Add ffi tests for pattern types

4 files changed, 185 insertions, 22 deletions

diff --git a/tests/ui/lint/clashing-extern-fn.rs b/tests/ui/lint/clashing-extern-fn.rs
index 9bbb20246df..0464299348b 100644
--- a/tests/ui/lint/clashing-extern-fn.rs
+++ b/tests/ui/lint/clashing-extern-fn.rs
@@ -1,7 +1,7 @@
 //@ check-pass
 //@ aux-build:external_extern_fn.rs
 #![crate_type = "lib"]
-
+#![feature(pattern_type_macro, pattern_types)]
 mod redeclared_different_signature {
     mod a {
         extern "C" {
@@ -490,3 +490,42 @@ mod hidden_niche {
         }
     }
 }
+
+mod pattern_types {
+    mod a {
+        use std::pat::pattern_type;
+        #[repr(transparent)]
+        struct NonZeroUsize(pattern_type!(usize is 1..));
+        extern "C" {
+            fn pt_non_zero_usize() -> pattern_type!(usize is 1..);
+            //~^ WARN not FFI-safe
+            fn pt_non_zero_usize_opt() -> Option<pattern_type!(usize is 1..)>;
+            //~^ WARN not FFI-safe
+            fn pt_non_zero_usize_opt_full_range() -> Option<pattern_type!(usize is 0..)>;
+            //~^ WARN not FFI-safe
+            fn pt_non_null_ptr() -> pattern_type!(usize is 1..);
+            //~^ WARN not FFI-safe
+            fn pt_non_zero_usize_wrapper() -> NonZeroUsize;
+            //~^ WARN not FFI-safe
+            fn pt_non_zero_usize_wrapper_opt() -> Option<NonZeroUsize>;
+            //~^ WARN not FFI-safe
+        }
+    }
+    mod b {
+        extern "C" {
+            // If there's a clash in either of these cases you're either gaining an incorrect
+            // invariant that the value is non-zero, or you're missing out on that invariant. Both
+            // cases are warning for, from both a caller-convenience and optimisation perspective.
+            fn pt_non_zero_usize() -> usize;
+            //~^ WARN `pt_non_zero_usize` redeclared with a different signature
+            fn pt_non_zero_usize_opt() -> usize;
+            //~^ WARN `pt_non_zero_usize_opt` redeclared with a different signature
+            fn pt_non_null_ptr() -> *const ();
+            //~^ WARN `pt_non_null_ptr` redeclared with a different signature
+            fn pt_non_zero_usize_wrapper() -> usize;
+            //~^ WARN `pt_non_zero_usize_wrapper` redeclared with a different signature
+            fn pt_non_zero_usize_wrapper_opt() -> usize;
+            //~^ WARN `pt_non_zero_usize_wrapper_opt` redeclared with a different signature
+        }
+    }
+}
diff --git a/tests/ui/lint/clashing-extern-fn.stderr b/tests/ui/lint/clashing-extern-fn.stderr
index 48dd1adbc1f..acf31a1f5dd 100644
--- a/tests/ui/lint/clashing-extern-fn.stderr
+++ b/tests/ui/lint/clashing-extern-fn.stderr
@@ -17,6 +17,60 @@ LL |             fn hidden_niche_unsafe_cell() -> Option<UnsafeCell<NonZero<usiz
    = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
    = note: enum has no representation hint
 
