Auto merge of #81355 - jonas-schievink:rollup-vpaadij, r=jonas-schievink

Rollup of 14 pull requests

Successful merges:

 - #75180 (Implement Error for &(impl Error))
 - #78578 (Permit mutable references in all const contexts)
 - #79174 (Make std::future a re-export of core::future)
 - #79884 (Replace magic numbers with existing constants)
 - #80855 (Expand assert!(expr, args..) to include $crate for hygiene on 2021.)
 - #80933 (Fix sysroot option not being honored across rustc)
 - #81259 (Replace version_check dependency with own version parsing code)
 - #81264 (Add unstable option to control doctest run directory)
 - #81279 (Small refactor in typeck)
 - #81297 (Don't provide backend_optimization_level query for extern crates)
 - #81302 (Fix rendering of stabilization version for trait implementors)
 - #81310 (Do not mark unit variants as used when in path pattern)
 - #81320 (Make bad shlex parsing a pretty error)
 - #81338 (Clean up `dominators_given_rpo`)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

3 files changed, 23 insertions, 10 deletions

diff --git a/compiler/rustc_codegen_ssa/src/back/link.rs b/compiler/rustc_codegen_ssa/src/back/link.rs
index e51904f308d..72e049b6d74 100644
--- a/compiler/rustc_codegen_ssa/src/back/link.rs
+++ b/compiler/rustc_codegen_ssa/src/back/link.rs
@@ -885,9 +885,22 @@ fn link_sanitizers(sess: &Session, crate_type: CrateType, linker: &mut dyn Linke
 }
 
 fn link_sanitizer_runtime(sess: &Session, linker: &mut dyn Linker, name: &str) {
-    let default_sysroot = filesearch::get_or_default_sysroot();
-    let default_tlib =
-        filesearch::make_target_lib_path(&default_sysroot, sess.opts.target_triple.triple());
+    fn find_sanitizer_runtime(sess: &Session, filename: &String) -> PathBuf {
+        let session_tlib =
+            filesearch::make_target_lib_path(&sess.sysroot, sess.opts.target_triple.triple());
+        let path = session_tlib.join(&filename);
+        if path.exists() {
+            return session_tlib;
+        } else {
+            let default_sysroot = filesearch::get_or_default_sysroot();
+            let default_tlib = filesearch::make_target_lib_path(
+                &default_sysroot,
+                sess.opts.target_triple.triple(),
+            );
+            return default_tlib;
+        }
+    }
+
     let channel = option_env!("CFG_RELEASE_CHANNEL")
         .map(|channel| format!("-{}", channel))
         .unwrap_or_default();
@@ -898,10 +911,11 @@ fn link_sanitizer_runtime(sess: &Session, linker: &mut dyn Linker, name: &str) {
             // LLVM will link to `@rpath/*.dylib`, so we need to specify an
             // rpath to the library as well (the rpath should be absolute, see
             // PR #41352 for details).
-            let libname = format!("rustc{}_rt.{}", channel, name);
-            let rpath = default_tlib.to_str().expect("non-utf8 component in path");
+            let filename = format!("rustc{}_rt.{}", channel, name);
+            let path = find_sanitizer_runtime(&sess, &filename);
+            let rpath = path.to_str().expect("non-utf8 component in path");
             linker.args(&["-Wl,-rpath", "-Xlinker", rpath]);
-            linker.link_dylib(Symbol::intern(&libname));
+            linker.link_dylib(Symbol::intern(&filename));
         }
         "aarch64-fuchsia"
         | "aarch64-unknown-linux-gnu"
@@ -909,7 +923,7 @@ fn link_sanitizer_runtime(sess: &Session, linker: &mut dyn Linker, name: &str) {
         | "x86_64-unknown-freebsd"
         | "x86_64-unknown-linux-gnu" => {
             let filename = format!("librustc{}_rt.{}.a", channel, name);
-            let path = default_tlib.join(&filename);
+            let path = find_sanitizer_runtime(&sess, &filename).join(&filename);
             linker.link_whole_rlib(&path);
         }
         _ => {}
diff --git a/compiler/rustc_codegen_ssa/src/base.rs b/compiler/rustc_codegen_ssa/src/base.rs
index 2ce5fe5ad50..b205ea9cf6c 100644
--- a/compiler/rustc_codegen_ssa/src/base.rs
+++ b/compiler/rustc_codegen_ssa/src/base.rs
@@ -783,7 +783,7 @@ impl CrateInfo {
     }
 }
 
-pub fn provide_both(providers: &mut Providers) {
+pub fn provide(providers: &mut Providers) {
     providers.backend_optimization_level = |tcx, cratenum| {
         let for_speed = match tcx.sess.opts.optimize {
             // If globally no optimisation is done, #[optimize] has no effect.
diff --git a/compiler/rustc_codegen_ssa/src/lib.rs b/compiler/rustc_codegen_ssa/src/lib.rs
index e27eac3f69b..0307117e1c8 100644
--- a/compiler/rustc_codegen_ssa/src/lib.rs
+++ b/compiler/rustc_codegen_ssa/src/lib.rs
@@ -160,13 +160,12 @@ pub struct CodegenResults {
 
 pub fn provide(providers: &mut Providers) {
     crate::back::symbol_export::provide(providers);
-    crate::base::provide_both(providers);
+    crate::base::provide(providers);
     crate::target_features::provide(providers);
 }
 
 pub fn provide_extern(providers: &mut Providers) {
     crate::back::symbol_export::provide_extern(providers);
-    crate::base::provide_both(providers);
 }
 
 /// Checks if the given filename ends with the `.rcgu.o` extension that `rustc`