When building a module, forward diagnostics to the outer diagnostic consumer.

Previously, we would clone the current diagnostic consumer to produce
a new diagnostic consumer to use when building a module. The problem
here is that we end up losing diagnostics for important diagnostic
consumers, such as serialized diagnostics (where we'd end up with two
diagnostic consumers writing the same output file). With forwarding,
the diagnostics from all of the different modules being built get
forwarded to the one serialized-diagnostic consumer and are emitted in
a sane way.

Fixes <rdar://problem/13663996>.

llvm-svn: 181067

1 files changed, 24 insertions, 4 deletions

diff --git a/clang/lib/Frontend/ASTUnit.cpp b/clang/lib/Frontend/ASTUnit.cpp
index c1115aedbf8..1b4e5a0b39a 100644
--- a/clang/lib/Frontend/ASTUnit.cpp
+++ b/clang/lib/Frontend/ASTUnit.cpp
@@ -236,6 +236,11 @@ ASTUnit::ASTUnit(bool _MainFileIsAST)
 }
 
 ASTUnit::~ASTUnit() {
+  // If we loaded from an AST file, balance out the BeginSourceFile call.
+  if (MainFileIsAST && getDiagnostics().getClient()) {
+    getDiagnostics().getClient()->EndSourceFile();
+  }
+
   clearFileLevelDecls();
 
   // Clean up the temporary files and the preamble file.
@@ -581,14 +586,22 @@ private:
   }
 };
 
+  /// \brief Diagnostic consumer that saves each diagnostic it is given.
 class StoredDiagnosticConsumer : public DiagnosticConsumer {
   SmallVectorImpl<StoredDiagnostic> &StoredDiags;
-  
+  SourceManager *SourceMgr;
+
 public:
   explicit StoredDiagnosticConsumer(
                           SmallVectorImpl<StoredDiagnostic> &StoredDiags)
-    : StoredDiags(StoredDiags) { }
-  
+    : StoredDiags(StoredDiags), SourceMgr(0) { }
+
+  virtual void BeginSourceFile(const LangOptions &LangOpts,
+                               const Preprocessor *PP = 0) {
+    if (PP)
+      SourceMgr = &PP->getSourceManager();
+  }
+
   virtual void HandleDiagnostic(DiagnosticsEngine::Level Level,
                                 const Diagnostic &Info);
   
@@ -635,7 +648,11 @@ void StoredDiagnosticConsumer::HandleDiagnostic(DiagnosticsEngine::Level Level,
   // Default implementation (Warnings/errors count).
   DiagnosticConsumer::HandleDiagnostic(Level, Info);
 
-  StoredDiags.push_back(StoredDiagnostic(Level, Info));
+  // Only record the diagnostic if it's part of the source manager we know
+  // about. This effectively drops diagnostics from modules we're building.
+  // FIXME: In the long run, ee don't want to drop source managers from modules.
+  if (!Info.hasSourceManager() || &Info.getSourceManager() == SourceMgr)
+    StoredDiags.push_back(StoredDiagnostic(Level, Info));
 }
 
 ASTDeserializationListener *ASTUnit::getDeserializationListener() {
@@ -835,6 +852,9 @@ ASTUnit *ASTUnit::LoadFromASTFile(const std::string &Filename,
   ReaderPtr->InitializeSema(*AST->TheSema);
   AST->Reader = ReaderPtr;
 
+  // Tell the diagnostic client that we have started a source file.
+  AST->getDiagnostics().getClient()->BeginSourceFile(Context.getLangOpts(),&PP);
+
   return AST.take();
 }