fix: reorder --remap-path-prefix flags for -Zbuild-std

Order of `--remap-path-prefix` flags is important for `-Zbuild-std`.
We want to show `/rustc/<hash>/library/std` instead of `std-0.0.0`.

Author: weihanglo

src/cargo/core/compiler/mod.rs

@@ -1214,8 +1214,6 @@ fn trim_paths_args(
         }
         remap
     };
-    cmd.arg(sysroot_remap);
-
     let package_remap = {
         let pkg_root = unit.pkg.root();
         let ws_root = cx.bcx.ws.root();
@@ -1242,7 +1240,11 @@ fn trim_paths_args(
         }
         remap
     };
+
+    // Order of `--remap-path-prefix` flags is important for `-Zbuild-std`.
+    // We want to show `/rustc/<hash>/library/std` instead of `std-0.0.0`.
     cmd.arg(package_remap);
+    cmd.arg(sysroot_remap);
 
     Ok(())
 }

tests/build-std/main.rs

@@ -267,8 +267,8 @@ fn remap_path_scope() {
 [..]thread '[..]' panicked at [..]src/main.rs:3:[..]",
         )
         .with_stderr_contains("remap to /rustc/<hash>")
-        .with_stderr_contains("[..]at std-0.0.0/src/[..]")
+        .with_stderr_contains("[..]at /rustc/[..]/library/std/src/[..]")
         .with_stderr_contains("[..]at src/main.rs:3[..]")
-        .with_stderr_contains("[..]at core-0.0.0/src/[..]")
+        .with_stderr_contains("[..]at /rustc/[..]/library/core/src/[..]")
         .run();
 }