Fix some linking of LLVM's dynamic library

Ensure it shows up in the same places it did before so tools can find it
at runtime.

src/bootstrap/compile.rs

@@ -579,24 +579,6 @@ impl Step for RustcLink {
     }
 }
 
-fn copy_lld_to_sysroot(builder: &Builder<'_>,
-                       target_compiler: Compiler,
-                       lld_install_root: &Path) {
-    let target = target_compiler.host;
-
-    let dst = builder.sysroot_libdir(target_compiler, target)
-        .parent()
-        .unwrap()
-        .join("bin");
-    t!(fs::create_dir_all(&dst));
-
-    let src_exe = exe("lld", &target);
-    let dst_exe = exe("rust-lld", &target);
-    // we prepend this bin directory to the user PATH when linking Rust binaries. To
-    // avoid shadowing the system LLD we rename the LLD we provide to `rust-lld`.
-    builder.copy(&lld_install_root.join("bin").join(&src_exe), &dst.join(&dst_exe));
-}
-
 /// Cargo's output path for the standard library in a given stage, compiled
 /// by a particular compiler for the specified target.
 pub fn libstd_stamp(
@@ -745,10 +727,16 @@ impl Step for Assemble {
             }
         }
 
+        let libdir = builder.sysroot_libdir(target_compiler, target_compiler.host);
         if let Some(lld_install) = lld_install {
-            copy_lld_to_sysroot(builder, target_compiler, &lld_install);
+            let src_exe = exe("lld", &target_compiler.host);
+            let dst_exe = exe("rust-lld", &target_compiler.host);
+            // we prepend this bin directory to the user PATH when linking Rust binaries. To
+            // avoid shadowing the system LLD we rename the LLD we provide to `rust-lld`.
+            let dst = libdir.parent().unwrap().join("bin");
+            t!(fs::create_dir_all(&dst));
+            builder.copy(&lld_install.join("bin").join(&src_exe), &dst.join(&dst_exe));
         }
-
         dist::maybe_install_llvm_dylib(builder, target_compiler.host, &sysroot);
 
         // Link the compiler binary itself into place

src/bootstrap/dist.rs

@@ -2124,6 +2124,10 @@ impl Step for HashSign {
 
 // Maybe add libLLVM.so to the lib-dir. It will only have been built if
 // LLVM tools are linked dynamically.
+//
+// We add this to both the libdir of the rustc binary itself (for it to load at
+// runtime) and also to the target directory so it can find it at link-time.
+//
 // Note: This function does no yet support Windows but we also don't support
 //       linking LLVM tools dynamically on Windows yet.
 pub fn maybe_install_llvm_dylib(builder: &Builder<'_>,
@@ -2132,13 +2136,19 @@ pub fn maybe_install_llvm_dylib(builder: &Builder<'_>,
     let src_libdir = builder
         .llvm_out(target)
         .join("lib");
-    let dst_libdir = sysroot.join("lib/rustlib").join(&*target).join("lib");
-    t!(fs::create_dir_all(&dst_libdir));
+    let dst_libdir1 = sysroot.join("lib/rustlib").join(&*target).join("lib");
+    let dst_libdir2 = sysroot.join(builder.sysroot_libdir_relative(Compiler {
+        stage: 1,
+        host: target,
+    }));
+    t!(fs::create_dir_all(&dst_libdir1));
+    t!(fs::create_dir_all(&dst_libdir2));
 
     if target.contains("apple-darwin") {
         let llvm_dylib_path = src_libdir.join("libLLVM.dylib");
         if llvm_dylib_path.exists() {
-            builder.install(&llvm_dylib_path, &dst_libdir, 0o644);
+            builder.install(&llvm_dylib_path, &dst_libdir1, 0o644);
+            builder.install(&llvm_dylib_path, &dst_libdir2, 0o644);
         }
         return
     }
@@ -2154,7 +2164,8 @@ pub fn maybe_install_llvm_dylib(builder: &Builder<'_>,
         });
 
 
-        builder.install(&llvm_dylib_path, &dst_libdir, 0o644);
+        builder.install(&llvm_dylib_path, &dst_libdir1, 0o644);
+        builder.install(&llvm_dylib_path, &dst_libdir2, 0o644);
     }
 }
 

src/bootstrap/doc.rs

@@ -433,7 +433,7 @@ impl Step for Std {
         builder.info(&format!("Documenting stage{} std ({})", stage, target));
         let out = builder.doc_out(target);
         t!(fs::create_dir_all(&out));
-        let compiler = builder.compiler_for(stage, builder.config.build, target);
+        let compiler = builder.compiler(stage, builder.config.build);
 
         builder.ensure(compile::Std { compiler, target });
         let out_dir = builder.stage_out(compiler, Mode::Std)