Add new tests and bless old tests

src/test/ui/macros/issue-68060.stderr

@@ -1,11 +1,14 @@
-error: `#[target_feature(..)]` can only be applied to `unsafe` functions
+error[E0658]: `#[target_feature(..)]` can only be applied to `unsafe` functions
   --> $DIR/issue-68060.rs:6:13
    |
 LL |             #[target_feature(enable = "")]
-   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ can only be applied to `unsafe` functions
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 ...
 LL |             |_| (),
    |             ------ not an `unsafe` function
+   |
+   = note: see issue #69098 <https://github.com/rust-lang/rust/issues/69098> for more information
+   = help: add `#![feature(target_feature_11)]` to the crate attributes to enable
 
 error: the feature named `` is not valid for this target
   --> $DIR/issue-68060.rs:6:30
@@ -21,4 +24,5 @@ LL |             #[track_caller]
 
 error: aborting due to 3 previous errors
 
-For more information about this error, try `rustc --explain E0737`.
+Some errors have detailed explanations: E0658, E0737.
+For more information about an error, try `rustc --explain E0658`.

src/test/ui/rfcs/rfc-2396-target_feature-11/check-pass.rs

@@ -0,0 +1,50 @@
+// Tests the new rules added by RFC 2396, including:
+// - applying `#[target_feature]` to safe functions is allowed
+// - calling functions with `#[target_feature]` is allowed in
+//   functions which have (at least) the same features
+// - calling functions with `#[target_feature]` is allowed in
+//   unsafe contexts
+// - functions with `#[target_feature]` can coerce to unsafe fn pointers
+
+// check-pass
+// only-x86_64
+
+#![feature(target_feature_11)]
+
+#[target_feature(enable = "sse2")]
+const fn sse2() {}
+
+#[cfg(target_feature = "sse2")]
+const SSE2_ONLY: () = unsafe {
+    sse2();
+};
+
+#[target_feature(enable = "sse2")]
+fn also_sse2() {
+    sse2();
+}
+
+#[target_feature(enable = "sse2")]
+#[target_feature(enable = "avx")]
+fn sse2_and_avx() {
+    sse2();
+}
+
+struct Foo;
+
+impl Foo {
+    #[target_feature(enable = "sse2")]
+    fn sse2(&self) {
+        sse2();
+    }
+}
+
+fn main() {
+    if cfg!(target_feature = "sse2") {
+        unsafe {
+            sse2();
+            Foo.sse2();
+        }
+    }
+    let sse2_ptr: unsafe fn() = sse2;
+}

src/test/ui/rfcs/rfc-2396-target_feature-11/feature-gate-target_feature_11.rs

@@ -0,0 +1,6 @@
+// only-x86_64
+
+#[target_feature(enable = "sse2")] //~ ERROR can only be applied to `unsafe` functions
+fn foo() {}
+
+fn main() {}

src/test/ui/rfcs/rfc-2396-target_feature-11/feature-gate-target_feature_11.stderr

@@ -0,0 +1,14 @@
+error[E0658]: `#[target_feature(..)]` can only be applied to `unsafe` functions
+  --> $DIR/feature-gate-target_feature_11.rs:3:1
+   |
+LL | #[target_feature(enable = "sse2")]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | fn foo() {}
+   | ----------- not an `unsafe` function
+   |
+   = note: see issue #69098 <https://github.com/rust-lang/rust/issues/69098> for more information
+   = help: add `#![feature(target_feature_11)]` to the crate attributes to enable
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0658`.

src/test/ui/rfcs/rfc-2396-target_feature-11/fn-ptr.rs

@@ -0,0 +1,10 @@
+// only-x86_64
+
+#![feature(target_feature_11)]
+
+#[target_feature(enable = "sse2")]
+fn foo() {}
+
+fn main() {
+    let foo: fn() = foo; //~ ERROR mismatched types
+}

src/test/ui/rfcs/rfc-2396-target_feature-11/fn-ptr.stderr

@@ -0,0 +1,18 @@
+error[E0308]: mismatched types
+  --> $DIR/fn-ptr.rs:9:21
+   |
+LL | #[target_feature(enable = "sse2")]
+   | ---------------------------------- `#[target_feature]` added here
+...
+LL |     let foo: fn() = foo;
+   |              ----   ^^^ cannot coerce functions with `#[target_feature]` to safe function pointers
+   |              |
+   |              expected due to this
+   |
+   = note: expected fn pointer `fn()`
+                 found fn item `fn() {foo}`
+   = note: functions with `#[target_feature]` can only be coerced to `unsafe` function pointers
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.

