[flang] [llvm] [flang][OpenMP] Overhaul implementation of ATOMIC construct (PR #137852)

[via llvm-commits]

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@@ -1,16 +0,0 @@
-! RUN: not %flang_fc1  -fopenmp-version=51 -fopenmp %s 2>&1 | FileCheck %s
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NimishMishra wrote:

I think adding tests for unparsing would be good, since there are substantial changes to the parsing. 

https://github.com/llvm/llvm-project/pull/137852