Assertion failure in PopCleanupBlock compiling catch block

[VoxSciurorum]

Assertion failure with attached reproducer:

Assertion failed: (!EHStack.empty() && "cleanup stack is empty!"), function PopCleanupBlock, file /data/Cilk/opencilk-project/clang/lib/CodeGen/CGCleanup.cpp, line 670.

If I remove the _Cilk_sync in the catch block the program compiles but crashes at runtime if an exception is thrown.
grain-eea328.cpp.txt
grain-eea328.sh.txt

[VoxSciurorum]

Simpler test case:

extern int f();

void g() {
  try {
    f();
  } catch (int x) {
    _Cilk_sync;
  }
}

Compile with clang++ -O1.

[VoxSciurorum]

TaskFrameScope::TaskFrameScope pushes a cleanup if CGF.CurSyncRegion is not null. TaskFrameScope::~TaskFrameScope pops a cleanup if CGF.CurSyncRegion is not null. But CGF.CurSyncRegion has changed from null to non-null between construction and destruction. Should the destructor be testing TaskFrame instead of CGF.CurSyncRegion so it pops a cleanup only if one was pushed?

[neboat]

Yes, that change sounds good to me.

I also managed to reproduce the runtime crash you encountered with the original test case. I'm looking into that crash.