diff --git a/src/lib.rs b/src/lib.rs
index c0f102670d..e9fb8ba7cb 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1464,6 +1464,11 @@ pub enum Statement {
         reject: Block,
     },
     /// Conditionally executes one of multiple blocks, based on the value of the selector.
+    ///
+    /// Some backends don't support fallthrough (HLSL due to FXC, WGSL).
+    /// However, a case clause with multiple selectors (and one body) gets translated as
+    /// a sequence of [`SwitchCase`]s with all but the last one having no body and marked
+    /// as fallthrough (which can get translated directly to all backends).
     Switch {
         selector: Handle<Expression>, //int
         cases: Vec<SwitchCase>,