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+An unsupported representation was attempted on a zero-variant enum.
+
+Erroneous code example:
+
+```compile_fail,E0084
+#[repr(i32)]
+enum NightsWatch {} // error: unsupported representation for zero-variant enum
+```
+
+It is impossible to define an integer type to be used to represent zero-variant
+enum values because there are no zero-variant enum values. There is no way to
+construct an instance of the following type using only safe code. So you have
+two solutions. Either you add variants in your enum:
+
+```
+#[repr(i32)]
+enum NightsWatch {
+    JonSnow,
+    Commander,
+}
+```
+
+or you remove the integer representation of your enum:
+
+```
+enum NightsWatch {}
+```