diff --git a/src/video_core/primitive_assembly.h b/src/video_core/primitive_assembly.h
index c650646db..1f4f25af2 100644
--- a/src/video_core/primitive_assembly.h
+++ b/src/video_core/primitive_assembly.h
@@ -20,7 +20,7 @@ struct PrimitiveAssembler {
     using TriangleHandler =
         std::function<void(const VertexType& v0, const VertexType& v1, const VertexType& v2)>;
 
-    PrimitiveAssembler(
+    explicit PrimitiveAssembler(
         PipelineRegs::TriangleTopology topology = PipelineRegs::TriangleTopology::List);
 
     /*