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// run-pass
#![allow(non_upper_case_globals)]
// Issue #13186
// For simplicity of explanations assuming code is compiled for x86_64
// Linux ABI.
// Size of TestOption<u64> is 16, and alignment of TestOption<u64> is 8.
// Size of u8 is 1, and alignment of u8 is 1.
// So size of Request is 24, and alignment of Request must be 8:
// the maximum alignment of its fields.
// Last 7 bytes of Request struct are not occupied by any fields.
enum TestOption<T> {
TestNone,
TestSome(T),
}
pub struct Request {
foo: TestOption<u64>,
bar: u8,
}
fn default_instance() -> &'static Request {
static instance: Request = Request {
// LLVM does not allow to specify alignment of expressions, thus
// alignment of `foo` in constant is 1, not 8.
foo: TestOption::TestNone,
bar: 17,
// Space after last field is not occupied by any data, but it is
// reserved to make struct aligned properly. If compiler does
// not insert padding after last field when emitting constant,
// size of struct may be not equal to size of struct, and
// compiler crashes in internal assertion check.
};
&instance
}
fn non_default_instance() -> &'static Request {
static instance: Request = Request {
foo: TestOption::TestSome(0x1020304050607080),
bar: 19,
};
&instance
}
pub fn main() {
match default_instance() {
&Request { foo: TestOption::TestNone, bar: 17 } => {},
_ => panic!(),
};
match non_default_instance() {
&Request { foo: TestOption::TestSome(0x1020304050607080), bar: 19 } => {},
_ => panic!(),
};
}
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