+warning: `extern` block uses type `(usize) is 1..=`, which is not FFI-safe
+  --> $DIR/clashing-extern-fn.rs:500:39
+   |
+LL |             fn pt_non_zero_usize() -> pattern_type!(usize is 1..);
+   |                                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
+   |
+   = help: consider using the base type instead
+   = note: pattern types have no C equivalent
+
+warning: `extern` block uses type `Option<(usize) is 1..=>`, which is not FFI-safe
+  --> $DIR/clashing-extern-fn.rs:502:43
+   |
+LL |             fn pt_non_zero_usize_opt() -> Option<pattern_type!(usize is 1..)>;
+   |                                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
+   |
+   = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
+   = note: enum has no representation hint
+
+warning: `extern` block uses type `Option<(usize) is 0..=>`, which is not FFI-safe
+  --> $DIR/clashing-extern-fn.rs:504:54
+   |
+LL |             fn pt_non_zero_usize_opt_full_range() -> Option<pattern_type!(usize is 0..)>;
+   |                                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
+   |
+   = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
+   = note: enum has no representation hint
+
+warning: `extern` block uses type `(usize) is 1..=`, which is not FFI-safe
+  --> $DIR/clashing-extern-fn.rs:506:37
+   |
+LL |             fn pt_non_null_ptr() -> pattern_type!(usize is 1..);
+   |                                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
+   |
+   = help: consider using the base type instead
+   = note: pattern types have no C equivalent
+
+warning: `extern` block uses type `(usize) is 1..=`, which is not FFI-safe
+  --> $DIR/clashing-extern-fn.rs:508:47
+   |
+LL |             fn pt_non_zero_usize_wrapper() -> NonZeroUsize;
+   |                                               ^^^^^^^^^^^^ not FFI-safe
+   |
+   = help: consider using the base type instead
+   = note: pattern types have no C equivalent
+
+warning: `extern` block uses type `Option<NonZeroUsize>`, which is not FFI-safe
+  --> $DIR/clashing-extern-fn.rs:510:51
+   |
+LL |             fn pt_non_zero_usize_wrapper_opt() -> Option<NonZeroUsize>;
+   |                                                   ^^^^^^^^^^^^^^^^^^^^ not FFI-safe
+   |
+   = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
+   = note: enum has no representation hint
+
 warning: `clash` redeclared with a different signature
   --> $DIR/clashing-extern-fn.rs:13:13
    |
@@ -258,5 +312,65 @@ LL |             fn hidden_niche_unsafe_cell() -> Option<UnsafeCell<NonZero<usiz
    = note: expected `unsafe extern "C" fn() -> usize`
               found `unsafe extern "C" fn() -> Option<UnsafeCell<NonZero<usize>>>`
 
-warning: 22 warnings emitted
+warning: `pt_non_zero_usize` redeclared with a different signature
+  --> $DIR/clashing-extern-fn.rs:519:13
+   |
+LL |             fn pt_non_zero_usize() -> pattern_type!(usize is 1..);
+   |             ------------------------------------------------------ `pt_non_zero_usize` previously declared here
+...
+LL |             fn pt_non_zero_usize() -> usize;
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this signature doesn't match the previous declaration
+   |
+   = note: expected `unsafe extern "C" fn() -> (usize) is 1..=`
+              found `unsafe extern "C" fn() -> usize`
+
+warning: `pt_non_zero_usize_opt` redeclared with a different signature
+  --> $DIR/clashing-extern-fn.rs:521:13
+   |
+LL |             fn pt_non_zero_usize_opt() -> Option<pattern_type!(usize is 1..)>;
+   |             ------------------------------------------------------------------ `pt_non_zero_usize_opt` previously declared here
+...
+LL |             fn pt_non_zero_usize_opt() -> usize;
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this signature doesn't match the previous declaration
+   |
+   = note: expected `unsafe extern "C" fn() -> Option<(usize) is 1..=>`
+              found `unsafe extern "C" fn() -> usize`
+
+warning: `pt_non_null_ptr` redeclared with a different signature
+  --> $DIR/clashing-extern-fn.rs:523:13
+   |
+LL |             fn pt_non_null_ptr() -> pattern_type!(usize is 1..);
+   |             ---------------------------------------------------- `pt_non_null_ptr` previously declared here
+...
+LL |             fn pt_non_null_ptr() -> *const ();
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this signature doesn't match the previous declaration
+   |
+   = note: expected `unsafe extern "C" fn() -> (usize) is 1..=`
+              found `unsafe extern "C" fn() -> *const ()`
+
+warning: `pt_non_zero_usize_wrapper` redeclared with a different signature
+  --> $DIR/clashing-extern-fn.rs:525:13
+   |
+LL |             fn pt_non_zero_usize_wrapper() -> NonZeroUsize;
+   |             ----------------------------------------------- `pt_non_zero_usize_wrapper` previously declared here
+...
+LL |             fn pt_non_zero_usize_wrapper() -> usize;
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this signature doesn't match the previous declaration
+   |
+   = note: expected `unsafe extern "C" fn() -> NonZeroUsize`
+              found `unsafe extern "C" fn() -> usize`
+
+warning: `pt_non_zero_usize_wrapper_opt` redeclared with a different signature
+  --> $DIR/clashing-extern-fn.rs:527:13
+   |
+LL |             fn pt_non_zero_usize_wrapper_opt() -> Option<NonZeroUsize>;
+   |             ----------------------------------------------------------- `pt_non_zero_usize_wrapper_opt` previously declared here
+...
+LL |             fn pt_non_zero_usize_wrapper_opt() -> usize;
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this signature doesn't match the previous declaration
+   |
+   = note: expected `unsafe extern "C" fn() -> Option<NonZeroUsize>`
+              found `unsafe extern "C" fn() -> usize`
+
+warning: 33 warnings emitted
 
