diff --git a/compiler/rustc_codegen_ssa/src/mir/mod.rs b/compiler/rustc_codegen_ssa/src/mir/mod.rs index 387a5366b209b..dc589a5fd306e 100644 --- a/compiler/rustc_codegen_ssa/src/mir/mod.rs +++ b/compiler/rustc_codegen_ssa/src/mir/mod.rs @@ -2,6 +2,7 @@ use crate::base; use crate::traits::*; use rustc_index::bit_set::BitSet; use rustc_index::IndexVec; +use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags; use rustc_middle::mir; use rustc_middle::mir::traversal; use rustc_middle::mir::UnwindTerminateReason; @@ -290,6 +291,12 @@ fn arg_local_refs<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( let mut num_untupled = None; + let codegen_fn_attrs = bx.tcx().codegen_fn_attrs(fx.instance.def_id()); + let naked = codegen_fn_attrs.flags.contains(CodegenFnAttrFlags::NAKED); + if naked { + return vec![]; + } + let args = mir .args_iter() .enumerate() diff --git a/tests/codegen/cffi/c-variadic-naked.rs b/tests/codegen/cffi/c-variadic-naked.rs new file mode 100644 index 0000000000000..807873ea3689f --- /dev/null +++ b/tests/codegen/cffi/c-variadic-naked.rs @@ -0,0 +1,19 @@ +//@ needs-asm-support +//@ only-x86_64 + +// tests that `va_start` is not injected into naked functions + +#![crate_type = "lib"] +#![feature(c_variadic)] +#![feature(naked_functions)] +#![no_std] + +#[naked] +pub unsafe extern "C" fn c_variadic(_: usize, _: ...) { + // CHECK-NOT: va_start + // CHECK-NOT: alloca + core::arch::asm! { + "ret", + options(noreturn), + } +} diff --git a/tests/codegen/naked-fn/naked-functions.rs b/tests/codegen/naked-fn/naked-functions.rs index 755dd15511269..3c426825537b6 100644 --- a/tests/codegen/naked-fn/naked-functions.rs +++ b/tests/codegen/naked-fn/naked-functions.rs @@ -19,7 +19,7 @@ pub unsafe extern "C" fn naked_empty() { } // CHECK: Function Attrs: naked -// CHECK-NEXT: define{{.*}}i{{[0-9]+}} @naked_with_args_and_return(i64 %a, i64 %b) +// CHECK-NEXT: define{{.*}}i{{[0-9]+}} @naked_with_args_and_return(i64 %0, i64 %1) #[no_mangle] #[naked] pub unsafe extern "C" fn naked_with_args_and_return(a: isize, b: isize) -> isize {