diff --git a/compiler/rustc_monomorphize/src/collector.rs b/compiler/rustc_monomorphize/src/collector.rs index 0ae635f9b73e5..9f449868f0316 100644 --- a/compiler/rustc_monomorphize/src/collector.rs +++ b/compiler/rustc_monomorphize/src/collector.rs @@ -888,7 +888,9 @@ fn visit_instance_use<'tcx>( if tcx.should_codegen_locally(panic_instance) { output.push(create_fn_mono_item(tcx, panic_instance, source)); } - } else if tcx.has_attr(def_id, sym::rustc_intrinsic) { + } else if tcx.has_attr(def_id, sym::rustc_intrinsic) + && !tcx.has_attr(def_id, sym::rustc_intrinsic_must_be_overridden) + { // Codegen the fallback body of intrinsics with fallback bodies let instance = ty::Instance::new(def_id, instance.args); if tcx.should_codegen_locally(instance) { diff --git a/tests/codegen/intrinsics/rustc_intrinsic_must_be_overridden.rs b/tests/codegen/intrinsics/rustc_intrinsic_must_be_overridden.rs new file mode 100644 index 0000000000000..b41e441d309da --- /dev/null +++ b/tests/codegen/intrinsics/rustc_intrinsic_must_be_overridden.rs @@ -0,0 +1,14 @@ +//@ revisions: OPT0 OPT1 +//@ [OPT0] compile-flags: -Copt-level=0 +//@ [OPT1] compile-flags: -Copt-level=1 +//@ compile-flags: -Cno-prepopulate-passes + +#![crate_type = "lib"] +#![feature(core_intrinsics)] + +// CHECK-NOT: core::intrinsics::size_of_val + +#[no_mangle] +pub unsafe fn size_of_val(ptr: *const i32) -> usize { + core::intrinsics::size_of_val(ptr) +}