Fix sync fallout

clippy_lints/src/transmute.rs

@@ -61,12 +61,14 @@ declare_clippy_lint! {
     ///
     /// **Example:**
     ///
-    /// ```rust,ignore
+    /// ```rust
-    /// core::intrinsics::transmute::<*const [i32], *const [u16]>(p)
+    /// # let p: *const [i32] = &[];
+    /// unsafe { std::mem::transmute::<*const [i32], *const [u16]>(p) };
     /// ```
     /// Use instead:
     /// ```rust
-    /// p as *const [u16]
+    /// # let p: *const [i32] = &[];
+    /// p as *const [u16];
     /// ```
     pub TRANSMUTES_EXPRESSIBLE_AS_PTR_CASTS,
     complexity,
@@ -704,14 +706,14 @@ fn can_be_expressed_as_pointer_cast<'tcx>(
     from_ty: Ty<'tcx>,
     to_ty: Ty<'tcx>,
 ) -> bool {
-    use CastKind::*;
+    use CastKind::{AddrPtrCast, ArrayPtrCast, FnPtrAddrCast, FnPtrPtrCast, PtrAddrCast, PtrPtrCast};
     matches!(
         check_cast(cx, e, from_ty, to_ty),
         Some(PtrPtrCast | PtrAddrCast | AddrPtrCast | ArrayPtrCast | FnPtrPtrCast | FnPtrAddrCast)
     )
 }
 
-/// If a cast from from_ty to to_ty is valid, returns an Ok containing the kind of
+/// If a cast from `from_ty` to `to_ty` is valid, returns an Ok containing the kind of
 /// the cast. In certain cases, including some invalid casts from array references
 /// to pointers, this may cause additional errors to be emitted and/or ICE error
 /// messages. This function will panic if that occurs.

tests/compile-test.rs

@@ -147,9 +147,6 @@ fn run_ui_toml(config: &mut compiletest::Config) {
 }
 
 fn run_ui_cargo(config: &mut compiletest::Config) {
-    if cargo::is_rustc_test_suite() {
-        return;
-    }
     fn run_tests(
         config: &compiletest::Config,
         filter: &Option<String>,
@@ -217,6 +214,10 @@ fn run_ui_cargo(config: &mut compiletest::Config) {
         Ok(result)
     }
 
+    if cargo::is_rustc_test_suite() {
+        return;
+    }
+
     config.mode = TestMode::Ui;
     config.src_base = Path::new("tests").join("ui-cargo").canonicalize().unwrap();
 

tests/ui/transmutes_expressible_as_ptr_casts.fixed

@@ -9,60 +9,48 @@
 
 use std::mem::{size_of, transmute};
 
-// rustc_typeck::check::cast contains documentation about when a cast `e as U` is 
+// 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 {
+    let _ptr_i32_transmute = unsafe { usize::MAX as *const i32 };
-        usize::MAX as *const i32
-    };
     let ptr_i32 = usize::MAX as *const i32;
 
     // e has type *T, U is *U_0, and either U_0: Sized ...
-    let _ptr_i8_transmute = unsafe {
+    let _ptr_i8_transmute = unsafe { ptr_i32 as *const i8 };
-        ptr_i32 as *const i8
-    };
     let _ptr_i8 = ptr_i32 as *const i8;
 
-    let slice_ptr = &[0,1,2,3] as *const [i32];
+    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 {
+    let _ptr_to_unsized_transmute = unsafe { slice_ptr as *const [u16] };
-        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 {
+    let _usize_from_int_ptr_transmute = unsafe { ptr_i32 as usize };
-        ptr_i32 as usize
-    };
     let _usize_from_int_ptr = ptr_i32 as usize;
 
-    let array_ref: &[i32; 4] = &[1,2,3,4];
+    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 {
+    let _array_ptr_transmute = unsafe { array_ref as *const [i32; 4] };
-        array_ref as *const [i32; 4]
-    };
     let _array_ptr = array_ref as *const [i32; 4];
 
-    fn foo(_: usize) -> u8 { 42 }
+    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 {
+    let _usize_ptr_transmute = unsafe { foo as *const usize };
-        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 {
+    let _usize_from_fn_ptr_transmute = unsafe { foo as usize };
-        foo as usize
-    };
     let _usize_from_fn_ptr = foo as *const usize;
 }
 

tests/ui/transmutes_expressible_as_ptr_casts.rs

@@ -9,60 +9,48 @@
 
 use std::mem::{size_of, transmute};
 
-// rustc_typeck::check::cast contains documentation about when a cast `e as U` is 
+// 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 {
+    let _ptr_i32_transmute = unsafe { transmute::<usize, *const i32>(usize::MAX) };
-        transmute::<usize, *const i32>(usize::MAX)
-    };
     let ptr_i32 = usize::MAX as *const i32;
 
     // e has type *T, U is *U_0, and either U_0: Sized ...
-    let _ptr_i8_transmute = unsafe {
+    let _ptr_i8_transmute = unsafe { transmute::<*const i32, *const i8>(ptr_i32) };
-        transmute::<*const i32, *const i8>(ptr_i32)
-    };
     let _ptr_i8 = ptr_i32 as *const i8;
 
-    let slice_ptr = &[0,1,2,3] as *const [i32];
+    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 {
+    let _ptr_to_unsized_transmute = unsafe { transmute::<*const [i32], *const [u16]>(slice_ptr) };
-        transmute::<*const [i32], *const [u16]>(slice_ptr)
-    };
     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 {
+    let _usize_from_int_ptr_transmute = unsafe { transmute::<*const i32, usize>(ptr_i32) };
-        transmute::<*const i32, usize>(ptr_i32)
-    };
     let _usize_from_int_ptr = ptr_i32 as usize;
 
