diff --git a/source/blender/functions/FN_cpp_type.hh b/source/blender/functions/FN_cpp_type.hh
index d580ce54f1d..236baf303e0 100644
--- a/source/blender/functions/FN_cpp_type.hh
+++ b/source/blender/functions/FN_cpp_type.hh
@@ -70,6 +70,7 @@
 #include "BLI_math_base.h"
 #include "BLI_string_ref.hh"
 
+namespace blender {
 namespace FN {
 
 using blender::IndexMask;
@@ -719,13 +720,14 @@ static std::unique_ptr<const CPPType> create_cpp_type(StringRef name, const T &d
 }
 
 }  // namespace FN
+}  // namespace blender
 
 #define MAKE_CPP_TYPE(IDENTIFIER, TYPE_NAME) \
   static TYPE_NAME default_value_##IDENTIFIER; \
-  static std::unique_ptr<const FN::CPPType> CPPTYPE_##IDENTIFIER##_owner = \
-      FN::create_cpp_type<TYPE_NAME>(STRINGIFY(IDENTIFIER), default_value_##IDENTIFIER); \
-  const FN::CPPType &CPPType_##IDENTIFIER = *CPPTYPE_##IDENTIFIER##_owner; \
-  template<> const FN::CPPType &FN::CPPType::get<TYPE_NAME>() \
+  static std::unique_ptr<const blender::FN::CPPType> CPPTYPE_##IDENTIFIER##_owner = \
+      blender::FN::create_cpp_type<TYPE_NAME>(STRINGIFY(IDENTIFIER), default_value_##IDENTIFIER); \
+  const blender::FN::CPPType &CPPType_##IDENTIFIER = *CPPTYPE_##IDENTIFIER##_owner; \
+  template<> const blender::FN::CPPType &blender::FN::CPPType::get<TYPE_NAME>() \
   { \
     return CPPType_##IDENTIFIER; \
   }
diff --git a/source/blender/functions/FN_cpp_types.hh b/source/blender/functions/FN_cpp_types.hh
index eceb43beb9d..6ee8788cd52 100644
--- a/source/blender/functions/FN_cpp_types.hh
+++ b/source/blender/functions/FN_cpp_types.hh
@@ -26,6 +26,7 @@
 
 #include "FN_cpp_type.hh"
 
+namespace blender {
 namespace FN {
 
 extern const CPPType &CPPType_bool;
@@ -44,5 +45,6 @@ extern const CPPType &CPPType_Color4b;
 extern const CPPType &CPPType_string;
 
 }  // namespace FN
+}  // namespace blender
 
 #endif /* __FN_CPP_TYPES_HH__ */
diff --git a/source/blender/functions/intern/cpp_types.cc b/source/blender/functions/intern/cpp_types.cc
index 6e548d65192..6339250caa5 100644
--- a/source/blender/functions/intern/cpp_types.cc
+++ b/source/blender/functions/intern/cpp_types.cc
@@ -21,6 +21,7 @@
 #include "BLI_float3.hh"
 #include "BLI_float4x4.hh"
 
+namespace blender {
 namespace FN {
 
 MAKE_CPP_TYPE(bool, bool)
@@ -39,3 +40,4 @@ MAKE_CPP_TYPE(Color4b, blender::Color4b)
 MAKE_CPP_TYPE(string, std::string)
 
 }  // namespace FN
+}  // namespace blender
diff --git a/tests/gtests/functions/FN_cpp_type_test.cc b/tests/gtests/functions/FN_cpp_type_test.cc
index ca8583bdc92..811e1a5d783 100644
--- a/tests/gtests/functions/FN_cpp_type_test.cc
+++ b/tests/gtests/functions/FN_cpp_type_test.cc
@@ -19,6 +19,9 @@
 
 #include "FN_cpp_type.hh"
 
+namespace blender {
+namespace FN {
+
 static const int default_constructed_value = 1;
 static const int copy_constructed_value = 2;
 static const int move_constructed_value = 3;
@@ -297,3 +300,6 @@ TEST(cpp_type, FillUninitialized)
   EXPECT_EQ(buffer2[8], copy_constructed_value);
   EXPECT_EQ(buffer2[9], 0);
 }
+
+}  // namespace FN
+}  // namespace blender