From 7219ba1c9accbad9b530d312fd9a9f69330c93da Mon Sep 17 00:00:00 2001
From: Samuel Holland <samuel@sholland.org>
Date: Sun, 3 May 2020 17:53:33 +0200
Subject: [PATCH 02/15] Remove -nostdlib and musl_root from musl targets

extended by various void contributors to match our musl setup

diff --git a/compiler/rustc_target/src/spec/base/linux_musl.rs b/compiler/rustc_target/src/spec/base/linux_musl.rs
index 1a854fe36..7b0cc7b55 100644
--- a/compiler/rustc_target/src/spec/base/linux_musl.rs
+++ b/compiler/rustc_target/src/spec/base/linux_musl.rs
@@ -1,12 +1,9 @@
-use crate::spec::{LinkSelfContainedDefault, TargetOptions, base, crt_objects};
+use crate::spec::{base, TargetOptions};
 
 pub(crate) fn opts() -> TargetOptions {
     let mut base = base::linux::opts();
 
     base.env = "musl".into();
-    base.pre_link_objects_self_contained = crt_objects::pre_musl_self_contained();
-    base.post_link_objects_self_contained = crt_objects::post_musl_self_contained();
-    base.link_self_contained = LinkSelfContainedDefault::InferredForMusl;
 
     base
 }
diff --git a/compiler/rustc_target/src/spec/crt_objects.rs b/compiler/rustc_target/src/spec/crt_objects.rs
index e3b6430a4..13a96e2cb 100644
--- a/compiler/rustc_target/src/spec/crt_objects.rs
+++ b/compiler/rustc_target/src/spec/crt_objects.rs
@@ -62,28 +62,6 @@ pub(super) fn all(obj: &'static str) -> CrtObjects {
     ])
 }
 
-pub(super) fn pre_musl_self_contained() -> CrtObjects {
-    new(&[
-        (LinkOutputKind::DynamicNoPicExe, &["crt1.o", "crti.o", "crtbegin.o"]),
-        (LinkOutputKind::DynamicPicExe, &["Scrt1.o", "crti.o", "crtbeginS.o"]),
-        (LinkOutputKind::StaticNoPicExe, &["crt1.o", "crti.o", "crtbegin.o"]),
-        (LinkOutputKind::StaticPicExe, &["rcrt1.o", "crti.o", "crtbeginS.o"]),
-        (LinkOutputKind::DynamicDylib, &["crti.o", "crtbeginS.o"]),
-        (LinkOutputKind::StaticDylib, &["crti.o", "crtbeginS.o"]),
-    ])
-}
-
-pub(super) fn post_musl_self_contained() -> CrtObjects {
-    new(&[
-        (LinkOutputKind::DynamicNoPicExe, &["crtend.o", "crtn.o"]),
-        (LinkOutputKind::DynamicPicExe, &["crtendS.o", "crtn.o"]),
-        (LinkOutputKind::StaticNoPicExe, &["crtend.o", "crtn.o"]),
-        (LinkOutputKind::StaticPicExe, &["crtendS.o", "crtn.o"]),
-        (LinkOutputKind::DynamicDylib, &["crtendS.o", "crtn.o"]),
-        (LinkOutputKind::StaticDylib, &["crtendS.o", "crtn.o"]),
-    ])
-}
-
 pub(super) fn pre_mingw_self_contained() -> CrtObjects {
     new(&[
         (LinkOutputKind::DynamicNoPicExe, &["crt2.o", "rsbegin.o"]),
diff --git a/compiler/rustc_target/src/spec/targets/aarch64_unknown_linux_musl.rs b/compiler/rustc_target/src/spec/targets/aarch64_unknown_linux_musl.rs
index 4fefdfa5c..bb65048a5 100644
--- a/compiler/rustc_target/src/spec/targets/aarch64_unknown_linux_musl.rs
+++ b/compiler/rustc_target/src/spec/targets/aarch64_unknown_linux_musl.rs
@@ -12,9 +12,6 @@ pub(crate) fn target() -> Target {
         | SanitizerSet::MEMORY
         | SanitizerSet::THREAD;
 