-    let array_ref: &[i32; 4] = &[1,2,3,4];
+    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 {
+    let _array_ptr_transmute = unsafe { transmute::<&[i32; 4], *const [i32; 4]>(array_ref) };
-        transmute::<&[i32; 4], *const [i32; 4]>(array_ref)
-    };
     let _array_ptr = array_ref as *const [i32; 4];
 
-    fn foo(_: usize) -> u8 { 42 }
+    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 {
+    let _usize_ptr_transmute = unsafe { transmute::<fn(usize) -> u8, *const usize>(foo) };
-        transmute::<fn(usize) -> u8, *const usize>(foo)
-    };
     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 {
+    let _usize_from_fn_ptr_transmute = unsafe { transmute::<fn(usize) -> u8, usize>(foo) };
-        transmute::<fn(usize) -> u8, usize>(foo)
-    };
     let _usize_from_fn_ptr = foo as *const usize;
 }
 

tests/ui/transmutes_expressible_as_ptr_casts.stderr

@@ -1,53 +1,53 @@
 error: transmute from an integer to a pointer
-  --> $DIR/transmutes_expressible_as_ptr_casts.rs:20:9
+  --> $DIR/transmutes_expressible_as_ptr_casts.rs:19:39
    |
-LL |         transmute::<usize, *const i32>(usize::MAX)
+LL |     let _ptr_i32_transmute = unsafe { transmute::<usize, *const i32>(usize::MAX) };
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `usize::MAX as *const i32`
+   |                                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `usize::MAX as *const i32`
    |
    = note: `-D clippy::useless-transmute` implied by `-D warnings`
 
 error: transmute from a pointer to a pointer
-  --> $DIR/transmutes_expressible_as_ptr_casts.rs:26:9
+  --> $DIR/transmutes_expressible_as_ptr_casts.rs:23:38
    |
-LL |         transmute::<*const i32, *const i8>(ptr_i32)
+LL |     let _ptr_i8_transmute = unsafe { transmute::<*const i32, *const i8>(ptr_i32) };
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `ptr_i32 as *const i8`
+   |                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `ptr_i32 as *const i8`
    |
    = note: `-D clippy::transmute-ptr-to-ptr` implied by `-D warnings`
 
 error: transmute from a pointer to a pointer
-  --> $DIR/transmutes_expressible_as_ptr_casts.rs:34:9
+  --> $DIR/transmutes_expressible_as_ptr_casts.rs:29:46
    |
-LL |         transmute::<*const [i32], *const [u16]>(slice_ptr)
+LL |     let _ptr_to_unsized_transmute = unsafe { transmute::<*const [i32], *const [u16]>(slice_ptr) };
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `slice_ptr as *const [u16]`
+   |                                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `slice_ptr as *const [u16]`
 
 error: transmute from `*const i32` to `usize` which could be expressed as a pointer cast instead
-  --> $DIR/transmutes_expressible_as_ptr_casts.rs:42:9
+  --> $DIR/transmutes_expressible_as_ptr_casts.rs:35:50
    |
-LL |         transmute::<*const i32, usize>(ptr_i32)
+LL |     let _usize_from_int_ptr_transmute = unsafe { transmute::<*const i32, usize>(ptr_i32) };
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `ptr_i32 as usize`
+   |                                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `ptr_i32 as usize`
    |
    = note: `-D clippy::transmutes-expressible-as-ptr-casts` implied by `-D warnings`
 
 error: transmute from a reference to a pointer
-  --> $DIR/transmutes_expressible_as_ptr_casts.rs:50:9
+  --> $DIR/transmutes_expressible_as_ptr_casts.rs:41:41
    |
-LL |         transmute::<&[i32; 4], *const [i32; 4]>(array_ref)
+LL |     let _array_ptr_transmute = unsafe { transmute::<&[i32; 4], *const [i32; 4]>(array_ref) };
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `array_ref as *const [i32; 4]`
+   |                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `array_ref as *const [i32; 4]`
 
 error: transmute from `fn(usize) -> u8 {main::foo}` to `*const usize` which could be expressed as a pointer cast instead
-  --> $DIR/transmutes_expressible_as_ptr_casts.rs:58:9
+  --> $DIR/transmutes_expressible_as_ptr_casts.rs:49:41
    |
-LL |         transmute::<fn(usize) -> u8, *const usize>(foo)
+LL |     let _usize_ptr_transmute = unsafe { transmute::<fn(usize) -> u8, *const usize>(foo) };
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `foo as *const usize`
+   |                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `foo as *const usize`
 
 error: transmute from `fn(usize) -> u8 {main::foo}` to `usize` which could be expressed as a pointer cast instead
-  --> $DIR/transmutes_expressible_as_ptr_casts.rs:64:9
+  --> $DIR/transmutes_expressible_as_ptr_casts.rs:53:49
    |
-LL |         transmute::<fn(usize) -> u8, usize>(foo)
+LL |     let _usize_from_fn_ptr_transmute = unsafe { transmute::<fn(usize) -> u8, usize>(foo) };
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `foo as usize`
+   |                                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `foo as usize`
 
 error: transmute from a reference to a pointer
-  --> $DIR/transmutes_expressible_as_ptr_casts.rs:77:14
+  --> $DIR/transmutes_expressible_as_ptr_casts.rs:65:14
    |
 LL |     unsafe { transmute::<&[i32; 1], *const u8>(in_param) }
    |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `in_param as *const [i32; 1] as *const u8`