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+#### Note: this error code is no longer emitted by the compiler.
+
+More than one function was declared with the `#[main]` attribute.
+
+Erroneous code example:
+
+```compile_fail
+#![feature(main)]
+
+#[main]
+fn foo() {}
+
+#[main]
+fn f() {} // error: multiple functions with a `#[main]` attribute
+```
+
+This error indicates that the compiler found multiple functions with the
+`#[main]` attribute. This is an error because there must be a unique entry
+point into a Rust program. Example:
+
+```compile_fail
+#![feature(main)]
+
+#[main]
+fn f() {} // ok!
+```