src/test/ui/rfcs/rfc-2396-target_feature-11/safe-calls.rs

@@ -0,0 +1,47 @@
+// only-x86_64
+
+#![feature(target_feature_11)]
+
+#[target_feature(enable = "sse2")]
+const fn sse2() {}
+
+#[target_feature(enable = "avx")]
+#[target_feature(enable = "bmi2")]
+fn avx_bmi2() {}
+
+struct Quux;
+
+impl Quux {
+    #[target_feature(enable = "avx")]
+    #[target_feature(enable = "bmi2")]
+    fn avx_bmi2(&self) {}
+}
+
+fn foo() {
+    sse2();              //~ ERROR call to function with `#[target_feature]` is unsafe
+    avx_bmi2();          //~ ERROR call to function with `#[target_feature]` is unsafe
+    Quux.avx_bmi2();     //~ ERROR call to function with `#[target_feature]` is unsafe
+}
+
+#[target_feature(enable = "sse2")]
+fn bar() {
+    avx_bmi2();          //~ ERROR call to function with `#[target_feature]` is unsafe
+    Quux.avx_bmi2();     //~ ERROR call to function with `#[target_feature]` is unsafe
+}
+
+#[target_feature(enable = "avx")]
+fn baz() {
+    sse2();              //~ ERROR call to function with `#[target_feature]` is unsafe
+    avx_bmi2();          //~ ERROR call to function with `#[target_feature]` is unsafe
+    Quux.avx_bmi2();     //~ ERROR call to function with `#[target_feature]` is unsafe
+}
+
+#[target_feature(enable = "avx")]
+#[target_feature(enable = "bmi2")]
+fn qux() {
+    sse2();              //~ ERROR call to function with `#[target_feature]` is unsafe
+}
+
+const name: () = sse2(); //~ ERROR call to function with `#[target_feature]` is unsafe
+
+fn main() {}

src/test/ui/rfcs/rfc-2396-target_feature-11/safe-calls.stderr

@@ -0,0 +1,83 @@
+error[E0133]: call to function with `#[target_feature]` is unsafe and requires unsafe function or block
+  --> $DIR/safe-calls.rs:21:5
+   |
+LL |     sse2();
+   |     ^^^^^^ call to function with `#[target_feature]`
+   |
+   = note: can only be called if the required target features are available
+
+error[E0133]: call to function with `#[target_feature]` is unsafe and requires unsafe function or block
+  --> $DIR/safe-calls.rs:22:5
+   |
+LL |     avx_bmi2();
+   |     ^^^^^^^^^^ call to function with `#[target_feature]`
+   |
+   = note: can only be called if the required target features are available
+
+error[E0133]: call to function with `#[target_feature]` is unsafe and requires unsafe function or block
+  --> $DIR/safe-calls.rs:23:5
+   |
+LL |     Quux.avx_bmi2();
+   |     ^^^^^^^^^^^^^^^ call to function with `#[target_feature]`
+   |
+   = note: can only be called if the required target features are available
+
+error[E0133]: call to function with `#[target_feature]` is unsafe and requires unsafe function or block
+  --> $DIR/safe-calls.rs:28:5
+   |
+LL |     avx_bmi2();
+   |     ^^^^^^^^^^ call to function with `#[target_feature]`
+   |
+   = note: can only be called if the required target features are available
+
+error[E0133]: call to function with `#[target_feature]` is unsafe and requires unsafe function or block
+  --> $DIR/safe-calls.rs:29:5
+   |
+LL |     Quux.avx_bmi2();
+   |     ^^^^^^^^^^^^^^^ call to function with `#[target_feature]`
+   |
+   = note: can only be called if the required target features are available
+
+error[E0133]: call to function with `#[target_feature]` is unsafe and requires unsafe function or block
+  --> $DIR/safe-calls.rs:34:5
+   |
+LL |     sse2();
+   |     ^^^^^^ call to function with `#[target_feature]`
+   |
+   = note: can only be called if the required target features are available
+
+error[E0133]: call to function with `#[target_feature]` is unsafe and requires unsafe function or block
+  --> $DIR/safe-calls.rs:35:5
+   |
+LL |     avx_bmi2();
+   |     ^^^^^^^^^^ call to function with `#[target_feature]`
+   |
+   = note: can only be called if the required target features are available
+
+error[E0133]: call to function with `#[target_feature]` is unsafe and requires unsafe function or block
+  --> $DIR/safe-calls.rs:36:5
+   |
+LL |     Quux.avx_bmi2();
+   |     ^^^^^^^^^^^^^^^ call to function with `#[target_feature]`
+   |
+   = note: can only be called if the required target features are available
+
+error[E0133]: call to function with `#[target_feature]` is unsafe and requires unsafe function or block
+  --> $DIR/safe-calls.rs:42:5
+   |
+LL |     sse2();
+   |     ^^^^^^ call to function with `#[target_feature]`
+   |
+   = note: can only be called if the required target features are available
+
+error[E0133]: call to function with `#[target_feature]` is unsafe and requires unsafe function or block
+  --> $DIR/safe-calls.rs:45:18
+   |
+LL | const name: () = sse2();
+   |                  ^^^^^^ call to function with `#[target_feature]`
+   |
+   = note: can only be called if the required target features are available
+
+error: aborting due to 10 previous errors
+
+For more information about this error, try `rustc --explain E0133`.

