In the case of an inout signature element, we do not pass through components not modified by the shader unless no components are touched.
The following test case succeeds if you do not write to pos.w, but fails with a validation error if you do since we do not output pos.xyz. Fxc does pass these through, so we should fix this.
In the case of an inout signature element, we do not pass through components not modified by the shader unless no components are touched.
The following test case succeeds if you do not write to pos.w, but fails with a validation error if you do since we do not output pos.xyz. Fxc does pass these through, so we should fix this.