fix: Ignore includeNotFoundErrors in order to keep visiting the entire AST

With llvm 7.0.1 metadata generation may be interrupted by includeNotFound error. Since in 4.0.1 'includeNotFound' errors are ignored for some reason (even though the 'suppressIncludeNotFound' setting is false) here we set this explicitly in order to keep the same behavior

Author: tdermendjiev

src/main.cpp

@@ -131,6 +131,11 @@ class MetaGenerationFrontendAction : public clang::ASTFrontendAction {
 
     virtual std::unique_ptr<clang::ASTConsumer> CreateASTConsumer(clang::CompilerInstance& Compiler, llvm::StringRef InFile) override
     {
+        // Since in 4.0.1 'includeNotFound' errors are ignored for some reason
+        // (even though the 'suppressIncludeNotFound' setting is false)
+        // here we set this explicitly in order to keep the same behavior
+        Compiler.getPreprocessor().SetSuppressIncludeNotFoundError(true);
+        
         return std::unique_ptr<clang::ASTConsumer>(new MetaGenerationConsumer(Compiler.getASTContext().getSourceManager(), Compiler.getPreprocessor().getHeaderSearchInfo()));
     }
 };