[flang-commits] [flang] [flang] Diagnose assumed-type statement function dummy arguments (PR #227694)

[Yusuke MINATO via flang-commits]

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@@ -1704,6 +1701,28 @@ void CheckHelper::CheckSubprogram(
             *host);
       }
     }
+    // F2023 15.6.4: the length of a CHARACTER statement function result or
+    // dummy argument shall be a constant specification expression.
+    auto checkCharLength{[&](const Symbol &entity, const char *what) {
+      if (const DeclTypeSpec * type{entity.GetType()};
+          type && type->category() == DeclTypeSpec::Character) {
+        const ParamValue &length{type->characterTypeSpec().length()};
+        if (length.isExplicit() && length.GetExplicit() &&
+            !evaluate::IsConstantExpr(*length.GetExplicit())) {
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yus3710-fj wrote:

I'm not familiar with the implementation of semantics, but is there already something similar? If not, I think it might be better to extract this into a separate function so we can easily reuse it.

https://github.com/llvm/llvm-project/pull/227694