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+`#[cmse_nonsecure_entry]` functions require a C ABI
+
+Erroneous code example:
+
+```compile_fail,E0776
+#![feature(cmse_nonsecure_entry)]
+
+#[no_mangle]
+#[cmse_nonsecure_entry]
+pub fn entry_function(input: Vec<u32>) {}
+```
+
+To fix this error, declare your entry function with a C ABI, using `extern "C"`.