diff options
Diffstat (limited to 'tests/run-make-fulldeps/issue-97463-abi-param-passing/param_passing.rs')
-rw-r--r-- | tests/run-make-fulldeps/issue-97463-abi-param-passing/param_passing.rs | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/tests/run-make-fulldeps/issue-97463-abi-param-passing/param_passing.rs b/tests/run-make-fulldeps/issue-97463-abi-param-passing/param_passing.rs new file mode 100644 index 000000000..c11f3cc72 --- /dev/null +++ b/tests/run-make-fulldeps/issue-97463-abi-param-passing/param_passing.rs @@ -0,0 +1,38 @@ +// NOTE: Exposing the bug encoded in this test is sensitive to +// LLVM optimization choices. See additional note below for an +// example. + +#[link(name = "bad")] +extern "C" { + pub fn c_read_value(a: u32, b: u32, c: u32) -> u16; +} + +fn main() { + const C1: usize = 0x327b23c6; + const C2: usize = C1 & 0xFFFF; + + let r1: usize = 0x0; + let r2: usize = C1; + let r3: usize = 0x0; + let value: u16 = unsafe { c_read_value(r1 as u32, r2 as u32, r3 as u32) }; + + // NOTE: as an example of the sensitivity of this test to optimization choices, + // uncommenting this block of code makes the bug go away on pnkfelix's machine. + // (But observing via `dbg!` doesn't hide the bug. At least sometimes.) + /* + println!("{}", value); + println!("{}", value as usize); + println!("{}", usize::from(value)); + println!("{}", (value as usize) & 0xFFFF); + */ + + let d1 = value; + let d2 = value as usize; + let d3 = usize::from(value); + let d4 = (value as usize) & 0xFFFF; + + let d = (&d1, &d2, &d3, &d4); + let d_ = (d1, d2, d3, d4); + + assert_eq!(((&(C2 as u16), &C2, &C2, &C2), (C2 as u16, C2, C2, C2)), (d, d_)); +} |