[flang-commits] [flang] [flang][OpenMP] Diagnose privatized array section reductions (PR #215997)

[via flang-commits]

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@@ -4922,14 +4919,16 @@ static mlir::omp::TaskloopContextOp genStandaloneTaskloop(
                            enableDelayedPrivatization, symTable);
   dsp.processStep1(&taskloopClauseOps);
 
-  if (hasPrivatizedArrayElementReduction(inReductionObjects,
-                                         dsp.getAllSymbolsToPrivatize()))
-    TODO(loc, "TASKLOOP construct with IN_REDUCTION of an array element whose "
-              "base array is privatized");
-  if (hasPrivatizedArrayElementReduction(reductionObjects,
-                                         dsp.getAllSymbolsToPrivatize()))
-    TODO(loc, "TASKLOOP construct with REDUCTION of an array element whose "
-              "base array is privatized");
+  if (hasPrivatizedArrayReductionObject(inReductionObjects,
+                                        dsp.getDelayedPrivSymbols()))
+    TODO(loc,
+         "TASKLOOP construct with IN_REDUCTION of an array element or section "
+         "whose base array is privatized");
+  if (hasPrivatizedArrayReductionObject(reductionObjects,
+                                        dsp.getDelayedPrivSymbols()))
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MattPD wrote:

The eager array-element diagnostic now covers the original regression.

Eager array sections retain a pre-existing storage-binding problem. With `reduction(+: a(2:3))` and a loop-body read of `a(1)`, the firstprivate clone is dead, and `a(1)` reads the zero-initialized reduction box.

Could eager array sections remain under the TODO until lowering distinguishes section references from other base-array references?

https://github.com/llvm/llvm-project/pull/215997