diff --git a/tests/ui/lint/lint-ctypes-enum.rs b/tests/ui/lint/lint-ctypes-enum.rs
index 19af1de9576..0d19d5b5347 100644
--- a/tests/ui/lint/lint-ctypes-enum.rs
+++ b/tests/ui/lint/lint-ctypes-enum.rs
@@ -94,6 +94,7 @@ extern "C" {
     fn option_transparent_union(x: Option<TransparentUnion<num::NonZero<u8>>>);
     //~^ ERROR `extern` block uses type
     fn option_repr_rust(x: Option<Rust<num::NonZero<u8>>>); //~ ERROR `extern` block uses type
+    fn option_u8(x: Option<u8>); //~ ERROR `extern` block uses type
 
     fn result_ref_t(x: Result<&'static u8, ()>);
     fn result_fn_t(x: Result<extern "C" fn(), ()>);
diff --git a/tests/ui/lint/lint-ctypes-enum.stderr b/tests/ui/lint/lint-ctypes-enum.stderr
index 8e92e7e6946..a491bd19605 100644
--- a/tests/ui/lint/lint-ctypes-enum.stderr
+++ b/tests/ui/lint/lint-ctypes-enum.stderr
@@ -79,8 +79,17 @@ LL |     fn option_repr_rust(x: Option<Rust<num::NonZero<u8>>>);
    = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
    = note: enum has no representation hint
 
+error: `extern` block uses type `Option<u8>`, which is not FFI-safe
+  --> $DIR/lint-ctypes-enum.rs:97:21
+   |
+LL |     fn option_u8(x: Option<u8>);
+   |                     ^^^^^^^^^^ 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` block uses type `u128`, which is not FFI-safe
-  --> $DIR/lint-ctypes-enum.rs:106:33
+  --> $DIR/lint-ctypes-enum.rs:107:33
    |
 LL |     fn result_nonzero_u128_t(x: Result<num::NonZero<u128>, ()>);
    |                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
@@ -88,7 +97,7 @@ LL |     fn result_nonzero_u128_t(x: Result<num::NonZero<u128>, ()>);
    = note: 128-bit integers don't currently have a known stable ABI
 
 error: `extern` block uses type `i128`, which is not FFI-safe
-  --> $DIR/lint-ctypes-enum.rs:113:33
+  --> $DIR/lint-ctypes-enum.rs:114:33
    |
 LL |     fn result_nonzero_i128_t(x: Result<num::NonZero<i128>, ()>);
    |                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
@@ -96,7 +105,7 @@ LL |     fn result_nonzero_i128_t(x: Result<num::NonZero<i128>, ()>);
    = note: 128-bit integers don't currently have a known stable ABI
 
 error: `extern` block uses type `Result<TransparentUnion<NonZero<u8>>, ()>`, which is not FFI-safe
-  --> $DIR/lint-ctypes-enum.rs:118:38
+  --> $DIR/lint-ctypes-enum.rs:119:38
    |
 LL |     fn result_transparent_union_t(x: Result<TransparentUnion<num::NonZero<u8>>, ()>);
    |                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
@@ -105,7 +114,7 @@ LL |     fn result_transparent_union_t(x: Result<TransparentUnion<num::NonZero<u
    = note: enum has no representation hint
 
 error: `extern` block uses type `Result<Rust<NonZero<u8>>, ()>`, which is not FFI-safe
-  --> $DIR/lint-ctypes-enum.rs:120:30
+  --> $DIR/lint-ctypes-enum.rs:121:30
    |
 LL |     fn result_repr_rust_t(x: Result<Rust<num::NonZero<u8>>, ()>);
    |                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
@@ -114,7 +123,7 @@ LL |     fn result_repr_rust_t(x: Result<Rust<num::NonZero<u8>>, ()>);
    = note: enum has no representation hint
 
