[llvm] [clang] DiagnosticHandler: refactor error checking (PR #75889)

[Teresa Johnson via cfe-commits]

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@@ -256,10 +256,13 @@ void LLVMContext::diagnose(const DiagnosticInfo &DI) {
       RS->emit(*OptDiagBase);
 
   // If there is a report handler, use it.
-  if (pImpl->DiagHandler &&
-      (!pImpl->RespectDiagnosticFilters || isDiagnosticEnabled(DI)) &&
-      pImpl->DiagHandler->handleDiagnostics(DI))
-    return;
+  if (pImpl->DiagHandler) {
+    if (DI.getSeverity() == DS_Error)
+      pImpl->DiagHandler->HasErrors = true;
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teresajohnson wrote:

I didn't mean calling handle Diagnostics in more places. I just meant rather than directly setting the HasErrors flags here, do that in a new non-virtual method (e.g. prepareToHandleDiagnostics() or whatever), and call it here just before calling handle Diagnostics. To abstract away what it is actually doing and leave the setting of the flag to the DiagnosticHandler class.

https://github.com/llvm/llvm-project/pull/75889