-    // FIXME(compiler-team#422): musl targets should be dynamically linked by default.
-    base.crt_static_default = true;
-
     Target {
         llvm_target: "aarch64-unknown-linux-musl".into(),
         metadata: crate::spec::TargetMetadata {
diff --git a/compiler/rustc_target/src/spec/targets/arm_unknown_linux_musleabihf.rs b/compiler/rustc_target/src/spec/targets/arm_unknown_linux_musleabihf.rs
index 4bbde7667..50f1a8d88 100644
--- a/compiler/rustc_target/src/spec/targets/arm_unknown_linux_musleabihf.rs
+++ b/compiler/rustc_target/src/spec/targets/arm_unknown_linux_musleabihf.rs
@@ -20,8 +20,6 @@ pub(crate) fn target() -> Target {
             features: "+strict-align,+v6,+vfp2,-d32".into(),
             max_atomic_width: Some(64),
             mcount: "\u{1}mcount".into(),
-            // FIXME(compiler-team#422): musl targets should be dynamically linked by default.
-            crt_static_default: true,
             ..base::linux_musl::opts()
         },
     }
diff --git a/compiler/rustc_target/src/spec/targets/armv7_unknown_linux_musleabihf.rs b/compiler/rustc_target/src/spec/targets/armv7_unknown_linux_musleabihf.rs
index 22e49f2f1..28a954758 100644
--- a/compiler/rustc_target/src/spec/targets/armv7_unknown_linux_musleabihf.rs
+++ b/compiler/rustc_target/src/spec/targets/armv7_unknown_linux_musleabihf.rs
@@ -23,8 +23,6 @@ pub(crate) fn target() -> Target {
             features: "+v7,+vfp3,-d32,+thumb2,-neon".into(),
             max_atomic_width: Some(64),
             mcount: "\u{1}mcount".into(),
-            // FIXME(compiler-team#422): musl targets should be dynamically linked by default.
-            crt_static_default: true,
             ..base::linux_musl::opts()
         },
     }
diff --git a/compiler/rustc_target/src/spec/targets/i686_unknown_linux_musl.rs b/compiler/rustc_target/src/spec/targets/i686_unknown_linux_musl.rs
index 3d25c951e..f509c9825 100644
--- a/compiler/rustc_target/src/spec/targets/i686_unknown_linux_musl.rs
+++ b/compiler/rustc_target/src/spec/targets/i686_unknown_linux_musl.rs
@@ -9,8 +9,6 @@ pub(crate) fn target() -> Target {
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m32", "-Wl,-melf_i386"]);
     base.stack_probes = StackProbeType::Inline;
-    // FIXME(compiler-team#422): musl targets should be dynamically linked by default.
-    base.crt_static_default = true;
 
     // The unwinder used by i686-unknown-linux-musl, the LLVM libunwind
     // implementation, apparently relies on frame pointers existing... somehow.
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_musl.rs b/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_musl.rs
index 8dcdc5be8..8be0f335d 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_musl.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_musl.rs
@@ -14,8 +14,6 @@ pub(crate) fn target() -> Target {
         | SanitizerSet::MEMORY
         | SanitizerSet::THREAD;
     base.supports_xray = true;
-    // FIXME(compiler-team#422): musl targets should be dynamically linked by default.
-    base.crt_static_default = true;
 
     Target {
         llvm_target: "x86_64-unknown-linux-musl".into(),
diff --git a/config.example.toml b/config.example.toml
index f5395375a..3aa6e21ac 100644
--- a/config.example.toml
+++ b/config.example.toml
@@ -625,14 +625,6 @@
 # behavior -- this may lead to miscompilations or other bugs.
 #description = ""
 
