remove unused return types such as empty Results or Options that would always be Some(..)

remove unused return type of dropck::check_drop_obligations()
don't wrap return type in Option in get_macro_by_def_id() since we would always return Some(..)
remove redundant return type of back::write::optimize()
don't Option-wrap return type of compute_type_parameters() since we always return Some(..)
don't return empty Result in assemble_generator_candidates()
don't return empty Result in assemble_closure_candidates()
don't return empty result in assemble_fn_pointer_candidates()
don't return empty result in assemble_candidates_from_impls()
don't return empty result in assemble_candidates_from_auto_impls()
don't return emtpy result in assemble_candidates_for_trait_alias()
don't return empty result in assemble_builtin_bound_candidates()
don't return empty results in assemble_extension_candidates_for_traits_in_scope() and assemble_extension_candidates_for_trait()
remove redundant wrapping of return type of StripItem::strip() since it always returns Some(..)
remove unused return type of assemble_extension_candidates_for_all_traits()

1 files changed, 2 insertions, 3 deletions

diff --git a/compiler/rustc_codegen_llvm/src/back/write.rs b/compiler/rustc_codegen_llvm/src/back/write.rs
index 3fda1e26dae..230e11f274e 100644
--- a/compiler/rustc_codegen_llvm/src/back/write.rs
+++ b/compiler/rustc_codegen_llvm/src/back/write.rs
@@ -485,7 +485,7 @@ pub(crate) unsafe fn optimize(
     diag_handler: &Handler,
     module: &ModuleCodegen<ModuleLlvm>,
     config: &ModuleConfig,
-) -> Result<(), FatalError> {
+) {
     let _timer = cgcx.prof.generic_activity_with_arg("LLVM_module_optimize", &module.name[..]);
 
     let llmod = module.module_llvm.llmod();
@@ -511,7 +511,7 @@ pub(crate) unsafe fn optimize(
                 _ => llvm::OptStage::PreLinkNoLTO,
             };
             optimize_with_new_llvm_pass_manager(cgcx, module, config, opt_level, opt_stage);
-            return Ok(());
+            return;
         }
 
         if cgcx.prof.llvm_recording_enabled() {
@@ -634,7 +634,6 @@ pub(crate) unsafe fn optimize(
         llvm::LLVMDisposePassManager(fpm);
         llvm::LLVMDisposePassManager(mpm);
     }
-    Ok(())
 }
 
 unsafe fn add_sanitizer_passes(config: &ModuleConfig, passes: &mut Vec<&'static mut llvm::Pass>) {