 error: `extern` block uses type `Result<NonZero<u8>, U>`, which is not FFI-safe
-  --> $DIR/lint-ctypes-enum.rs:124:51
+  --> $DIR/lint-ctypes-enum.rs:125:51
    |
 LL |     fn result_1zst_exhaustive_single_variant_t(x: Result<num::NonZero<u8>, U>);
    |                                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
@@ -123,7 +132,7 @@ LL |     fn result_1zst_exhaustive_single_variant_t(x: Result<num::NonZero<u8>,
    = note: enum has no representation hint
 
 error: `extern` block uses type `Result<NonZero<u8>, B>`, which is not FFI-safe
-  --> $DIR/lint-ctypes-enum.rs:126:53
+  --> $DIR/lint-ctypes-enum.rs:127:53
    |
 LL |     fn result_1zst_exhaustive_multiple_variant_t(x: Result<num::NonZero<u8>, B>);
    |                                                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
@@ -132,7 +141,7 @@ LL |     fn result_1zst_exhaustive_multiple_variant_t(x: Result<num::NonZero<u8>
    = note: enum has no representation hint
 
 error: `extern` block uses type `Result<NonZero<u8>, NonExhaustive>`, which is not FFI-safe
-  --> $DIR/lint-ctypes-enum.rs:128:51
+  --> $DIR/lint-ctypes-enum.rs:129:51
    |
 LL |     fn result_1zst_non_exhaustive_no_variant_t(x: Result<num::NonZero<u8>, NonExhaustive>);
    |                                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
@@ -141,7 +150,7 @@ LL |     fn result_1zst_non_exhaustive_no_variant_t(x: Result<num::NonZero<u8>,
    = note: enum has no representation hint
 
 error: `extern` block uses type `Result<NonZero<u8>, Field>`, which is not FFI-safe
-  --> $DIR/lint-ctypes-enum.rs:131:49
+  --> $DIR/lint-ctypes-enum.rs:132:49
    |
 LL |     fn result_1zst_exhaustive_single_field_t(x: Result<num::NonZero<u8>, Field>);
    |                                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
@@ -150,7 +159,7 @@ LL |     fn result_1zst_exhaustive_single_field_t(x: Result<num::NonZero<u8>, Fi
    = note: enum has no representation hint
 
 error: `extern` block uses type `Result<Result<(), NonZero<u8>>, ()>`, which is not FFI-safe
-  --> $DIR/lint-ctypes-enum.rs:133:30
+  --> $DIR/lint-ctypes-enum.rs:134:30
    |
 LL |     fn result_cascading_t(x: Result<Result<(), num::NonZero<u8>>, ()>);
    |                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
@@ -159,7 +168,7 @@ LL |     fn result_cascading_t(x: Result<Result<(), num::NonZero<u8>>, ()>);
    = note: enum has no representation hint
 
 error: `extern` block uses type `u128`, which is not FFI-safe
-  --> $DIR/lint-ctypes-enum.rs:144:33
+  --> $DIR/lint-ctypes-enum.rs:145:33
    |
 LL |     fn result_nonzero_u128_e(x: Result<(), num::NonZero<u128>>);
    |                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
@@ -167,7 +176,7 @@ LL |     fn result_nonzero_u128_e(x: Result<(), num::NonZero<u128>>);
    = note: 128-bit integers don't currently have a known stable ABI
 
 error: `extern` block uses type `i128`, which is not FFI-safe
-  --> $DIR/lint-ctypes-enum.rs:151:33
+  --> $DIR/lint-ctypes-enum.rs:152:33
    |
 LL |     fn result_nonzero_i128_e(x: Result<(), num::NonZero<i128>>);
    |                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
@@ -175,7 +184,7 @@ LL |     fn result_nonzero_i128_e(x: Result<(), num::NonZero<i128>>);
    = note: 128-bit integers don't currently have a known stable ABI
 
