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+Conflicting representation hints have been used on a same item.
+
+Erroneous code example:
+
+```compile_fail,E0566
+#[repr(u32, u64)]
+enum Repr { A }
+```
+
+In most cases (if not all), using just one representation hint is more than
+enough. If you want to have a representation hint depending on the current
+architecture, use `cfg_attr`. Example:
+
+```
+#[cfg_attr(linux, repr(u32))]
+#[cfg_attr(not(linux), repr(u64))]
+enum Repr { A }
+```