Clang: Improve performance by reducing parsing

We generate one big file per project part so the preprocessor is skipping
the recurring includes.

This generated many errors about missing macros but we don't care
much about them during dependency collection step so we just
silence these errors with ignoring diagnostics consumer.

Change-Id: I5581d623b5d5f9995496252735577ea6b54790d9
Reviewed-by: Ivan Donchevskii <ivan.donchevskii@qt.io>

1 files changed, 17 insertions, 16 deletions

diff --git a/src/tools/clangpchmanagerbackend/source/collectbuilddependencyaction.h b/src/tools/clangpchmanagerbackend/source/collectbuilddependencyaction.h
index 03d27f9b21..fa1a10e79c 100644
--- a/src/tools/clangpchmanagerbackend/source/collectbuilddependencyaction.h
+++ b/src/tools/clangpchmanagerbackend/source/collectbuilddependencyaction.h
@@ -54,27 +54,28 @@ public:
 
     bool BeginSourceFileAction(clang::CompilerInstance &compilerInstance) override
     {
-      if (clang::PreprocessOnlyAction::BeginSourceFileAction(compilerInstance)) {
-          auto &preprocessor = compilerInstance.getPreprocessor();
+        if (clang::PreprocessOnlyAction::BeginSourceFileAction(compilerInstance)) {
+            auto &preprocessor = compilerInstance.getPreprocessor();
 
-          preprocessor.SetSuppressIncludeNotFoundError(true);
-          preprocessor.SetMacroExpansionOnlyInDirectives();
+            preprocessor.SetSuppressIncludeNotFoundError(true);
+            preprocessor.SetMacroExpansionOnlyInDirectives();
 
-          auto macroPreprocessorCallbacks = new CollectBuildDependencyPreprocessorCallbacks(
-                      m_buildDependency,
-                      m_filePathCache,
-                      m_excludedIncludeUID,
-                      m_alreadyIncludedFileUIDs,
-                      compilerInstance.getSourceManager(),
-                      m_sourcesManager,
-                      compilerInstance.getPreprocessorPtr());
+            auto macroPreprocessorCallbacks = new CollectBuildDependencyPreprocessorCallbacks(
+                m_buildDependency,
+                m_filePathCache,
+                m_excludedIncludeUID,
+                m_alreadyIncludedFileUIDs,
+                compilerInstance.getSourceManager(),
+                m_sourcesManager,
+                compilerInstance.getPreprocessorPtr());
 
-          preprocessor.addPPCallbacks(std::unique_ptr<clang::PPCallbacks>(macroPreprocessorCallbacks));
+            preprocessor.addPPCallbacks(
+                std::unique_ptr<clang::PPCallbacks>(macroPreprocessorCallbacks));
 
-          return true;
-      }
+            return true;
+        }
 
-      return false;
+        return false;
     }
 
     void EndSourceFileAction() override