Don't fail to remove files if they are missing

compiler/rustc_codegen_llvm/src/back/write.rs

@@ -11,6 +11,7 @@ use crate::llvm_util;
 use crate::type_::Type;
 use crate::LlvmCodegenBackend;
 use crate::ModuleLlvm;
+use rustc_codegen_ssa::back::link::ensure_removed;
 use rustc_codegen_ssa::back::write::{
     BitcodeSection, CodegenContext, EmitObj, ModuleConfig, TargetMachineFactoryConfig,
     TargetMachineFactoryFn,
@@ -879,9 +880,7 @@ pub(crate) unsafe fn codegen(
 
                 if !config.emit_bc {
                     debug!("removing_bitcode {:?}", bc_out);
-                    if let Err(e) = fs::remove_file(&bc_out) {
-                        diag_handler.err(&format!("failed to remove bitcode: {}", e));
-                    }
+                    ensure_removed(diag_handler, &bc_out);
                 }
             }
 

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -1,5 +1,6 @@
 use rustc_data_structures::fx::FxHashSet;
 use rustc_data_structures::temp_dir::MaybeTempDir;
+use rustc_errors::Handler;
 use rustc_fs_util::fix_windows_verbatim_for_gcc;
 use rustc_hir::def_id::CrateNum;
 use rustc_middle::middle::cstore::{EncodedMetadata, LibSource};
@@ -34,9 +35,11 @@ use std::path::{Path, PathBuf};
 use std::process::{ExitStatus, Output, Stdio};
 use std::{ascii, char, env, fmt, fs, io, mem, str};
 
-pub fn remove(sess: &Session, path: &Path) {
+pub fn ensure_removed(diag_handler: &Handler, path: &Path) {
     if let Err(e) = fs::remove_file(path) {
-        sess.err(&format!("failed to remove {}: {}", path.display(), e));
+        if e.kind() != io::ErrorKind::NotFound {
+            diag_handler.err(&format!("failed to remove {}: {}", path.display(), e));
+        }
     }
 }
 
@@ -112,11 +115,11 @@ pub fn link_binary<'a, B: ArchiveBuilder<'a>>(
         if !sess.opts.cg.save_temps {
             let remove_temps_from_module = |module: &CompiledModule| {
                 if let Some(ref obj) = module.object {
-                    remove(sess, obj);
+                    ensure_removed(sess.diagnostic(), obj);
                 }
 
                 if let Some(ref obj) = module.dwarf_object {
-                    remove(sess, obj);
+                    ensure_removed(sess.diagnostic(), obj);
                 }
             };
 

compiler/rustc_codegen_ssa/src/back/write.rs

@@ -1,4 +1,4 @@
-use super::link::{self, remove};
+use super::link::{self, ensure_removed};
 use super::linker::LinkerInfo;
 use super::lto::{self, SerializedModule};
 use super::symbol_export::symbol_name_for_instance_in_crate;
@@ -543,7 +543,7 @@ fn produce_final_output_artifacts(
             copy_gracefully(&path, &crate_output.path(output_type));
             if !sess.opts.cg.save_temps && !keep_numbered {
                 // The user just wants `foo.x`, not `foo.#module-name#.x`.
-                remove(sess, &path);
+                ensure_removed(sess.diagnostic(), &path);
             }
         } else {
             let ext = crate_output
@@ -642,33 +642,33 @@ fn produce_final_output_artifacts(
         for module in compiled_modules.modules.iter() {
             if let Some(ref path) = module.object {
                 if !keep_numbered_objects {
-                    remove(sess, path);
+                    ensure_removed(sess.diagnostic(), path);
                 }
             }
 
             if let Some(ref path) = module.dwarf_object {
                 if !keep_numbered_objects {
-                    remove(sess, path);
+                    ensure_removed(sess.diagnostic(), path);
                 }
             }
 
             if let Some(ref path) = module.bytecode {
                 if !keep_numbered_bitcode {
-                    remove(sess, path);
+                    ensure_removed(sess.diagnostic(), path);
                 }
             }
         }
 
         if !user_wants_bitcode {
             if let Some(ref metadata_module) = compiled_modules.metadata_module {
                 if let Some(ref path) = metadata_module.bytecode {
-                    remove(sess, &path);
+                    ensure_removed(sess.diagnostic(), &path);
                 }
             }
 
             if let Some(ref allocator_module) = compiled_modules.allocator_module {
                 if let Some(ref path) = allocator_module.bytecode {
-                    remove(sess, path);
+                    ensure_removed(sess.diagnostic(), path);
                 }
             }
         }

src/test/ui/debuginfo-emit-llvm-ir-and-split-debuginfo.rs

@@ -0,0 +1,7 @@
+// build-pass
+//
+// compile-flags: -g --emit=llvm-ir -Zunstable-options -Csplit-debuginfo=unpacked
+//
+// Make sure that we don't explode with an error if we don't actually end up emitting any `dwo`s,
+// as would be the case if we don't actually codegen anything.
+#![crate_type="rlib"]