diff --git a/core/src/iter/traits/accum.rs b/core/src/iter/traits/accum.rs index c97cd042ab459..5b7d95c2f65e6 100644 --- a/core/src/iter/traits/accum.rs +++ b/core/src/iter/traits/accum.rs @@ -104,7 +104,7 @@ macro_rules! float_sum_product { impl Sum for $a { fn sum>(iter: I) -> Self { iter.fold( - 0.0, + -0.0, #[rustc_inherit_overflow_checks] |a, b| a + b, ) @@ -126,7 +126,7 @@ macro_rules! float_sum_product { impl<'a> Sum<&'a $a> for $a { fn sum>(iter: I) -> Self { iter.fold( - 0.0, + -0.0, #[rustc_inherit_overflow_checks] |a, b| a + b, ) diff --git a/core/tests/num/float_iter_sum_identity.rs b/core/tests/num/float_iter_sum_identity.rs new file mode 100644 index 0000000000000..6d3224522a830 --- /dev/null +++ b/core/tests/num/float_iter_sum_identity.rs @@ -0,0 +1,27 @@ +#[test] +fn f32_ref() { + let x: f32 = -0.0; + let still_x: f32 = [x].iter().sum(); + assert_eq!(1. / x, 1. / still_x) +} + +#[test] +fn f32_own() { + let x: f32 = -0.0; + let still_x: f32 = [x].into_iter().sum(); + assert_eq!(1. / x, 1. / still_x) +} + +#[test] +fn f64_ref() { + let x: f64 = -0.0; + let still_x: f64 = [x].iter().sum(); + assert_eq!(1. / x, 1. / still_x) +} + +#[test] +fn f64_own() { + let x: f64 = -0.0; + let still_x: f64 = [x].into_iter().sum(); + assert_eq!(1. / x, 1. / still_x) +} diff --git a/core/tests/num/mod.rs b/core/tests/num/mod.rs index 9d2912c4b22dc..53ff5ab1cedd1 100644 --- a/core/tests/num/mod.rs +++ b/core/tests/num/mod.rs @@ -30,6 +30,7 @@ mod int_log; mod ops; mod wrapping; +mod float_iter_sum_identity; mod ieee754; mod nan;