From c04c4cb6e4b02b44501ab8e136616cbccaabd602 Mon Sep 17 00:00:00 2001 From: Ryan1729 Date: Thu, 6 Aug 2020 20:28:29 -0600 Subject: [PATCH] copy over *.fixed file --- .../transmutes_expressible_as_ptr_casts.fixed | 77 +++++++++++++++++++ 1 file changed, 77 insertions(+) create mode 100644 src/tools/clippy/tests/ui/transmutes_expressible_as_ptr_casts.fixed diff --git a/src/tools/clippy/tests/ui/transmutes_expressible_as_ptr_casts.fixed b/src/tools/clippy/tests/ui/transmutes_expressible_as_ptr_casts.fixed new file mode 100644 index 00000000000..ab181687e1e --- /dev/null +++ b/src/tools/clippy/tests/ui/transmutes_expressible_as_ptr_casts.fixed @@ -0,0 +1,77 @@ +// run-rustfix +#![warn(clippy::transmutes_expressible_as_ptr_casts)] +// These two warnings currrently cover the cases transmutes_expressible_as_ptr_casts +// would otherwise be responsible for +#![warn(clippy::useless_transmute)] +#![warn(clippy::transmute_ptr_to_ptr)] + +use std::mem::transmute; + +// rustc_typeck::check::cast contains documentation about when a cast `e as U` is +// valid, which we quote from below. + +fn main() { + // We should see an error message for each transmute, and no error messages for + // the casts, since the casts are the recommended fixes. + + // e is an integer and U is *U_0, while U_0: Sized; addr-ptr-cast + let ptr_i32_transmute = unsafe { + -1 as *const i32 + }; + let ptr_i32 = -1isize as *const i32; + + // e has type *T, U is *U_0, and either U_0: Sized ... + let ptr_i8_transmute = unsafe { + ptr_i32 as *const i8 + }; + let ptr_i8 = ptr_i32 as *const i8; + + let slice_ptr = &[0,1,2,3] as *const [i32]; + + // ... or pointer_kind(T) = pointer_kind(U_0); ptr-ptr-cast + let ptr_to_unsized_transmute = unsafe { + slice_ptr as *const [u16] + }; + let ptr_to_unsized = slice_ptr as *const [u16]; + // TODO: We could try testing vtable casts here too, but maybe + // we should wait until std::raw::TraitObject is stabilized? + + // e has type *T and U is a numeric type, while T: Sized; ptr-addr-cast + let usize_from_int_ptr_transmute = unsafe { + ptr_i32 as usize + }; + let usize_from_int_ptr = ptr_i32 as usize; + + let array_ref: &[i32; 4] = &[1,2,3,4]; + + // e has type &[T; n] and U is *const T; array-ptr-cast + let array_ptr_transmute = unsafe { + array_ref as *const [i32; 4] + }; + let array_ptr = array_ref as *const [i32; 4]; + + fn foo(_: usize) -> u8 { 42 } + + // e is a function pointer type and U has type *T, while T: Sized; fptr-ptr-cast + let usize_ptr_transmute = unsafe { + foo as *const usize + }; + let usize_ptr_transmute = foo as *const usize; + + // e is a function pointer type and U is an integer; fptr-addr-cast + let usize_from_fn_ptr_transmute = unsafe { + foo as usize + }; + let usize_from_fn_ptr = foo as *const usize; +} + +// If a ref-to-ptr cast of this form where the pointer type points to a type other +// than the referenced type, calling `CastCheck::do_check` has been observed to +// cause an ICE error message. `do_check` is currently called inside the +// `transmutes_expressible_as_ptr_casts` check, but other, more specific lints +// currently prevent it from being called in these cases. This test is meant to +// fail if the ordering of the checks ever changes enough to cause these cases to +// fall through into `do_check`. +fn trigger_do_check_to_emit_error(in_param: &[i32; 1]) -> *const u8 { + unsafe { in_param as *const [i32; 1] as *const u8 } +}