diff options
Diffstat (limited to 'src/test/ui/lint/opaque-ty-ffi-normalization-cycle.rs')
-rw-r--r-- | src/test/ui/lint/opaque-ty-ffi-normalization-cycle.rs | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/src/test/ui/lint/opaque-ty-ffi-normalization-cycle.rs b/src/test/ui/lint/opaque-ty-ffi-normalization-cycle.rs new file mode 100644 index 000000000..c83bca4a4 --- /dev/null +++ b/src/test/ui/lint/opaque-ty-ffi-normalization-cycle.rs @@ -0,0 +1,41 @@ +#![feature(type_alias_impl_trait)] +#![allow(unused)] +#![deny(improper_ctypes)] + +pub trait TraitA { + type Assoc; +} + +impl TraitA for u32 { + type Assoc = u32; +} + +pub trait TraitB { + type Assoc; +} + +impl<T> TraitB for T +where + T: TraitA, +{ + type Assoc = <T as TraitA>::Assoc; +} + +type AliasA = impl TraitA<Assoc = u32>; + +type AliasB = impl TraitB; + +fn use_of_a() -> AliasA { + 3 +} + +fn use_of_b() -> AliasB { + 3 +} + +extern "C" { + fn lint_me() -> <AliasB as TraitB>::Assoc; + //~^ ERROR `extern` block uses type `AliasB`, which is not FFI-safe +} + +fn main() {} |