lint/ctypes: check other types for ext. fn-ptr ty

Extend previous checks for external ABI fn-ptrs to use in internal
statics, constants, type aliases and algebraic data types.

Signed-off-by: David Wood <david.wood@huawei.com>

3 files changed, 127 insertions, 1 deletions

diff --git a/tests/ui/hashmap/hashmap-memory.rs b/tests/ui/hashmap/hashmap-memory.rs
index 87f8b6ad573..bd364b349e2 100644
--- a/tests/ui/hashmap/hashmap-memory.rs
+++ b/tests/ui/hashmap/hashmap-memory.rs
@@ -1,5 +1,6 @@
 // run-pass
 
+#![allow(improper_ctypes_definitions)]
 #![allow(non_camel_case_types)]
 #![allow(dead_code)]
 #![allow(unused_mut)]
diff --git a/tests/ui/lint/lint-ctypes-94223.rs b/tests/ui/lint/lint-ctypes-94223.rs
index 98ccbd23a9e..70dd2a71f26 100644
--- a/tests/ui/lint/lint-ctypes-94223.rs
+++ b/tests/ui/lint/lint-ctypes-94223.rs
@@ -7,3 +7,36 @@ pub fn bad(f: extern "C" fn([u8])) {}
 pub fn bad_twice(f: Result<extern "C" fn([u8]), extern "C" fn([u8])>) {}
 //~^ ERROR `extern` fn uses type `[u8]`, which is not FFI-safe
 //~^^ ERROR `extern` fn uses type `[u8]`, which is not FFI-safe
+
+struct BadStruct(extern "C" fn([u8]));
+//~^ ERROR `extern` fn uses type `[u8]`, which is not FFI-safe
+
+enum BadEnum {
+    A(extern "C" fn([u8])),
+    //~^ ERROR `extern` fn uses type `[u8]`, which is not FFI-safe
+}
+
+enum BadUnion {
+    A(extern "C" fn([u8])),
+    //~^ ERROR `extern` fn uses type `[u8]`, which is not FFI-safe
+}
+
+type Foo = extern "C" fn([u8]);
+//~^ ERROR `extern` fn uses type `[u8]`, which is not FFI-safe
+
+pub struct FfiUnsafe;
+
+#[allow(improper_ctypes_definitions)]
+extern "C" fn f(_: FfiUnsafe) {
+    unimplemented!()
+}
+
+pub static BAD: extern "C" fn(FfiUnsafe) = f;
+//~^ ERROR `extern` fn uses type `FfiUnsafe`, which is not FFI-safe
+
+pub static BAD_TWICE: Result<extern "C" fn(FfiUnsafe), extern "C" fn(FfiUnsafe)> = Ok(f);
+//~^ ERROR `extern` fn uses type `FfiUnsafe`, which is not FFI-safe
+//~^^ ERROR `extern` fn uses type `FfiUnsafe`, which is not FFI-safe
+
+pub const BAD_CONST: extern "C" fn(FfiUnsafe) = f;
+//~^ ERROR `extern` fn uses type `FfiUnsafe`, which is not FFI-safe
diff --git a/tests/ui/lint/lint-ctypes-94223.stderr b/tests/ui/lint/lint-ctypes-94223.stderr
index e05d6197cb4..49e64ed5140 100644
--- a/tests/ui/lint/lint-ctypes-94223.stderr
+++ b/tests/ui/lint/lint-ctypes-94223.stderr
@@ -30,5 +30,97 @@ LL | pub fn bad_twice(f: Result<extern "C" fn([u8]), extern "C" fn([u8])>) {}
    = help: consider using a raw pointer instead
    = note: slices have no C equivalent
 
-error: aborting due to 3 previous errors
+error: `extern` fn uses type `[u8]`, which is not FFI-safe
+  --> $DIR/lint-ctypes-94223.rs:11:18
+   |
+LL | struct BadStruct(extern "C" fn([u8]));
+   |                  ^^^^^^^^^^^^^^^^^^^ not FFI-safe
+   |
+   = help: consider using a raw pointer instead
+   = note: slices have no C equivalent
+
+error: `extern` fn uses type `[u8]`, which is not FFI-safe
+  --> $DIR/lint-ctypes-94223.rs:15:7
+   |
+LL |     A(extern "C" fn([u8])),
+   |       ^^^^^^^^^^^^^^^^^^^ not FFI-safe
+   |
+   = help: consider using a raw pointer instead
+   = note: slices have no C equivalent
+
+error: `extern` fn uses type `[u8]`, which is not FFI-safe
+  --> $DIR/lint-ctypes-94223.rs:20:7
+   |
+LL |     A(extern "C" fn([u8])),
+   |       ^^^^^^^^^^^^^^^^^^^ not FFI-safe
+   |
+   = help: consider using a raw pointer instead
+   = note: slices have no C equivalent
+
+error: `extern` fn uses type `[u8]`, which is not FFI-safe
+  --> $DIR/lint-ctypes-94223.rs:24:12
+   |
+LL | type Foo = extern "C" fn([u8]);
+   |            ^^^^^^^^^^^^^^^^^^^ not FFI-safe
+   |
+   = help: consider using a raw pointer instead
+   = note: slices have no C equivalent
+
+error: `extern` fn uses type `FfiUnsafe`, which is not FFI-safe
+  --> $DIR/lint-ctypes-94223.rs:34:17
+   |
+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
+   |
+LL | pub struct FfiUnsafe;
+   | ^^^^^^^^^^^^^^^^^^^^
+
+error: `extern` fn uses type `FfiUnsafe`, which is not FFI-safe
+  --> $DIR/lint-ctypes-94223.rs:37:30
+   |
+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
+   |
+LL | pub struct FfiUnsafe;
+   | ^^^^^^^^^^^^^^^^^^^^
+
+error: `extern` fn uses type `FfiUnsafe`, which is not FFI-safe
+  --> $DIR/lint-ctypes-94223.rs:37:56
+   |
+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
+   |
+LL | pub struct FfiUnsafe;
+   | ^^^^^^^^^^^^^^^^^^^^
+
+error: `extern` fn uses type `FfiUnsafe`, which is not FFI-safe
+  --> $DIR/lint-ctypes-94223.rs:41:22
+   |
+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
+   |
+LL | pub struct FfiUnsafe;
+   | ^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 11 previous errors