[libclang] If displayDiagnostics is set (when calling clang_createIndex), make sure to

output the errors that occurred even if we did not get an AST (e.g. because the
PCH failed to load).

Also honor displayDiagnostics in clang_indexSourceFile().

rdar://11203489

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@154472 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 39 insertions, 21 deletions

diff --git a/tools/libclang/CIndex.cpp b/tools/libclang/CIndex.cpp
index eafb867eb2..df4c8eda66 100644
--- a/tools/libclang/CIndex.cpp
+++ b/tools/libclang/CIndex.cpp
@@ -51,6 +51,7 @@ using namespace clang;
 using namespace clang::cxcursor;
 using namespace clang::cxstring;
 using namespace clang::cxtu;
+using namespace clang::cxindex;
 
 CXTranslationUnit cxtu::MakeCXTranslationUnit(CIndexer *CIdx, ASTUnit *TU) {
   if (!TU)
@@ -2482,7 +2483,28 @@ clang_createTranslationUnitFromSourceFile(CXIndex CIdx,
                                     unsaved_files, num_unsaved_files,
                                     Options);
 }
-  
+
+void cxindex::printDiagsToStderr(ASTUnit *Unit) {
+  if (!Unit)
+    return;
+
+  for (ASTUnit::stored_diag_iterator D = Unit->stored_diag_begin(), 
+                                  DEnd = Unit->stored_diag_end();
+       D != DEnd; ++D) {
+    CXStoredDiagnostic Diag(*D, Unit->getASTContext().getLangOpts());
+    CXString Msg = clang_formatDiagnostic(&Diag,
+                                clang_defaultDiagnosticDisplayOptions());
+    fprintf(stderr, "%s\n", clang_getCString(Msg));
+    clang_disposeString(Msg);
+  }
+#ifdef LLVM_ON_WIN32
+  // On Windows, force a flush, since there may be multiple copies of
+  // stderr and stdout in the file system, all with different buffers
+  // but writing to the same device.
+  fflush(stderr);
+#endif
+}
+
 struct ParseTranslationUnitInfo {
   CXIndex CIdx;
   const char *source_filename;
@@ -2587,6 +2609,7 @@ static void clang_parseTranslationUnit_Impl(void *UserData) {
   }
   
   unsigned NumErrors = Diags->getClient()->getNumErrors();
+  OwningPtr<ASTUnit> ErrUnit;
   OwningPtr<ASTUnit> Unit(
     ASTUnit::LoadFromCommandLine(Args->size() ? &(*Args)[0] : 0 
                                  /* vector::data() not portable */,
@@ -2601,27 +2624,13 @@ static void clang_parseTranslationUnit_Impl(void *UserData) {
                                  PrecompilePreamble,
                                  TUKind,
                                  CacheCodeCompetionResults,
-                                 /*AllowPCHWithCompilerErrors=*/true));
+                                 /*AllowPCHWithCompilerErrors=*/true,
+                                 &ErrUnit));
 
   if (NumErrors != Diags->getClient()->getNumErrors()) {
     // Make sure to check that 'Unit' is non-NULL.
-    if (CXXIdx->getDisplayDiagnostics() && Unit.get()) {
-      for (ASTUnit::stored_diag_iterator D = Unit->stored_diag_begin(), 
-                                      DEnd = Unit->stored_diag_end();
-           D != DEnd; ++D) {
-        CXStoredDiagnostic Diag(*D, Unit->getASTContext().getLangOpts());
-        CXString Msg = clang_formatDiagnostic(&Diag,
-                                    clang_defaultDiagnosticDisplayOptions());
-        fprintf(stderr, "%s\n", clang_getCString(Msg));
-        clang_disposeString(Msg);
-      }
-#ifdef LLVM_ON_WIN32
-      // On Windows, force a flush, since there may be multiple copies of
-      // stderr and stdout in the file system, all with different buffers
-      // but writing to the same device.
-      fflush(stderr);
-#endif
-    }
+    if (CXXIdx->getDisplayDiagnostics())
+      printDiagsToStderr(Unit ? Unit.get() : ErrUnit.get());
   }
 
   PTUI->result = MakeCXTranslationUnit(CXXIdx, Unit.take());
diff --git a/tools/libclang/CIndexer.h b/tools/libclang/CIndexer.h
index 8a249f0ceb..1e5fb824bb 100644
--- a/tools/libclang/CIndexer.h
+++ b/tools/libclang/CIndexer.h
@@ -25,6 +25,7 @@ namespace llvm {
 }
 
 namespace clang {
+  class ASTUnit;
 
 class CIndexer {
   bool OnlyLocalDecls;
@@ -94,6 +95,10 @@ public:
 
   /// \brief Print libclang's resource usage to standard error.
   void PrintLibclangResourceUsage(CXTranslationUnit TU);
+
+  namespace cxindex {
+    void printDiagsToStderr(ASTUnit *Unit);
+  }
 }
 
 #endif
diff --git a/tools/libclang/Indexing.cpp b/tools/libclang/Indexing.cpp
index 6ece54857a..e660c4d6eb 100644
--- a/tools/libclang/Indexing.cpp
+++ b/tools/libclang/Indexing.cpp
@@ -388,7 +388,8 @@ static void clang_indexSourceFile_Impl(void *UserData) {
     }
   }
 
-  Unit = ASTUnit::LoadFromCompilerInvocationAction(CInvok.getPtr(), Diags,
+  DiagnosticErrorTrap DiagTrap(*Diags);
+  bool Success = ASTUnit::LoadFromCompilerInvocationAction(CInvok.getPtr(), Diags,
                                                        IndexAction.get(),
                                                        Unit,
                                                        Persistent,
@@ -397,7 +398,10 @@ static void clang_indexSourceFile_Impl(void *UserData) {
                                                     /*CaptureDiagnostics=*/true,
                                                        PrecompilePreamble,
                                                     CacheCodeCompletionResults);
-  if (!Unit)
+  if (DiagTrap.hasErrorOccurred() && CXXIdx->getDisplayDiagnostics())
+    printDiagsToStderr(Unit);
+
+  if (!Success)
     return;
 
   if (out_TU)