Unrolled build for rust-lang#124501

Rollup merge of rust-lang#124501 - VladimirMakaev:add-lldb-to-config-toml, r=Mark-Simulacrum

add support to override lldb binary path for ./x test

When running debuginfo tests I couldn't set custom build of lldb. The `src/bootstrap/src/core/build_steps/test.rs` has "lldb" hardcoded. I ended up hacking `src/bootstrap/src/core/build_steps/test.rs` just to get the tests running the way I wanted.

Then I've found out that we can override `gdb` under [build] section. This PR enables the same for `lldb`

config.example.toml

@@ -254,6 +254,10 @@
 # executing the debuginfo test suite.
 #gdb = "gdb"
 
+# The path to (or name of) the LLDB executable to use. This is only used for
+# executing the debuginfo test suite.
+#lldb = "lldb"
+
 # The node.js executable to use. Note that this is only used for the emscripten
 # target when running tests, otherwise this can be omitted.
 #nodejs = "node"

src/bootstrap/src/core/build_steps/test.rs

@@ -1892,15 +1892,16 @@ NOTE: if you're sure you want to do this, please open an issue as to why. In the
                     .to_string()
             })
         };
-        let lldb_exe = "lldb";
-        let lldb_version = Command::new(lldb_exe)
+
+        let lldb_exe = builder.config.lldb.clone().unwrap_or_else(|| PathBuf::from("lldb"));
+        let lldb_version = Command::new(&lldb_exe)
             .arg("--version")
             .output()
             .map(|output| String::from_utf8_lossy(&output.stdout).to_string())
             .ok();
         if let Some(ref vers) = lldb_version {
             cmd.arg("--lldb-version").arg(vers);
-            let lldb_python_dir = run(Command::new(lldb_exe).arg("-P")).ok();
+            let lldb_python_dir = run(Command::new(&lldb_exe).arg("-P")).ok();
             if let Some(ref dir) = lldb_python_dir {
                 cmd.arg("--lldb-python-dir").arg(dir);
             }

src/bootstrap/src/core/config/config.rs

@@ -329,6 +329,7 @@ pub struct Config {
     pub nodejs: Option<PathBuf>,
     pub npm: Option<PathBuf>,
     pub gdb: Option<PathBuf>,
+    pub lldb: Option<PathBuf>,
     pub python: Option<PathBuf>,
     pub reuse: Option<PathBuf>,
     pub cargo_native_static: bool,
@@ -834,6 +835,7 @@ define_config! {
         docs_minification: Option<bool> = "docs-minification",
         submodules: Option<bool> = "submodules",
         gdb: Option<String> = "gdb",
+        lldb: Option<String> = "lldb",
         nodejs: Option<String> = "nodejs",
         npm: Option<String> = "npm",
         python: Option<String> = "python",
@@ -1410,6 +1412,7 @@ impl Config {
             docs_minification,
             submodules,
             gdb,
+            lldb,
             nodejs,
             npm,
             python,
@@ -1502,6 +1505,7 @@ impl Config {
         config.nodejs = nodejs.map(PathBuf::from);
         config.npm = npm.map(PathBuf::from);
         config.gdb = gdb.map(PathBuf::from);
+        config.lldb = lldb.map(PathBuf::from);
         config.python = python.map(PathBuf::from);
         config.reuse = reuse.map(PathBuf::from);
         config.submodules = submodules;

src/bootstrap/src/utils/change_tracker.rs

@@ -175,4 +175,9 @@ pub const CONFIG_CHANGE_HISTORY: &[ChangeInfo] = &[
         severity: ChangeSeverity::Warning,
         summary: "The deprecated field `changelog-seen` has been removed. Using that field in `config.toml` from now on will result in breakage.",
     },
+    ChangeInfo {
+        change_id: 124501,
+        severity: ChangeSeverity::Info,
+        summary: "New option `build.lldb` that will override the default lldb binary path used in debuginfo tests",
+    },
 ];