diff --git a/core/metacling/src/TClingCallFunc.cxx b/core/metacling/src/TClingCallFunc.cxx
index 7d4b93c8810e0..d8938546e838a 100644
--- a/core/metacling/src/TClingCallFunc.cxx
+++ b/core/metacling/src/TClingCallFunc.cxx
@@ -72,8 +72,8 @@ C++ interpreter and the Clang C++ compiler, not CINT.
 #include <sstream>
 
 using namespace ROOT;
-using namespace llvm;
 using namespace clang;
+using llvm::APSInt, llvm::raw_string_ostream;
 using std::string, std::map, std::ostringstream, std::make_pair;
 
 static unsigned long long gWrapperSerial = 0LL;
diff --git a/interpreter/cling/lib/Interpreter/CIFactory.cpp b/interpreter/cling/lib/Interpreter/CIFactory.cpp
index 5ae94c42c103d..3d7fcf58231bf 100644
--- a/interpreter/cling/lib/Interpreter/CIFactory.cpp
+++ b/interpreter/cling/lib/Interpreter/CIFactory.cpp
@@ -1407,10 +1407,6 @@ namespace {
 #endif
 
     if (!COpts.HasOutput || !HasInput) {
-      // suppress the warning "argument unused during compilation: -c" of the
-      // device interpreter instance
-      if (!COpts.CUDADevice)
-        argvCompile.push_back("-c");
       argvCompile.push_back("-");
     }
 
diff --git a/interpreter/cling/lib/Interpreter/Value.cpp b/interpreter/cling/lib/Interpreter/Value.cpp
index 8529ecbcbbf9f..74f0557d65b78 100644
--- a/interpreter/cling/lib/Interpreter/Value.cpp
+++ b/interpreter/cling/lib/Interpreter/Value.cpp
@@ -272,7 +272,7 @@ namespace cling {
     const clang::BuiltinType *BT = getType()->castAs<clang::BuiltinType>();
     clang::PrintingPolicy Policy = getASTContext().getPrintingPolicy();
 #endif // NDEBUG
-    assert(BT->getName(Policy).equals(Type));
+    assert(BT->getName(Policy) == Type);
   }
 
   static clang::QualType getCorrespondingBuiltin(clang::ASTContext &C,
diff --git a/interpreter/cling/lib/Utils/AST.cpp b/interpreter/cling/lib/Utils/AST.cpp
index 3fd1e600b1061..e3533bdf5a1d1 100644
--- a/interpreter/cling/lib/Utils/AST.cpp
+++ b/interpreter/cling/lib/Utils/AST.cpp
@@ -357,6 +357,8 @@ namespace utils {
   static
   NestedNameSpecifier* GetFullyQualifiedNameSpecifier(const ASTContext& Ctx,
                                                   NestedNameSpecifier* scope) {
+    if (!scope)
+      return nullptr;
     // Return a fully qualified version of this name specifier
     if (scope->getKind() == NestedNameSpecifier::Global) {
       // Already fully qualified.