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// stderr-per-bitwidth
use std::mem::transmute;
fn get_flag<const FlagSet: bool, const ShortName: char>() -> Option<char> {
if FlagSet {
Some(ShortName)
} else {
None
}
}
union CharRaw {
byte: u8,
character: char,
}
union BoolRaw {
byte: u8,
boolean: bool,
}
const char_raw: CharRaw = CharRaw { byte: 0xFF };
const bool_raw: BoolRaw = BoolRaw { byte: 0x42 };
fn main() {
// Test that basic cases don't work
assert!(get_flag::<true, 'c'>().is_some());
assert!(get_flag::<false, 'x'>().is_none());
get_flag::<false, 0xFF>();
//~^ ERROR mismatched types
get_flag::<7, 'c'>();
//~^ ERROR mismatched types
get_flag::<42, 0x5ad>();
//~^ ERROR mismatched types
//~| ERROR mismatched types
get_flag::<false, { unsafe { char_raw.character } }>();
//~^ ERROR evaluation of constant value failed
//~| uninitialized
get_flag::<{ unsafe { bool_raw.boolean } }, 'z'>();
//~^ ERROR it is undefined behavior
get_flag::<{ unsafe { bool_raw.boolean } }, { unsafe { char_raw.character } }>();
//~^ ERROR evaluation of constant value failed
//~| uninitialized
//~| ERROR it is undefined behavior
}
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