Rollup merge of #71205 - NeoRaider:check_attr, r=jonas-schievink

rustc: fix check_attr() for methods, closures and foreign functions

This fixes an issue that previously turned up for methods in https://github.com/rust-lang/rust/pull/69274, but also exists for closures and foreign function: `check_attr` does not call `codegen_fn_attrs()` for these types when it should, meaning that incorrectly used function attributes are not diagnosed without codegen.

The issue affects our UI tests, as they run with `--emit=metadata` by default, but as it turns out, this is not the only case: Function attributes are not checked on any dead code without this fix!

This makes the fix a **breaking change**. The following very silly Rust programs compiles fine on stable Rust when it should not, which is fixed by this PR.
```rust
fn main() {
    #[target_feature(enable = "sse2")]
    || {};
}
```

I assume any real-world program which may trigger this issue would at least emit a dead code warning, but of course that is no guarantee that such code does not exist...

Fixes #70307

2 files changed, 13 insertions, 4 deletions

diff --git a/src/test/ui/issues/issue-3214.rs b/src/test/ui/issues/issue-3214.rs
index 9a727aa3057..030677c879f 100644
--- a/src/test/ui/issues/issue-3214.rs
+++ b/src/test/ui/issues/issue-3214.rs
@@ -1,3 +1,5 @@
+// ignore-tidy-linelength
+
 fn foo<T>() {
     struct Foo {
         x: T, //~ ERROR can't use generic parameters from outer function
@@ -5,6 +7,7 @@ fn foo<T>() {
 
     impl<T> Drop for Foo<T> {
         //~^ ERROR wrong number of type arguments
+        //~| ERROR the type parameter `T` is not constrained by the impl trait, self type, or predicates
         fn drop(&mut self) {}
     }
 }
diff --git a/src/test/ui/issues/issue-3214.stderr b/src/test/ui/issues/issue-3214.stderr
index 02c8da10bb4..30bc6cb115f 100644
--- a/src/test/ui/issues/issue-3214.stderr
+++ b/src/test/ui/issues/issue-3214.stderr
@@ -1,5 +1,5 @@
 error[E0401]: can't use generic parameters from outer function
-  --> $DIR/issue-3214.rs:3:12
+  --> $DIR/issue-3214.rs:5:12
    |
 LL | fn foo<T>() {
    |    --- - type parameter from outer function
@@ -10,12 +10,18 @@ LL |         x: T,
    |            ^ use of generic parameter from outer function
 
 error[E0107]: wrong number of type arguments: expected 0, found 1
-  --> $DIR/issue-3214.rs:6:26
+  --> $DIR/issue-3214.rs:8:26
    |
 LL |     impl<T> Drop for Foo<T> {
    |                          ^ unexpected type argument
 
-error: aborting due to 2 previous errors
+error[E0207]: the type parameter `T` is not constrained by the impl trait, self type, or predicates
+  --> $DIR/issue-3214.rs:8:10
+   |
+LL |     impl<T> Drop for Foo<T> {
+   |          ^ unconstrained type parameter
+
+error: aborting due to 3 previous errors
 
-Some errors have detailed explanations: E0107, E0401.
+Some errors have detailed explanations: E0107, E0207, E0401.
 For more information about an error, try `rustc --explain E0107`.