[flang] [llvm] [flang] [flang-rt] Implement AT edit descriptor for Fortran 202X with appropriate handling and tests (PR #189157)

[via llvm-commits]

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@@ -718,6 +722,19 @@ template <typename CHAR> bool FormatValidator<CHAR>::Check() {
       NextToken();
       check_w();
       break;
+    case TokenKind::AT:
+      // F202X data-edit-desc -> AT (no w allowed)
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kwyatt-ext wrote:

F2023

https://github.com/llvm/llvm-project/pull/189157