diff --git a/CMakeLists.txt b/CMakeLists.txt
index f00adc07..91b421ba 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -87,12 +87,7 @@ elseif(CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
         /we4554   # check operator precedence for possible error; use parentheses to clarify precedence
         /w14100   # unreferenced formal parameter
         /w14189   # local variable is initialized but not referenced
-        /we4456   # declaration of 'var' hides previous local declaration
-        )
-    if(CMAKE_CXX_FLAGS_RELWITHDEBINFO)
-        set(CMAKE_C_FLAGS_RELWITHDEBINFO "${CMAKE_C_FLAGS_RELWITHDEBINFO} /Ob2")
-        set(CMAKE_CXX_FLAGS_RELWITHDEBINFO "${CMAKE_CXX_FLAGS_RELWITHDEBINFO} /Ob2")
-    endif()
+        /we4456)  # declaration of 'var' hides previous local declaration
 endif()
 string(REPLACE ";" " " E2D_SHARED_CXX_FLAGS "${E2D_SHARED_CXX_FLAGS}")
 
diff --git a/samples/sources/sample_06/sample_06.cpp b/samples/sources/sample_06/sample_06.cpp
index 9947b56c..c8c64dfb 100644
--- a/samples/sources/sample_06/sample_06.cpp
+++ b/samples/sources/sample_06/sample_06.cpp
@@ -53,8 +53,8 @@ namespace
                 });
             }
 
-            owner.for_joined_components<spine_player_evt, spine_player>([
-            ](ecs::entity e, const spine_player_evt& pe, spine_player& p) {
+            owner.for_joined_components<spine_player_evt>([
+            ](ecs::entity e, const spine_player_evt& pe) {
                 for ( const auto& evt : pe.events() ) {
                     if ( auto complete_evt = std::get_if<spine_player_evt::complete_evt>(&evt);
                         complete_evt && complete_evt->message() == "to_walk" )
diff --git a/sources/3rdparty/bass/linux/bass.h b/sources/3rdparty/bass/linux/bass.h
index 388d4068..e3bf8dcc 100644
--- a/sources/3rdparty/bass/linux/bass.h
+++ b/sources/3rdparty/bass/linux/bass.h
@@ -724,7 +724,7 @@ typedef struct {
 	BYTE Reserved[190];
 #if defined(__GNUC__) && __GNUC__<3
 	char CodingHistory[0];			// history
-#elif 1 // change to 0 if compiler fails the following line
+#elif 0 // change to 0 if compiler fails the following line
 	char CodingHistory[];			// history
 #else
 	char CodingHistory[1];			// history
@@ -762,7 +762,7 @@ typedef struct
 	char URL[1024];					// uniform resource locator
 #if defined(__GNUC__) && __GNUC__<3
 	char TagText[0];				// free form text for scripts or tags
-#elif 1 // change to 0 if compiler fails the following line
+#elif 0 // change to 0 if compiler fails the following line
 	char TagText[];					// free form text for scripts or tags
 #else
 	char TagText[1];				// free form text for scripts or tags
@@ -785,7 +785,7 @@ typedef struct
 	DWORD dwCuePoints;
 #if defined(__GNUC__) && __GNUC__<3
 	TAG_CUE_POINT CuePoints[0];
-#elif 1 // change to 0 if compiler fails the following line
+#elif 0 // change to 0 if compiler fails the following line
 	TAG_CUE_POINT CuePoints[];
 #else
 	TAG_CUE_POINT CuePoints[1];
@@ -816,7 +816,7 @@ typedef struct
 	DWORD cbSamplerData;
 #if defined(__GNUC__) && __GNUC__<3
 	TAG_SMPL_LOOP SampleLoops[0];
-#elif 1 // change to 0 if compiler fails the following line
+#elif 0 // change to 0 if compiler fails the following line
 	TAG_SMPL_LOOP SampleLoops[];
 #else
 	TAG_SMPL_LOOP SampleLoops[1];
diff --git a/sources/3rdparty/bass/windows/bass.h b/sources/3rdparty/bass/windows/bass.h
index 388d4068..e3bf8dcc 100644
--- a/sources/3rdparty/bass/windows/bass.h
+++ b/sources/3rdparty/bass/windows/bass.h
@@ -724,7 +724,7 @@ typedef struct {
 	BYTE Reserved[190];
 #if defined(__GNUC__) && __GNUC__<3
 	char CodingHistory[0];			// history
-#elif 1 // change to 0 if compiler fails the following line
+#elif 0 // change to 0 if compiler fails the following line
 	char CodingHistory[];			// history
 #else
 	char CodingHistory[1];			// history
@@ -762,7 +762,7 @@ typedef struct
 	char URL[1024];					// uniform resource locator
 #if defined(__GNUC__) && __GNUC__<3
 	char TagText[0];				// free form text for scripts or tags
-#elif 1 // change to 0 if compiler fails the following line
+#elif 0 // change to 0 if compiler fails the following line
 	char TagText[];					// free form text for scripts or tags
 #else
 	char TagText[1];				// free form text for scripts or tags
@@ -785,7 +785,7 @@ typedef struct
 	DWORD dwCuePoints;
 #if defined(__GNUC__) && __GNUC__<3
 	TAG_CUE_POINT CuePoints[0];
-#elif 1 // change to 0 if compiler fails the following line
+#elif 0 // change to 0 if compiler fails the following line
 	TAG_CUE_POINT CuePoints[];
 #else
 	TAG_CUE_POINT CuePoints[1];
@@ -816,7 +816,7 @@ typedef struct
 	DWORD cbSamplerData;
 #if defined(__GNUC__) && __GNUC__<3
 	TAG_SMPL_LOOP SampleLoops[0];
-#elif 1 // change to 0 if compiler fails the following line
+#elif 0 // change to 0 if compiler fails the following line
 	TAG_SMPL_LOOP SampleLoops[];
 #else
 	TAG_SMPL_LOOP SampleLoops[1];
diff --git a/sources/enduro2d/core/render_impl/render_opengl.cpp b/sources/enduro2d/core/render_impl/render_opengl.cpp
index aeab0126..8cb6410f 100644
--- a/sources/enduro2d/core/render_impl/render_opengl.cpp
+++ b/sources/enduro2d/core/render_impl/render_opengl.cpp
@@ -1100,6 +1100,7 @@ namespace e2d
 
         if ( tex->decl().is_compressed() ) {
             const v2u block_size = tex->decl().block_size();
+            E2D_UNUSED(block_size);
             E2D_ASSERT(region.position.x % block_size.x == 0 && region.position.y % block_size.y == 0);
             E2D_ASSERT(region.size.x % block_size.x == 0 && region.size.y % block_size.y == 0);
             opengl::with_gl_bind_texture(state_->dbg(), tex->state().id(),
diff --git a/untests/sources/untests_utils/intrusive_ptr.cpp b/untests/sources/untests_utils/intrusive_ptr.cpp
index d460d6e1..03cc6551 100644
--- a/untests/sources/untests_utils/intrusive_ptr.cpp
+++ b/untests/sources/untests_utils/intrusive_ptr.cpp
@@ -231,7 +231,7 @@ TEST_CASE("intrusive_ptr") {
         REQUIRE(obj_t::dtor_counter == 4u);
     }
     {
-        std::make_unique<obj_t>(10);
+        E2D_UNUSED(std::make_unique<obj_t>(10));
         intrusive_ptr<const obj_t> p1(new derived2_t());
         intrusive_ptr<const derived2_t> p2 = static_pointer_cast<const derived2_t>(p1);
         REQUIRE(p2->i == 21);