[all-commits] [llvm/llvm-project] 66a357: [OpenMP] Fix releasing of stack memory

[Joachim via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 66a3575c2895f3b06056908bb40699f16e4b92d7
      https://github.com/llvm/llvm-project/commit/66a3575c2895f3b06056908bb40699f16e4b92d7
  Author: Joachim Protze <protze at itc.rwth-aachen.de>
  Date:   2020-08-14 (Fri, 14 Aug 2020)

  Changed paths:
    M openmp/runtime/src/kmp_taskdeps.cpp

  Log Message:
  -----------
  [OpenMP] Fix releasing of stack memory

Starting with 787eb0c637b I got spurious segmentation faults for some testcases. I could nail it down to `brel` trying to release the "memory" of the node allocated on the stack of __kmpc_omp_wait_deps. With this patch, you will see the assertion triggering for some of the tests in the test suite.

My proposed solution for the issue is to just patch __kmpc_omp_wait_deps:
```
  __kmp_init_node(&node);
-  node.dn.on_stack = 1;
+  // the stack owns the node
+  __kmp_node_ref(&node);
```

What do you think?

Reviewed By: AndreyChurbanov

Differential Revision: https://reviews.llvm.org/D84472