diff --git a/src/gl/scene/gl_sprite.cpp b/src/gl/scene/gl_sprite.cpp
index acd1d6d5d..f3b698360 100644
--- a/src/gl/scene/gl_sprite.cpp
+++ b/src/gl/scene/gl_sprite.cpp
@@ -682,7 +682,7 @@ void GLSprite::Process(AActor* thing, sector_t * sector, int thruportal)
 
 	// check renderrequired vs ~r_rendercaps, if anything matches we don't support that feature,
 	// check renderhidden vs r_rendercaps, if anything matches we do support that feature and should hide it.
-	if (!r_debug_disable_vis_filter && (!!(thing->RenderRequired & ~r_renderercaps)) ||
+	if ((!r_debug_disable_vis_filter && !!(thing->RenderRequired & ~r_renderercaps)) ||
 		(!!(thing->RenderHidden & r_renderercaps)))
 		return;
 
@@ -1298,4 +1298,4 @@ void GLSceneDrawer::RenderActorsInPortal(FGLLinePortal *glport)
 			}
 		}
 	}
-}
\ No newline at end of file
+}
diff --git a/src/polyrenderer/scene/poly_sprite.cpp b/src/polyrenderer/scene/poly_sprite.cpp
index 185f009a9..02667b19b 100644
--- a/src/polyrenderer/scene/poly_sprite.cpp
+++ b/src/polyrenderer/scene/poly_sprite.cpp
@@ -294,7 +294,7 @@ bool RenderPolySprite::IsThingCulled(AActor *thing)
 
 	// check renderrequired vs ~r_rendercaps, if anything matches we don't support that feature,
 	// check renderhidden vs r_rendercaps, if anything matches we do support that feature and should hide it.
-	if (!r_debug_disable_vis_filter && (!!(thing->RenderRequired & ~r_renderercaps)) ||
+	if ((!r_debug_disable_vis_filter && !!(thing->RenderRequired & ~r_renderercaps)) ||
 		(!!(thing->RenderHidden & r_renderercaps)))
 		return true;
 
diff --git a/src/sound/mididevices/music_timiditypp_mididevice.cpp b/src/sound/mididevices/music_timiditypp_mididevice.cpp
index 254b840a0..934ceacbb 100644
--- a/src/sound/mididevices/music_timiditypp_mididevice.cpp
+++ b/src/sound/mididevices/music_timiditypp_mididevice.cpp
@@ -545,7 +545,7 @@ bool TimidityPPMIDIDevice::LaunchTimidity ()
 	globfree(&glb);
 
 	int strCount = 1;
-	for (spaceIdx = 0; spaceIdx < CommandLine.Len(); spaceIdx++)
+	for (spaceIdx = 0; spaceIdx < static_cast<int>(CommandLine.Len()); spaceIdx++)
 	{
 		if (CommandLine[spaceIdx] == ' ')
 		{
diff --git a/src/swrenderer/scene/r_opaque_pass.cpp b/src/swrenderer/scene/r_opaque_pass.cpp
index 5935b1ff4..03467ce72 100644
--- a/src/swrenderer/scene/r_opaque_pass.cpp
+++ b/src/swrenderer/scene/r_opaque_pass.cpp
@@ -972,7 +972,7 @@ namespace swrenderer
 
 		// check renderrequired vs ~r_rendercaps, if anything matches we don't support that feature,
 		// check renderhidden vs r_rendercaps, if anything matches we do support that feature and should hide it.
-		if (!r_debug_disable_vis_filter && (!!(thing->RenderRequired & ~r_renderercaps)) ||
+		if ((!r_debug_disable_vis_filter && !!(thing->RenderRequired & ~r_renderercaps)) ||
 			(!!(thing->RenderHidden & r_renderercaps)))
 			return false;