Auto merge of #115698 - gurry:115143-ice-normalization-error, r=compiler-errors

Fix ICE in improper_ctypes_definitions lint

Fix #115143

Author: bors

compiler/rustc_lint/src/types.rs

@@ -917,8 +917,8 @@ pub(crate) fn repr_nullable_ptr<'tcx>(
         // At this point, the field's type is known to be nonnull and the parent enum is Option-like.
         // If the computed size for the field and the enum are different, the nonnull optimization isn't
         // being applied (and we've got a problem somewhere).
-        let compute_size_skeleton = |t| SizeSkeleton::compute(t, tcx, param_env).unwrap();
-        if !compute_size_skeleton(ty).same_size(compute_size_skeleton(field_ty)) {
+        let compute_size_skeleton = |t| SizeSkeleton::compute(t, tcx, param_env).ok();
+        if !compute_size_skeleton(ty)?.same_size(compute_size_skeleton(field_ty)?) {
             bug!("improper_ctypes: Option nonnull optimization not applied?");
         }
 

tests/ui/lint/lint-ctypes-94223.rs

@@ -24,6 +24,13 @@ enum BadUnion {
 type Foo = extern "C" fn([u8]);
 //~^ ERROR `extern` fn uses type `[u8]`, which is not FFI-safe
 
+pub trait FooTrait {
+    type FooType;
+}
+
+pub type Foo2<T> = extern "C" fn(Option<&<T as FooTrait>::FooType>);
+//~^ ERROR `extern` fn uses type `Option<&<T as FooTrait>::FooType>`, which is not FFI-safe
+
 pub struct FfiUnsafe;
 
 #[allow(improper_ctypes_definitions)]

tests/ui/lint/lint-ctypes-94223.stderr

@@ -66,61 +66,70 @@ LL | type Foo = extern "C" fn([u8]);
    = help: consider using a raw pointer instead
    = note: slices have no C equivalent
 
+error: `extern` fn uses type `Option<&<T as FooTrait>::FooType>`, which is not FFI-safe
+  --> $DIR/lint-ctypes-94223.rs:31:20
+   |
+LL | pub type Foo2<T> = extern "C" fn(Option<&<T as FooTrait>::FooType>);
+   |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
+   |
+   = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
+   = note: enum has no representation hint
+
 error: `extern` fn uses type `FfiUnsafe`, which is not FFI-safe
-  --> $DIR/lint-ctypes-94223.rs:34:17
+  --> $DIR/lint-ctypes-94223.rs:41:17
    |
 LL | pub static BAD: extern "C" fn(FfiUnsafe) = f;
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
    |
    = help: consider adding a `#[repr(C)]` or `#[repr(transparent)]` attribute to this struct
    = note: this struct has unspecified layout
 note: the type is defined here
-  --> $DIR/lint-ctypes-94223.rs:27:1
+  --> $DIR/lint-ctypes-94223.rs:34:1
    |
 LL | pub struct FfiUnsafe;
    | ^^^^^^^^^^^^^^^^^^^^
 
 error: `extern` fn uses type `FfiUnsafe`, which is not FFI-safe
-  --> $DIR/lint-ctypes-94223.rs:37:30
+  --> $DIR/lint-ctypes-94223.rs:44:30
    |
 LL | pub static BAD_TWICE: Result<extern "C" fn(FfiUnsafe), extern "C" fn(FfiUnsafe)> = Ok(f);
    |                              ^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
    |
    = help: consider adding a `#[repr(C)]` or `#[repr(transparent)]` attribute to this struct
    = note: this struct has unspecified layout
 note: the type is defined here
-  --> $DIR/lint-ctypes-94223.rs:27:1
+  --> $DIR/lint-ctypes-94223.rs:34:1
    |
 LL | pub struct FfiUnsafe;
    | ^^^^^^^^^^^^^^^^^^^^
 
 error: `extern` fn uses type `FfiUnsafe`, which is not FFI-safe
-  --> $DIR/lint-ctypes-94223.rs:37:56
+  --> $DIR/lint-ctypes-94223.rs:44:56
    |
 LL | pub static BAD_TWICE: Result<extern "C" fn(FfiUnsafe), extern "C" fn(FfiUnsafe)> = Ok(f);
    |                                                        ^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
    |
    = help: consider adding a `#[repr(C)]` or `#[repr(transparent)]` attribute to this struct
    = note: this struct has unspecified layout
 note: the type is defined here
-  --> $DIR/lint-ctypes-94223.rs:27:1
+  --> $DIR/lint-ctypes-94223.rs:34:1
    |
 LL | pub struct FfiUnsafe;
    | ^^^^^^^^^^^^^^^^^^^^
 
 error: `extern` fn uses type `FfiUnsafe`, which is not FFI-safe
-  --> $DIR/lint-ctypes-94223.rs:41:22
+  --> $DIR/lint-ctypes-94223.rs:48:22
    |
 LL | pub const BAD_CONST: extern "C" fn(FfiUnsafe) = f;
    |                      ^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
    |
    = help: consider adding a `#[repr(C)]` or `#[repr(transparent)]` attribute to this struct
    = note: this struct has unspecified layout
 note: the type is defined here
-  --> $DIR/lint-ctypes-94223.rs:27:1
+  --> $DIR/lint-ctypes-94223.rs:34:1
    |
 LL | pub struct FfiUnsafe;
    | ^^^^^^^^^^^^^^^^^^^^
 
-error: aborting due to 11 previous errors
+error: aborting due to 12 previous errors