 error: `extern` block uses type `Result<(), TransparentUnion<NonZero<u8>>>`, which is not FFI-safe
-  --> $DIR/lint-ctypes-enum.rs:156:38
+  --> $DIR/lint-ctypes-enum.rs:157:38
    |
 LL |     fn result_transparent_union_e(x: Result<(), TransparentUnion<num::NonZero<u8>>>);
    |                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
@@ -184,7 +193,7 @@ LL |     fn result_transparent_union_e(x: Result<(), TransparentUnion<num::NonZe
    = note: enum has no representation hint
 
 error: `extern` block uses type `Result<(), Rust<NonZero<u8>>>`, which is not FFI-safe
-  --> $DIR/lint-ctypes-enum.rs:158:30
+  --> $DIR/lint-ctypes-enum.rs:159:30
    |
 LL |     fn result_repr_rust_e(x: Result<(), Rust<num::NonZero<u8>>>);
    |                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
@@ -193,7 +202,7 @@ LL |     fn result_repr_rust_e(x: Result<(), Rust<num::NonZero<u8>>>);
    = note: enum has no representation hint
 
 error: `extern` block uses type `Result<U, NonZero<u8>>`, which is not FFI-safe
-  --> $DIR/lint-ctypes-enum.rs:162:51
+  --> $DIR/lint-ctypes-enum.rs:163:51
    |
 LL |     fn result_1zst_exhaustive_single_variant_e(x: Result<U, num::NonZero<u8>>);
    |                                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
@@ -202,7 +211,7 @@ LL |     fn result_1zst_exhaustive_single_variant_e(x: Result<U, num::NonZero<u8
    = note: enum has no representation hint
 
 error: `extern` block uses type `Result<B, NonZero<u8>>`, which is not FFI-safe
-  --> $DIR/lint-ctypes-enum.rs:164:53
+  --> $DIR/lint-ctypes-enum.rs:165:53
    |
 LL |     fn result_1zst_exhaustive_multiple_variant_e(x: Result<B, num::NonZero<u8>>);
    |                                                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
@@ -211,7 +220,7 @@ LL |     fn result_1zst_exhaustive_multiple_variant_e(x: Result<B, num::NonZero<
    = note: enum has no representation hint
 
 error: `extern` block uses type `Result<NonExhaustive, NonZero<u8>>`, which is not FFI-safe
-  --> $DIR/lint-ctypes-enum.rs:166:51
+  --> $DIR/lint-ctypes-enum.rs:167:51
    |
 LL |     fn result_1zst_non_exhaustive_no_variant_e(x: Result<NonExhaustive, num::NonZero<u8>>);
    |                                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
@@ -220,7 +229,7 @@ LL |     fn result_1zst_non_exhaustive_no_variant_e(x: Result<NonExhaustive, num
    = note: enum has no representation hint
 
 error: `extern` block uses type `Result<Field, NonZero<u8>>`, which is not FFI-safe
-  --> $DIR/lint-ctypes-enum.rs:169:49
+  --> $DIR/lint-ctypes-enum.rs:170:49
    |
 LL |     fn result_1zst_exhaustive_single_field_e(x: Result<Field, num::NonZero<u8>>);
    |                                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
@@ -229,7 +238,7 @@ LL |     fn result_1zst_exhaustive_single_field_e(x: Result<Field, num::NonZero<
    = note: enum has no representation hint
 
 error: `extern` block uses type `Result<(), Result<(), NonZero<u8>>>`, which is not FFI-safe
-  --> $DIR/lint-ctypes-enum.rs:171:30
+  --> $DIR/lint-ctypes-enum.rs:172:30
    |
 LL |     fn result_cascading_e(x: Result<(), Result<(), num::NonZero<u8>>>);
    |                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
@@ -238,7 +247,7 @@ LL |     fn result_cascading_e(x: Result<(), Result<(), num::NonZero<u8>>>);
    = note: enum has no representation hint
 
 error: `extern` block uses type `Result<(), ()>`, which is not FFI-safe
-  --> $DIR/lint-ctypes-enum.rs:173:27
+  --> $DIR/lint-ctypes-enum.rs:174:27
    |
 LL |     fn result_unit_t_e(x: Result<(), ()>);
    |                           ^^^^^^^^^^^^^^ not FFI-safe
@@ -246,5 +255,5 @@ LL |     fn result_unit_t_e(x: Result<(), ()>);
    = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
    = note: enum has no representation hint
 
-error: aborting due to 26 previous errors
+error: aborting due to 27 previous errors