src/test/ui/rfcs/rfc-2396-target_feature-11/trait-impl.rs

@@ -0,0 +1,21 @@
+// only-x86_64
+
+#![feature(target_feature_11)]
+
+trait Foo {
+    fn foo(&self);
+    unsafe fn unsf_foo(&self);
+}
+
+struct Bar;
+
+impl Foo for Bar {
+    #[target_feature(enable = "sse2")]
+    //~^ ERROR cannot be applied to safe trait method
+    fn foo(&self) {}
+
+    #[target_feature(enable = "sse2")]
+    unsafe fn unsf_foo(&self) {}
+}
+
+fn main() {}

src/test/ui/rfcs/rfc-2396-target_feature-11/trait-impl.stderr

@@ -0,0 +1,11 @@
+error: `#[target_feature(..)]` cannot be applied to safe trait method
+  --> $DIR/trait-impl.rs:13:5
+   |
+LL |     #[target_feature(enable = "sse2")]
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot be applied to safe trait method
+LL |
+LL |     fn foo(&self) {}
+   |     ---------------- not an `unsafe` function
+
+error: aborting due to previous error
+

src/test/ui/target-feature/invalid-attribute.rs

@@ -26,7 +26,7 @@ unsafe fn foo() {}
 
 #[target_feature(enable = "sse2")]
 //~^ ERROR `#[target_feature(..)]` can only be applied to `unsafe` functions
-//~| NOTE can only be applied to `unsafe` functions
+//~| NOTE see issue #69098
 fn bar() {}
 //~^ NOTE not an `unsafe` function
 
@@ -72,7 +72,7 @@ trait Quux {
 impl Quux for Foo {
     #[target_feature(enable = "sse2")]
     //~^ ERROR `#[target_feature(..)]` can only be applied to `unsafe` functions
-    //~| NOTE can only be applied to `unsafe` functions
+    //~| NOTE see issue #69098
     fn foo() {}
     //~^ NOTE not an `unsafe` function
 }
@@ -84,7 +84,7 @@ fn main() {
     }
     #[target_feature(enable = "sse2")]
     //~^ ERROR `#[target_feature(..)]` can only be applied to `unsafe` functions
-    //~| NOTE can only be applied to `unsafe` functions
+    //~| NOTE see issue #69098
     || {};
     //~^ NOTE not an `unsafe` function
 }

src/test/ui/target-feature/invalid-attribute.stderr

@@ -22,14 +22,17 @@ error: malformed `target_feature` attribute input
 LL | #[target_feature(disable = "baz")]
    |                  ^^^^^^^^^^^^^^^ help: must be of the form: `enable = ".."`
 
-error: `#[target_feature(..)]` can only be applied to `unsafe` functions
+error[E0658]: `#[target_feature(..)]` can only be applied to `unsafe` functions
   --> $DIR/invalid-attribute.rs:27:1
    |
 LL | #[target_feature(enable = "sse2")]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ can only be applied to `unsafe` functions
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 ...
 LL | fn bar() {}
    | ----------- not an `unsafe` function
+   |
+   = note: see issue #69098 <https://github.com/rust-lang/rust/issues/69098> for more information
+   = help: add `#![feature(target_feature_11)]` to the crate attributes to enable
 
 error: attribute should be applied to a function
   --> $DIR/invalid-attribute.rs:33:1
@@ -91,23 +94,30 @@ error: cannot use `#[inline(always)]` with `#[target_feature]`
 LL | #[inline(always)]
    | ^^^^^^^^^^^^^^^^^
 
-error: `#[target_feature(..)]` can only be applied to `unsafe` functions
+error[E0658]: `#[target_feature(..)]` can only be applied to `unsafe` functions
   --> $DIR/invalid-attribute.rs:85:5
    |
 LL |     #[target_feature(enable = "sse2")]
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ can only be applied to `unsafe` functions
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 ...
 LL |     || {};
    |     ----- not an `unsafe` function
+   |
+   = note: see issue #69098 <https://github.com/rust-lang/rust/issues/69098> for more information
+   = help: add `#![feature(target_feature_11)]` to the crate attributes to enable
 
-error: `#[target_feature(..)]` can only be applied to `unsafe` functions
+error[E0658]: `#[target_feature(..)]` can only be applied to `unsafe` functions
   --> $DIR/invalid-attribute.rs:73:5
    |
 LL |     #[target_feature(enable = "sse2")]
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ can only be applied to `unsafe` functions
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 ...
 LL |     fn foo() {}
    |     ----------- not an `unsafe` function
+   |
+   = note: see issue #69098 <https://github.com/rust-lang/rust/issues/69098> for more information
+   = help: add `#![feature(target_feature_11)]` to the crate attributes to enable
 
 error: aborting due to 14 previous errors
 
+For more information about this error, try `rustc --explain E0658`.