diff --git a/irr/include/CIndexBuffer.h b/irr/include/CIndexBuffer.h
index 4318ddaab..904b0ab9a 100644
--- a/irr/include/CIndexBuffer.h
+++ b/irr/include/CIndexBuffer.h
@@ -7,6 +7,13 @@
 #include <vector>
 #include "IIndexBuffer.h"
 
+// Define to receive warnings when violating the hw mapping hints
+//#define INDEXBUFFER_HINT_DEBUG
+
+#ifdef INDEXBUFFER_HINT_DEBUG
+#include "../src/os.h"
+#endif
+
 namespace irr
 {
 namespace scene
@@ -58,6 +65,13 @@ public:
 	void setDirty() override
 	{
 		++ChangedID;
+#ifdef INDEXBUFFER_HINT_DEBUG
+		if (MappingHint == EHM_STATIC && HWBuffer) {
+			char buf[100];
+			snprintf_irr(buf, sizeof(buf), "CIndexBuffer @ %p modified, but it has a static hint", this);
+			os::Printer::log(buf, ELL_WARNING);
+		}
+#endif
 	}
 
 	u32 getChangedID() const override { return ChangedID; }
diff --git a/irr/include/CVertexBuffer.h b/irr/include/CVertexBuffer.h
index 3559bbddb..4b3f33688 100644
--- a/irr/include/CVertexBuffer.h
+++ b/irr/include/CVertexBuffer.h
@@ -7,6 +7,13 @@
 #include <vector>
 #include "IVertexBuffer.h"
 
+// Define to receive warnings when violating the hw mapping hints
+//#define VERTEXBUFFER_HINT_DEBUG
+
+#ifdef VERTEXBUFFER_HINT_DEBUG
+#include "../src/os.h"
+#endif
+
 namespace irr
 {
 namespace scene
@@ -87,6 +94,13 @@ public:
 	void setDirty() override
 	{
 		++ChangedID;
+#ifdef VERTEXBUFFER_HINT_DEBUG
+		if (MappingHint == EHM_STATIC && HWBuffer) {
+			char buf[100];
+			snprintf_irr(buf, sizeof(buf), "CVertexBuffer @ %p modified, but it has a static hint", this);
+			os::Printer::log(buf, ELL_WARNING);
+		}
+#endif
 	}
 
 	u32 getChangedID() const override { return ChangedID; }
diff --git a/irr/include/IReferenceCounted.h b/irr/include/IReferenceCounted.h
index e1000d389..68aa20fb6 100644
--- a/irr/include/IReferenceCounted.h
+++ b/irr/include/IReferenceCounted.h
@@ -42,7 +42,7 @@ class IReferenceCounted
 public:
 	//! Constructor.
 	IReferenceCounted() :
-			DebugName(0), ReferenceCounter(1)
+			ReferenceCounter(1)
 	{
 	}
 
@@ -136,6 +136,7 @@ public:
 		return ReferenceCounter;
 	}
 
+#ifdef _DEBUG
 	//! Returns the debug name of the object.
 	/** The Debugname may only be set and changed by the object
 	itself. This method should only be used in Debug mode.
@@ -157,7 +158,10 @@ protected:
 
 private:
 	//! The debug name.
-	const c8 *DebugName;
+	const c8 *DebugName = nullptr;
+#endif
+
+private:
 
 	//! The reference counter. Mutable to do reference counting on const objects.
 	mutable s32 ReferenceCounter;
diff --git a/irr/src/CMakeLists.txt b/irr/src/CMakeLists.txt
index 742d27f72..22a0d0093 100644
--- a/irr/src/CMakeLists.txt
+++ b/irr/src/CMakeLists.txt
@@ -510,6 +510,9 @@ target_link_libraries(IrrlichtMt PRIVATE
 if(WIN32)
 	target_compile_definitions(IrrlichtMt INTERFACE _IRR_WINDOWS_API_) # used in _IRR_DEBUG_BREAK_IF definition in a public header
 endif()
+if(CMAKE_BUILD_TYPE STREQUAL "Debug")
+	target_compile_definitions(IrrlichtMt INTERFACE _DEBUG) # same
+endif()
 if(APPLE OR ANDROID OR EMSCRIPTEN)
 	target_compile_definitions(IrrlichtMt PUBLIC IRR_MOBILE_PATHS)
 endif()
diff --git a/irr/src/os.h b/irr/src/os.h
index 58699ab3e..bcc096f95 100644
--- a/irr/src/os.h
+++ b/irr/src/os.h
@@ -52,7 +52,6 @@ public:
 	// prints out a string to the console out stdout or debug log or whatever
 	static void print(const c8 *message, ELOG_LEVEL ll = ELL_INFORMATION);
 	static void log(const c8 *message, ELOG_LEVEL ll = ELL_INFORMATION);
-	static void log(const wchar_t *message, ELOG_LEVEL ll = ELL_INFORMATION);
 
 	// The string ": " is added between message and hint
 	static void log(const c8 *message, const c8 *hint, ELOG_LEVEL ll = ELL_INFORMATION);