[all-commits] [llvm/llvm-project] 1fad78: [Clang][Coroutines] Properly emit EH code for init...

[Yuxuan Chen via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 1fad78b123d20db675d339053e4265aceb07c4af
      https://github.com/llvm/llvm-project/commit/1fad78b123d20db675d339053e4265aceb07c4af
  Author: Yuxuan Chen <yuxuanchen1997 at outlook.com>
  Date:   2023-11-21 (Tue, 21 Nov 2023)

  Changed paths:
    M clang/docs/ReleaseNotes.rst
    M clang/lib/CodeGen/CGCoroutine.cpp
    A clang/test/CodeGenCoroutines/coro-init-await-nontrivial-return.cpp

  Log Message:
  -----------
  [Clang][Coroutines] Properly emit EH code for initial suspend `await_resume`  (#73073)

This change aims to fix an ICE in issue
https://github.com/llvm/llvm-project/issues/63803

The crash happens in `ExitCXXTryStmt` because `EmitAnyExpr()` adds
additional cleanup to the `EHScopeStack`. This messes up the assumption
in `ExitCXXTryStmt` that the top of the stack should be a
`EHCatchScope`.

However, since we never read a value returned from `await_resume()` of
an init suspend, we can skip the part that builds this `RValue`.

The code here may not be in the best shape. There's another bug that
`memberCallExpressionCanThrow` doesn't work on the current Expr due to
type mismatch. I am preparing a separate PR to address it plus some
refactoring might be beneficial.