Fix Conditioanl<T, false> fields with a semantic. (#7855)

* Fix Conditioanl<T, false> fields with a semantic.

* Add unit test.

* Fix test.

1 files changed, 23 insertions, 0 deletions

diff --git a/tests/language-feature/types/conditional-varying.slang b/tests/language-feature/types/conditional-varying.slang
new file mode 100644
index 000000000..674ae96e7
--- /dev/null
+++ b/tests/language-feature/types/conditional-varying.slang
@@ -0,0 +1,23 @@
+//TEST:SIMPLE(filecheck=CHECK): -target spirv
+//TEST:SIMPLE(filecheck=HLSL): -target hlsl -entry fragMain -profile ps_6_0
+
+// CHECK: OpEntryPoint
+// HLSL: float4 fragMain() : SV_TARGET
+
+extern static const bool enableConditional = false;
+
+struct Vertex
+{
+    Conditional<float3, enableConditional> color : COLOR;
+}
+
+[shader("fragment")]
+float4 fragMain(Vertex v) : SV_Target
+{
+    if (let c = v.color.get())
+    {
+        // This block should not be executed.
+        return float4(c, 1.0f);
+    }
+    return float4(0.0f, 0.0f, 0.0f, 1.0f);
+}
\ No newline at end of file