[all-commits] [llvm/llvm-project] 1c2e7d: [MS] Fix crash involving gnu stmt exprs and inalloca

[Reid Kleckner via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 1c2e7d200df27e91631ba300965245518bfe252c
      https://github.com/llvm/llvm-project/commit/1c2e7d200df27e91631ba300965245518bfe252c
  Author: Reid Kleckner <rnk at google.com>
  Date:   2021-03-04 (Thu, 04 Mar 2021)

  Changed paths:
    M clang/lib/CodeGen/CGCall.cpp
    M clang/lib/CodeGen/CodeGenFunction.cpp
    M clang/lib/CodeGen/CodeGenFunction.h
    A clang/test/CodeGenCXX/inalloca-stmtexpr.cpp

  Log Message:
  -----------
  [MS] Fix crash involving gnu stmt exprs and inalloca

Use a WeakTrackingVH to cope with the stmt emission logic that cleans up
unreachable blocks. This invalidates the reference to the deferred
replacement placeholder. Cope with it.

Fixes PR25102 (from 2015!)