From c3000ad3baf4c135abc5740c09f726a8862c2ac3 Mon Sep 17 00:00:00 2001
From: jdonszelmann <jonabent@gmail.com>
Date: Thu, 22 Aug 2024 19:48:39 +0200
Subject: [PATCH] add repr to the allowlist for naked functions, and test that
 it works

---
 compiler/rustc_passes/src/check_attr.rs |  1 +
 tests/codegen/naked-fn/aligned.rs       | 20 ++++++++++++++++++++
 2 files changed, 21 insertions(+)
 create mode 100644 tests/codegen/naked-fn/aligned.rs

diff --git a/compiler/rustc_passes/src/check_attr.rs b/compiler/rustc_passes/src/check_attr.rs
index c93fb5c23b1c4..be2b01309c59e 100644
--- a/compiler/rustc_passes/src/check_attr.rs
+++ b/compiler/rustc_passes/src/check_attr.rs
@@ -516,6 +516,7 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
             sym::no_mangle,
             sym::naked,
             sym::instruction_set,
+            sym::repr,
             // code generation
             sym::cold,
             sym::target_feature,
diff --git a/tests/codegen/naked-fn/aligned.rs b/tests/codegen/naked-fn/aligned.rs
new file mode 100644
index 0000000000000..d5faac44836fe
--- /dev/null
+++ b/tests/codegen/naked-fn/aligned.rs
@@ -0,0 +1,20 @@
+//@ compile-flags: -C no-prepopulate-passes -Copt-level=0
+//@ needs-asm-support
+//@ ignore-arm no "ret" mnemonic
+
+#![crate_type = "lib"]
+#![feature(naked_functions, fn_align)]
+use std::arch::asm;
+
+// CHECK: Function Attrs: naked
+// CHECK-NEXT: define{{.*}}void @naked_empty()
+// CHECK: align 16
+#[repr(align(16))]
+#[no_mangle]
+#[naked]
+pub unsafe extern "C" fn naked_empty() {
+    // CHECK-NEXT: start:
+    // CHECK-NEXT: call void asm
+    // CHECK-NEXT: unreachable
+    asm!("ret", options(noreturn));
+}