[flang-commits] [flang] [flang][openacc] Make OpenACC block construct parse errors less verbose. (PR #131042)

[Peter Klausler via flang-commits]

================
@@ -272,19 +272,51 @@ static llvm::raw_ostream::Colors PrefixColor(Severity severity) {
   return llvm::raw_ostream::SAVEDCOLOR;
 }
 
+// TODO: Make these configurable, based on verbosity level.
+const int MAX_CONTEXTS_EMITTED = 2;
+const bool OMIT_SHARED_CONTEXTS = true;
+
 void Message::Emit(llvm::raw_ostream &o, const AllCookedSources &allCooked,
     bool echoSourceLine) const {
   std::optional<ProvenanceRange> provenanceRange{GetProvenanceRange(allCooked)};
   const AllSources &sources{allCooked.allSources()};
   sources.EmitMessage(o, provenanceRange, ToString(), Prefix(severity()),
       PrefixColor(severity()), echoSourceLine);
+  // Always refers to if the attachment in the loop below is a context.
   bool isContext{attachmentIsContext_};
+  int contextsEmitted{0};
+  // Emit attachments.
   for (const Message *attachment{attachment_.get()}; attachment;
-       attachment = attachment->attachment_.get()) {
+      isContext = attachment->attachmentIsContext_,
+      attachment = attachment->attachment_.get()) {
     Severity severity = isContext ? Severity::Context : attachment->severity();
-    sources.EmitMessage(o, attachment->GetProvenanceRange(allCooked),
-        attachment->ToString(), Prefix(severity), PrefixColor(severity),
-        echoSourceLine);
+    auto emitAttachment = [&]() {
+      sources.EmitMessage(o, attachment->GetProvenanceRange(allCooked),
+          attachment->ToString(), Prefix(severity), PrefixColor(severity),
+          echoSourceLine);
+    };
+
+    if (isContext) {
+      // Truncate the number of contexts emitted.
+      if (contextsEmitted < MAX_CONTEXTS_EMITTED) {
+        emitAttachment();
+        contextsEmitted += 1;
+      }
+      if (OMIT_SHARED_CONTEXTS) {
----------------
klausler wrote:

`if constexpr`

https://github.com/llvm/llvm-project/pull/131042