Don't needlessly build rustdoc for compiletest.

For most tests, rustdoc isn't needed, so avoid building it.

Author: Mark-Simulacrum

src/bootstrap/check.rs

@@ -562,7 +562,12 @@ impl Step for Compiletest {
         cmd.arg("--compile-lib-path").arg(builder.rustc_libdir(compiler));
         cmd.arg("--run-lib-path").arg(builder.sysroot_libdir(compiler, target));
         cmd.arg("--rustc-path").arg(builder.rustc(compiler));
-        cmd.arg("--rustdoc-path").arg(builder.rustdoc(compiler));
+
+        // Avoid depending on rustdoc when we don't need it.
+        if mode == "rustdoc" || mode == "run-make" {
+            cmd.arg("--rustdoc-path").arg(builder.rustdoc(compiler));
+        }
+
         cmd.arg("--src-base").arg(build.src.join("src/test").join(suite));
         cmd.arg("--build-base").arg(testdir(build, compiler.host).join(suite));
         cmd.arg("--stage-id").arg(format!("stage{}-{}", compiler.stage, target));

src/tools/compiletest/src/common.rs

@@ -93,7 +93,7 @@ pub struct Config {
     pub rustc_path: PathBuf,
 
     // The rustdoc executable
-    pub rustdoc_path: PathBuf,
+    pub rustdoc_path: Option<PathBuf>,
 
     // The python executable to use for LLDB
     pub lldb_python: String,

src/tools/compiletest/src/main.rs

@@ -67,7 +67,7 @@ pub fn parse_config(args: Vec<String> ) -> Config {
     opts.reqopt("", "compile-lib-path", "path to host shared libraries", "PATH")
         .reqopt("", "run-lib-path", "path to target shared libraries", "PATH")
         .reqopt("", "rustc-path", "path to rustc to use for compiling", "PATH")
-        .reqopt("", "rustdoc-path", "path to rustdoc to use for compiling", "PATH")
+        .optopt("", "rustdoc-path", "path to rustdoc to use for compiling", "PATH")
         .reqopt("", "lldb-python", "path to python to use for doc tests", "PATH")
         .reqopt("", "docck-python", "path to python to use for doc tests", "PATH")
         .optopt("", "valgrind-path", "path to Valgrind executable for Valgrind tests", "PROGRAM")
@@ -157,7 +157,7 @@ pub fn parse_config(args: Vec<String> ) -> Config {
         compile_lib_path: make_absolute(opt_path(matches, "compile-lib-path")),
         run_lib_path: make_absolute(opt_path(matches, "run-lib-path")),
         rustc_path: opt_path(matches, "rustc-path"),
-        rustdoc_path: opt_path(matches, "rustdoc-path"),
+        rustdoc_path: matches.opt_str("rustdoc-path").map(PathBuf::from),
         lldb_python: matches.opt_str("lldb-python").unwrap(),
         docck_python: matches.opt_str("docck-python").unwrap(),
         valgrind_path: matches.opt_str("valgrind-path"),
@@ -210,7 +210,7 @@ pub fn log_config(config: &Config) {
     logv(c, format!("compile_lib_path: {:?}", config.compile_lib_path));
     logv(c, format!("run_lib_path: {:?}", config.run_lib_path));
     logv(c, format!("rustc_path: {:?}", config.rustc_path.display()));
-    logv(c, format!("rustdoc_path: {:?}", config.rustdoc_path.display()));
+    logv(c, format!("rustdoc_path: {:?}", config.rustdoc_path));
     logv(c, format!("src_base: {:?}", config.src_base.display()));
     logv(c, format!("build_base: {:?}", config.build_base.display()));
     logv(c, format!("stage_id: {}", config.stage_id));

src/tools/compiletest/src/runtest.rs

@@ -1192,7 +1192,8 @@ actual:\n\
                             self.testpaths.file.to_str().unwrap().to_owned()];
         args.extend(self.props.compile_flags.iter().cloned());
         let args = ProcArgs {
-            prog: self.config.rustdoc_path.to_str().unwrap().to_owned(),
+            prog: self.config.rustdoc_path
+                .as_ref().expect("--rustdoc-path passed").to_str().unwrap().to_owned(),
             args: args,
         };
         self.compose_and_run_compiler(args, None)
@@ -2163,7 +2164,8 @@ actual:\n\
            .env("S", src_root)
            .env("RUST_BUILD_STAGE", &self.config.stage_id)
            .env("RUSTC", cwd.join(&self.config.rustc_path))
-           .env("RUSTDOC", cwd.join(&self.config.rustdoc_path))
+           .env("RUSTDOC",
+               cwd.join(&self.config.rustdoc_path.as_ref().expect("--rustdoc-path passed")))
            .env("TMPDIR", &tmpdir)
            .env("LD_LIB_PATH_ENVVAR", procsrv::dylib_env_var())
            .env("HOST_RPATH_DIR", cwd.join(&self.config.compile_lib_path))