[flang-commits] [flang] [flang][CUDA] Downgrade error to warning (PR #161570)

[Eugene Epshteyn via flang-commits]

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@@ -2387,44 +2403,51 @@ bool CheckArguments(const characteristics::Procedure &proc,
   evaluate::FoldingContext foldingContext{context.foldingContext()};
   parser::ContextualMessages &messages{foldingContext.messages()};
   bool allowArgumentConversions{true};
+  parser::Messages implicitBuffer;
   if (!explicitInterface || treatingExternalAsImplicit) {
-    parser::Messages buffer;
     {
-      auto restorer{messages.SetMessages(buffer)};
+      auto restorer{messages.SetMessages(implicitBuffer)};
       for (auto &actual : actuals) {
         if (actual) {
           CheckImplicitInterfaceArg(*actual, messages, context);
         }
       }
     }
-    if (!buffer.empty()) {
+    if (implicitBuffer.AnyFatalError()) {
       if (auto *msgs{messages.messages()}) {
-        msgs->Annex(std::move(buffer));
+        msgs->Annex(std::move(implicitBuffer));
       }
       return false; // don't pile on
     }
     allowArgumentConversions = false;
   }
   if (explicitInterface) {
-    auto buffer{CheckExplicitInterface(proc, actuals, context, &scope,
+    auto explicitBuffer{CheckExplicitInterface(proc, actuals, context, &scope,
         intrinsic, allowArgumentConversions,
         /*extentErrors=*/true, ignoreImplicitVsExplicit)};
-    if (!buffer.empty()) {
+    if (!explicitBuffer.empty()) {
       if (treatingExternalAsImplicit) {
-        if (auto *msg{foldingContext.Warn(
+        // Combine all messages into one warning
+        if (auto *warning{messages.Warn(/*inModuleFile=*/false,
+                context.languageFeatures(),
                 common::UsageWarning::KnownBadImplicitInterface,
                 "If the procedure's interface were explicit, this reference would be in error"_warn_en_US)}) {
-          buffer.AttachTo(*msg, parser::Severity::Because);
-        } else {
-          buffer.clear();
+          explicitBuffer.AttachTo(*warning, parser::Severity::Because);
         }
+      } else if (auto *msgs{messages.messages()}) {
+        msgs->Annex(std::move(explicitBuffer));
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eugeneepshteyn wrote:

Should there be check for `!explicitBuffer.empty()`, similar to `!implicitBuffer.empty()` check below?

https://github.com/llvm/llvm-project/pull/161570