-# The root location of the musl installation directory. The library directory
-# will also need to contain libunwind.a for an unwinding implementation. Note
-# that this option only makes sense for musl targets that produce statically
-# linked binaries.
-#
-# Defaults to /usr on musl hosts. Has no default otherwise.
-#musl-root = <platform specific> (path)
-
 # By default the `rustc` executable is built with `-Wl,-rpath` flags on Unix
 # platforms to ensure that the compiler is usable by default from the build
 # directory (as it links to a number of dynamic libraries). This may not be
diff --git a/src/bootstrap/configure.py b/src/bootstrap/configure.py
index ac971a64d..f7367c8da 100755
--- a/src/bootstrap/configure.py
+++ b/src/bootstrap/configure.py
@@ -179,76 +179,6 @@ v("llvm-config", None, "set path to llvm-config")
 v("llvm-filecheck", None, "set path to LLVM's FileCheck utility")
 v("python", "build.python", "set path to python")
 v("android-ndk", "build.android-ndk", "set path to Android NDK")
-v(
-    "musl-root",
-    "target.x86_64-unknown-linux-musl.musl-root",
-    "MUSL root installation directory (deprecated)",
-)
-v(
-    "musl-root-x86_64",
-    "target.x86_64-unknown-linux-musl.musl-root",
-    "x86_64-unknown-linux-musl install directory",
-)
-v(
-    "musl-root-i586",
-    "target.i586-unknown-linux-musl.musl-root",
-    "i586-unknown-linux-musl install directory",
-)
-v(
-    "musl-root-i686",
-    "target.i686-unknown-linux-musl.musl-root",
-    "i686-unknown-linux-musl install directory",
-)
-v(
-    "musl-root-arm",
-    "target.arm-unknown-linux-musleabi.musl-root",
-    "arm-unknown-linux-musleabi install directory",
-)
-v(
-    "musl-root-armhf",
-    "target.arm-unknown-linux-musleabihf.musl-root",
-    "arm-unknown-linux-musleabihf install directory",
-)
-v(
-    "musl-root-armv5te",
-    "target.armv5te-unknown-linux-musleabi.musl-root",
-    "armv5te-unknown-linux-musleabi install directory",
-)
-v(
-    "musl-root-armv7",
-    "target.armv7-unknown-linux-musleabi.musl-root",
-    "armv7-unknown-linux-musleabi install directory",
-)
-v(
-    "musl-root-armv7hf",
-    "target.armv7-unknown-linux-musleabihf.musl-root",
-    "armv7-unknown-linux-musleabihf install directory",
-)
-v(
-    "musl-root-aarch64",
-    "target.aarch64-unknown-linux-musl.musl-root",
-    "aarch64-unknown-linux-musl install directory",
-)
-v(
-    "musl-root-mips",
-    "target.mips-unknown-linux-musl.musl-root",
-    "mips-unknown-linux-musl install directory",
-)
-v(
-    "musl-root-mipsel",
-    "target.mipsel-unknown-linux-musl.musl-root",
-    "mipsel-unknown-linux-musl install directory",
-)
-v(
-    "musl-root-mips64",
-    "target.mips64-unknown-linux-muslabi64.musl-root",
-    "mips64-unknown-linux-muslabi64 install directory",
-)
-v(
-    "musl-root-mips64el",
-    "target.mips64el-unknown-linux-muslabi64.musl-root",
-    "mips64el-unknown-linux-muslabi64 install directory",
-)
 v(
     "musl-root-powerpc64le",
     "target.powerpc64le-unknown-linux-musl.musl-root",
diff --git a/src/bootstrap/src/core/build_steps/compile.rs b/src/bootstrap/src/core/build_steps/compile.rs
index 479327d63..115b3eb0a 100644
--- a/src/bootstrap/src/core/build_steps/compile.rs
+++ b/src/bootstrap/src/core/build_steps/compile.rs
@@ -333,39 +333,7 @@ fn copy_self_contained_objects(
     let mut target_deps = vec![];
 
     // Copies the libc and CRT objects.
-    //
-    // rustc historically provides a more self-contained installation for musl targets
-    // not requiring the presence of a native musl toolchain. For example, it can fall back
-    // to using gcc from a glibc-targeting toolchain for linking.
-    // To do that we have to distribute musl startup objects as a part of Rust toolchain
-    // and link with them manually in the self-contained mode.
-    if target.needs_crt_begin_end() {
-        let srcdir = builder.musl_libdir(target).unwrap_or_else(|| {
-            panic!("Target {:?} does not have a \"musl-libdir\" key", target.triple)
-        });
-        for &obj in &["libc.a", "crt1.o", "Scrt1.o", "rcrt1.o", "crti.o", "crtn.o"] {
-            copy_and_stamp(
-                builder,
-                &libdir_self_contained,
-                &srcdir,
-                obj,
-                &mut target_deps,
-                DependencyType::TargetSelfContained,
-            );
-        }
-        let crt_path = builder.ensure(llvm::CrtBeginEnd { target });
-        for &obj in &["crtbegin.o", "crtbeginS.o", "crtend.o", "crtendS.o"] {
-            let src = crt_path.join(obj);
-            let target = libdir_self_contained.join(obj);
-            builder.copy_link(&src, &target);
-            target_deps.push((target, DependencyType::TargetSelfContained));
-        }
-
-        if !target.starts_with("s390x") {
-            let libunwind_path = copy_llvm_libunwind(builder, target, &libdir_self_contained);
-            target_deps.push((libunwind_path, DependencyType::TargetSelfContained));
-        }
-    } else if target.contains("-wasi") {
+    if target.contains("-wasi") {
         let srcdir = builder.wasi_libdir(target).unwrap_or_else(|| {
             panic!(
                 "Target {:?} does not have a \"wasi-root\" key in Config.toml \
@@ -573,15 +541,6 @@ pub fn std_cargo(builder: &Builder<'_>, target: TargetSelection, stage: u32, car
             .arg("--manifest-path")
             .arg(builder.src.join("library/sysroot/Cargo.toml"));
 
