Bootstrap tests failed with local stage0 cargo and rustc
Backported changes from https://github.com/rust-lang/rust/pull/51977

From 0834d9d771e912f51deca6c25699e44734624546 Mon Sep 17 00:00:00 2001
From: Nikolai Merinov <nikolai.merinov@member.fsf.org>
Date: Mon, 2 Jul 2018 01:45:35 +0500
Subject: [PATCH] bootstrap: tests should use rustc from config.toml

Tests should always use "rustc" and "cargo" from config.toml instead
of assuming that stage0 binaries was downloaded to build directory.
---
 src/bootstrap/bootstrap.py | 2 ++
 src/bootstrap/config.rs    | 6 ++----
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/bootstrap/bootstrap.py b/src/bootstrap/bootstrap.py
index 487440becf..1701f7b83a 100644
--- a/src/bootstrap/bootstrap.py
+++ b/src/bootstrap/bootstrap.py
@@ -788,6 +788,8 @@ def bootstrap(help_triggered):
     env["BOOTSTRAP_PARENT_ID"] = str(os.getpid())
     env["BOOTSTRAP_PYTHON"] = sys.executable
     env["BUILD_DIR"] = build.build_dir
+    env["CARGO"] = build.cargo()
+    env["RUSTC"] = build.rustc()
     run(args, env=env, verbose=build.verbose)
 
 
diff --git a/src/bootstrap/config.rs b/src/bootstrap/config.rs
index 6dd6291be2..d1a0deb583 100644
--- a/src/bootstrap/config.rs
+++ b/src/bootstrap/config.rs
@@ -23,7 +23,6 @@ use std::cmp;
 
 use num_cpus;
 use toml;
-use util::exe;
 use cache::{INTERNER, Interned};
 use flags::Flags;
 pub use flags::Subcommand;
@@ -362,9 +361,8 @@ impl Config {
         config.src = Config::path_from_python("SRC");
         config.out = Config::path_from_python("BUILD_DIR");
 
-        let stage0_root = config.out.join(&config.build).join("stage0/bin");
-        config.initial_rustc = stage0_root.join(exe("rustc", &config.build));
-        config.initial_cargo = stage0_root.join(exe("cargo", &config.build));
+        config.initial_rustc = Config::path_from_python("RUSTC");
+        config.initial_cargo = Config::path_from_python("CARGO");
 
         config
     }
-- 
2.17.1

43e4fa1'>root</a>/<a href='/guix/log/AUTHORS?id=9470f901d93b7163fb4d146046b456c9343e4fa1'>AUTHORS</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/AUTHORS?id=9470f901d93b7163fb4d146046b456c9343e4fa1&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
v class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/system/uuid.scm?id=7c840b206383cae324da8c2fd593786f43642fc5&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2024-09-01 02:00:00 +0200'>2024-09-01</span></td><td><a href='/guix/commit/gnu/system/uuid.scm?id=876c343bbfe043dfc1b04cecaeed1e374843f4ed'>uuid: Add support for exFAT.</a><span class='msg-avail'>...<span class='msg-tooltip'>We expect users to use the generic STRING-&gt;FAT-UUID procedure.
This is consistent with how we already treat FAT32 vs FAT16.
It is not consistent with how we export 8 different aliases for
STRING-&gt;DCE-UUID, but I'm unconvinced that would be better.

* gnu/system/uuid.scm (%uuid-parsers, %uuid-printers):
Add the ‘exfat’ file system type.

Change-Id: Ia31482716e4395f9f10f794f49fb31c9f330a2e3
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2023-06-18 02:00:10 +0200'>2023-06-18</span></td><td><a href='/guix/commit/gnu/system/uuid.scm?id=65ed7a61f1ad01da440f0e7e08bfc32b43deed73'>uuid: Fix NTFS UUID stringification.</a><span class='msg-avail'>...<span class='msg-tooltip'>Previously, (ntfs-uuid-&gt;string (string-&gt;ntfs-uuid"5234ED0D34ECF53F"))
would yield "5234EDD34ECF53F".

Reported by sughosha in #guix.

* gnu/system/uuid.scm (ntfs-uuid-&gt;string): Pad hex bytes with zero when
needed.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2021-09-23 18:17:17 +0200'>2021-09-23</span></td><td><a href='/guix/commit/gnu/system/uuid.scm?id=90604348e14913da48327da05113d7da8ae7655a'>uuid: Support XFS.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/system/uuid.scm (string-&gt;xfs-uuid): New procedure.
(%uuid-parsers, %uuid-printers): Add ‘xfs’ file system type.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>