[llvm] [openmp] [OpenMP][Offload] Add `LIBOMPTARGET_TREAT_ATTACH_AUTO_AS_ALWAYS` to treat `attach(auto)` as `attach(always)`. (PR #172382)

[Abhinav Gaba via llvm-commits]

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@@ -33,6 +33,10 @@ class MappingConfig {
   MappingConfig() {
     BoolEnvar ForceAtomic = BoolEnvar("LIBOMPTARGET_MAP_FORCE_ATOMIC", true);
     UseEventsForAtomicTransfers = ForceAtomic;
+
+    BoolEnvar TreatAttachAutoAsAlwaysEnvar(
+        "LIBOMPTARGET_TREAT_ATTACH_AUTO_AS_ALWAYS", false);
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abhinavgaba wrote:

We can rename this to LIBOMPTARGET_ATTACH_FORCE_ALWAYS to align with the above, if that's preferable. That is shorter, but maybe not as clear.

https://github.com/llvm/llvm-project/pull/172382