server will fail to start.

The fix is to add a part of the VS Code session ID to the log filename.

### Improvement llvm#3
**Avoid restarting the server when the order of environment variables
changed.**

This is done by sorting the environment variables before putting them
into the "spawn info".
cjacek pushed a commit that referenced this pull request Sep 24, 2025
Need this as `mlir/dialects/transform/smt.py` imports it:

```py
from .._transform_smt_extension_ops_gen import *
from .._transform_smt_extension_ops_gen import _Dialect
```
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