use Instance::expect_resolve() instead of unwraping Instance::resolve()

Author: RalfJung

compiler/rustc_codegen_cranelift/src/main_shim.rs

@@ -115,14 +115,12 @@ pub(crate) fn maybe_create_entry_wrapper(
                         termination_trait,
                     )
                     .unwrap();
-                let report = Instance::resolve(
+                let report = Instance::expect_resolve(
                     tcx,
                     ParamEnv::reveal_all(),
                     report.def_id,
                     tcx.mk_args(&[GenericArg::from(main_ret_ty)]),
                 )
-                .unwrap()
-                .unwrap()
                 .polymorphize(tcx);
 
                 let report_name = tcx.symbol_name(report).name;
@@ -142,14 +140,12 @@ pub(crate) fn maybe_create_entry_wrapper(
                 }
             } else if is_main_fn {
                 let start_def_id = tcx.require_lang_item(LangItem::Start, None);
-                let start_instance = Instance::resolve(
+                let start_instance = Instance::expect_resolve(
                     tcx,
                     ParamEnv::reveal_all(),
                     start_def_id,
                     tcx.mk_args(&[main_ret_ty.into()]),
                 )
-                .unwrap()
-                .unwrap()
                 .polymorphize(tcx);
                 let start_func_id = import_function(tcx, m, start_instance);
 

compiler/rustc_codegen_gcc/src/context.rs

@@ -473,14 +473,12 @@ impl<'gcc, 'tcx> MiscMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
         let tcx = self.tcx;
         let func = match tcx.lang_items().eh_personality() {
             Some(def_id) if !wants_msvc_seh(self.sess()) => {
-                let instance = ty::Instance::resolve(
+                let instance = ty::Instance::expect_resolve(
                     tcx,
                     ty::ParamEnv::reveal_all(),
                     def_id,
                     ty::List::empty(),
-                )
-                .unwrap()
-                .unwrap();
+                );
 
                 let symbol_name = tcx.symbol_name(instance).name;
                 let fn_abi = self.fn_abi_of_instance(instance, ty::List::empty());

compiler/rustc_codegen_llvm/src/context.rs

@@ -558,11 +558,12 @@ impl<'ll, 'tcx> MiscMethods<'tcx> for CodegenCx<'ll, 'tcx> {
 
         let tcx = self.tcx;
         let llfn = match tcx.lang_items().eh_personality() {
-            Some(def_id) if name.is_none() => self.get_fn_addr(
-                ty::Instance::resolve(tcx, ty::ParamEnv::reveal_all(), def_id, ty::List::empty())
-                    .unwrap()
-                    .unwrap(),
-            ),
+            Some(def_id) if name.is_none() => self.get_fn_addr(ty::Instance::expect_resolve(
+                tcx,
+                ty::ParamEnv::reveal_all(),
+                def_id,
+                ty::List::empty(),
+            )),
             _ => {
                 let name = name.unwrap_or("rust_eh_personality");
                 if let Some(llfn) = self.get_declared_value(name) {

compiler/rustc_codegen_ssa/src/base.rs

@@ -467,16 +467,12 @@ pub fn maybe_create_entry_wrapper<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
 
         let (start_fn, start_ty, args) = if let EntryFnType::Main { sigpipe } = entry_type {
             let start_def_id = cx.tcx().require_lang_item(LangItem::Start, None);
-            let start_fn = cx.get_fn_addr(
-                ty::Instance::resolve(
-                    cx.tcx(),
-                    ty::ParamEnv::reveal_all(),
-                    start_def_id,
-                    cx.tcx().mk_args(&[main_ret_ty.into()]),
-                )
-                .unwrap()
-                .unwrap(),
-            );
+            let start_fn = cx.get_fn_addr(ty::Instance::expect_resolve(
+                cx.tcx(),
+                ty::ParamEnv::reveal_all(),
+                start_def_id,
+                cx.tcx().mk_args(&[main_ret_ty.into()]),
+            ));
 
             let i8_ty = cx.type_i8();
             let arg_sigpipe = bx.const_u8(sigpipe);

compiler/rustc_const_eval/src/const_eval/machine.rs

@@ -243,14 +243,12 @@ impl<'mir, 'tcx: 'mir> CompileTimeEvalContext<'mir, 'tcx> {
         } else if Some(def_id) == self.tcx.lang_items().panic_fmt() {
             // For panic_fmt, call const_panic_fmt instead.
             let const_def_id = self.tcx.require_lang_item(LangItem::ConstPanicFmt, None);
-            let new_instance = ty::Instance::resolve(
+            let new_instance = ty::Instance::expect_resolve(
                 *self.tcx,
                 ty::ParamEnv::reveal_all(),
                 const_def_id,
                 instance.args,
-            )
-            .unwrap()
-            .unwrap();
+            );
 
             return Ok(Some(new_instance));
         } else if Some(def_id) == self.tcx.lang_items().align_offset_fn() {

compiler/rustc_monomorphize/src/collector.rs

@@ -1339,14 +1339,12 @@ impl<'v> RootCollector<'_, 'v> {
             main_ret_ty.no_bound_vars().unwrap(),
         );
 
-        let start_instance = Instance::resolve(
+        let start_instance = Instance::expect_resolve(
             self.tcx,
             ty::ParamEnv::reveal_all(),
             start_def_id,
             self.tcx.mk_args(&[main_ret_ty.into()]),
-        )
-        .unwrap()
-        .unwrap();
+        );
 
         self.output.push(create_fn_mono_item(self.tcx, start_instance, DUMMY_SP));
     }