Render fn defs with target_features attrs with the attribute

Author: oli-obk

compiler/rustc_middle/src/ty/print/pretty.rs

@@ -691,7 +691,14 @@ pub trait PrettyPrinter<'tcx>: Printer<'tcx> + fmt::Write {
                 if with_reduced_queries() {
                     p!(print_def_path(def_id, args));
                 } else {
-                    let sig = self.tcx().fn_sig(def_id).instantiate(self.tcx(), args);
+                    let mut sig = self.tcx().fn_sig(def_id).instantiate(self.tcx(), args);
+                    if self.tcx().codegen_fn_attrs(def_id).safe_target_features {
+                        p!("#[target_features] ");
+                        sig = sig.map_bound(|mut sig| {
+                            sig.safety = hir::Safety::Safe;
+                            sig
+                        });
+                    }
                     p!(print(sig), " {{", print_value_path(def_id, args), "}}");
                 }
             }

tests/ui/async-await/async-closures/fn-exception-target-features.stderr

@@ -1,11 +1,12 @@
-error[E0277]: the trait bound `unsafe fn() -> Pin<Box<(dyn Future<Output = ()> + 'static)>> {target_feature}: AsyncFn()` is not satisfied
+error[E0277]: the trait bound `#[target_features] fn() -> Pin<Box<(dyn Future<Output = ()> + 'static)>> {target_feature}: AsyncFn()` is not satisfied
   --> $DIR/fn-exception-target-features.rs:16:10
    |
 LL |     test(target_feature);
-   |     ---- ^^^^^^^^^^^^^^ the trait `AsyncFn()` is not implemented for fn item `unsafe fn() -> Pin<Box<(dyn Future<Output = ()> + 'static)>> {target_feature}`
+   |     ---- ^^^^^^^^^^^^^^ unsatisfied trait bound
    |     |
    |     required by a bound introduced by this call
    |
+   = help: the trait `AsyncFn()` is not implemented for fn item `#[target_features] fn() -> Pin<Box<(dyn Future<Output = ()> + 'static)>> {target_feature}`
 note: required by a bound in `test`
   --> $DIR/fn-exception-target-features.rs:13:17
    |

tests/ui/rfcs/rfc-2396-target_feature-11/fn-traits.rs

@@ -21,9 +21,9 @@ fn call_once(f: impl FnOnce()) {
 }
 
 fn main() {
-    call(foo); //~ ERROR expected a `Fn()` closure, found `unsafe fn() {foo}`
-    call_mut(foo); //~ ERROR expected a `FnMut()` closure, found `unsafe fn() {foo}`
-    call_once(foo); //~ ERROR expected a `FnOnce()` closure, found `unsafe fn() {foo}`
+    call(foo); //~ ERROR expected a `Fn()` closure, found `#[target_features] fn() {foo}`
+    call_mut(foo); //~ ERROR expected a `FnMut()` closure, found `#[target_features] fn() {foo}`
+    call_once(foo); //~ ERROR expected a `FnOnce()` closure, found `#[target_features] fn() {foo}`
 
     call(foo_unsafe);
     //~^ ERROR expected a `Fn()` closure, found `unsafe fn() {foo_unsafe}`

tests/ui/rfcs/rfc-2396-target_feature-11/fn-traits.stderr

@@ -1,50 +1,50 @@
-error[E0277]: expected a `Fn()` closure, found `unsafe fn() {foo}`
+error[E0277]: expected a `Fn()` closure, found `#[target_features] fn() {foo}`
   --> $DIR/fn-traits.rs:24:10
    |
 LL |     call(foo);
    |     ---- ^^^ call the function in a closure: `|| unsafe { /* code */ }`
    |     |
    |     required by a bound introduced by this call
    |
-   = help: the trait `Fn()` is not implemented for fn item `unsafe fn() {foo}`
+   = help: the trait `Fn()` is not implemented for fn item `#[target_features] fn() {foo}`
    = note: unsafe function cannot be called generically without an unsafe block
-   = note: wrap the `unsafe fn() {foo}` in a closure with no arguments: `|| { /* code */ }`
+   = note: wrap the `#[target_features] fn() {foo}` in a closure with no arguments: `|| { /* code */ }`
    = note: `#[target_feature]` functions do not implement the `Fn` traits
 note: required by a bound in `call`
   --> $DIR/fn-traits.rs:11:17
    |
 LL | fn call(f: impl Fn()) {
    |                 ^^^^ required by this bound in `call`
 
-error[E0277]: expected a `FnMut()` closure, found `unsafe fn() {foo}`
+error[E0277]: expected a `FnMut()` closure, found `#[target_features] fn() {foo}`
   --> $DIR/fn-traits.rs:25:14
    |
 LL |     call_mut(foo);
    |     -------- ^^^ call the function in a closure: `|| unsafe { /* code */ }`
    |     |
    |     required by a bound introduced by this call
    |
-   = help: the trait `FnMut()` is not implemented for fn item `unsafe fn() {foo}`
+   = help: the trait `FnMut()` is not implemented for fn item `#[target_features] fn() {foo}`
    = note: unsafe function cannot be called generically without an unsafe block
-   = note: wrap the `unsafe fn() {foo}` in a closure with no arguments: `|| { /* code */ }`
+   = note: wrap the `#[target_features] fn() {foo}` in a closure with no arguments: `|| { /* code */ }`
    = note: `#[target_feature]` functions do not implement the `Fn` traits
 note: required by a bound in `call_mut`
   --> $DIR/fn-traits.rs:15:25
    |
 LL | fn call_mut(mut f: impl FnMut()) {
    |                         ^^^^^^^ required by this bound in `call_mut`
 
-error[E0277]: expected a `FnOnce()` closure, found `unsafe fn() {foo}`
+error[E0277]: expected a `FnOnce()` closure, found `#[target_features] fn() {foo}`
   --> $DIR/fn-traits.rs:26:15
    |
 LL |     call_once(foo);
    |     --------- ^^^ call the function in a closure: `|| unsafe { /* code */ }`
    |     |
    |     required by a bound introduced by this call
    |
-   = help: the trait `FnOnce()` is not implemented for fn item `unsafe fn() {foo}`
+   = help: the trait `FnOnce()` is not implemented for fn item `#[target_features] fn() {foo}`
    = note: unsafe function cannot be called generically without an unsafe block
-   = note: wrap the `unsafe fn() {foo}` in a closure with no arguments: `|| { /* code */ }`
+   = note: wrap the `#[target_features] fn() {foo}` in a closure with no arguments: `|| { /* code */ }`
    = note: `#[target_feature]` functions do not implement the `Fn` traits
 note: required by a bound in `call_once`
   --> $DIR/fn-traits.rs:19:22