Try some things to figure out why overload resolution is broken.

test/constant_buffer.shd

@@ -1,12 +1,12 @@
-Camera_Data :: constant_buffer {
+camera :: constant_buffer {
 	projection : float4x4;
 	view       : float4x4;
 }
 
 vertex main :: (pos : float4 @position) -> float4 @position {
-	return mul(projection, mul(view, pos));
+	return mul(camera.projection, mul(camera.view, pos));
 }
 
 pixel main :: () -> float4 @target {
-	return float(0.5, 0.5, 0.5, 1.0);
+	return float4(0.5, 0.5, 0.5, 1.0);
 }