allow #[target_feature] on #[naked] functions

compiler/rustc_error_codes/src/error_codes/E0736.md

@@ -5,7 +5,6 @@ Notable attributes that are incompatible with `#[naked]` are:
 
 * `#[inline]`
 * `#[track_caller]`
-* `#[target_feature]`
 * `#[test]`, `#[ignore]`, `#[should_panic]`
 
 Erroneous code example:

compiler/rustc_passes/src/check_attr.rs

@@ -423,7 +423,6 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
         //
         // * `#[inline]`
         // * `#[track_caller]`
-        // * `#[target_feature]`
         // * `#[test]`, `#[ignore]`, `#[should_panic]`
         //
         // NOTE: when making changes to this list, check that `error_codes/E0736.md` remains accurate
@@ -452,6 +451,7 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
             sym::instruction_set,
             // code generation
             sym::cold,
+            sym::target_feature,
             // documentation
             sym::doc,
         ];

tests/ui/asm/naked-functions-target-feature.rs

@@ -1,13 +0,0 @@
-//@ only-x86_64
-//@ needs-asm-support
-#![feature(naked_functions)]
-#![crate_type = "lib"]
-
-use std::arch::asm;
-
-#[target_feature(enable = "sse2")]
-//~^ ERROR [E0736]
-#[naked]
-pub unsafe extern "C" fn naked_target_feature() {
-    asm!("", options(noreturn));
-}

tests/ui/asm/naked-functions-target-feature.stderr

@@ -1,12 +0,0 @@
-error[E0736]: attribute incompatible with `#[naked]`
-  --> $DIR/naked-functions-target-feature.rs:8:1
-   |
-LL | #[target_feature(enable = "sse2")]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the `target_feature` attribute is incompatible with `#[naked]`
-LL |
-LL | #[naked]
-   | -------- function marked with `#[naked]` here
-
-error: aborting due to 1 previous error
-
-For more information about this error, try `rustc --explain E0736`.

tests/ui/asm/naked-functions.rs

@@ -231,6 +231,12 @@ pub unsafe extern "C" fn compatible_codegen_attributes() {
     asm!("", options(noreturn, att_syntax));
 }
 
+#[target_feature(enable = "sse2")]
+#[naked]
+pub unsafe extern "C" fn compatible_target_feature() {
+    asm!("", options(noreturn));
+}
+
 #[doc = "foo bar baz"]
 #[naked]
 pub unsafe extern "C" fn compatible_doc_attributes() {