-        // Help the libc crate compile by assisting it in finding various
-        // sysroot native libraries.
-        if target.contains("musl") {
-            if let Some(p) = builder.musl_libdir(target) {
-                let root = format!("native={}", p.to_str().unwrap());
-                cargo.rustflag("-L").rustflag(&root);
-            }
-        }
-
         if target.contains("-wasi") {
             if let Some(dir) = builder.wasi_libdir(target) {
                 let root = format!("native={}", dir.to_str().unwrap());
diff --git a/src/bootstrap/src/core/config/config.rs b/src/bootstrap/src/core/config/config.rs
index 65f286a05..f12d57b14 100644
--- a/src/bootstrap/src/core/config/config.rs
+++ b/src/bootstrap/src/core/config/config.rs
@@ -350,7 +350,6 @@ pub struct Config {
     pub print_step_rusage: bool,
 
     // Fallback musl-root for all targets
-    pub musl_root: Option<PathBuf>,
     pub prefix: Option<PathBuf>,
     pub sysconfdir: Option<PathBuf>,
     pub datadir: Option<PathBuf>,
@@ -635,8 +634,6 @@ pub struct Target {
     pub profiler: Option<StringOrBool>,
     pub rpath: Option<bool>,
     pub crt_static: Option<bool>,
-    pub musl_root: Option<PathBuf>,
-    pub musl_libdir: Option<PathBuf>,
     pub wasi_root: Option<PathBuf>,
     pub qemu_rootfs: Option<PathBuf>,
     pub runner: Option<String>,
@@ -1171,7 +1168,6 @@ define_config! {
         default_linker: Option<String> = "default-linker",
         channel: Option<String> = "channel",
         description: Option<String> = "description",
-        musl_root: Option<String> = "musl-root",
         rpath: Option<bool> = "rpath",
         strip: Option<bool> = "strip",
         frame_pointers: Option<bool> = "frame-pointers",
@@ -1226,8 +1222,6 @@ define_config! {
         profiler: Option<StringOrBool> = "profiler",
         rpath: Option<bool> = "rpath",
         crt_static: Option<bool> = "crt-static",
-        musl_root: Option<String> = "musl-root",
-        musl_libdir: Option<String> = "musl-libdir",
         wasi_root: Option<String> = "wasi-root",
         qemu_rootfs: Option<String> = "qemu-rootfs",
         no_std: Option<bool> = "no-std",
@@ -1821,7 +1815,6 @@ impl Config {
                 default_linker,
                 channel: _, // already handled above
                 description,
-                musl_root,
                 rpath,
                 verbose_tests,
                 optimize_tests,
@@ -1929,7 +1922,6 @@ impl Config {
             config.llvm_enzyme =
                 llvm_enzyme.unwrap_or(config.channel == "dev" || config.channel == "nightly");
             config.rustc_default_linker = default_linker;
-            config.musl_root = musl_root.map(PathBuf::from);
             config.save_toolstates = save_toolstates.map(PathBuf::from);
             set(
                 &mut config.deny_warnings,
@@ -2152,8 +2144,6 @@ impl Config {
                 target.ranlib = cfg.ranlib.map(PathBuf::from);
                 target.linker = cfg.linker.map(PathBuf::from);
                 target.crt_static = cfg.crt_static;
-                target.musl_root = cfg.musl_root.map(PathBuf::from);
-                target.musl_libdir = cfg.musl_libdir.map(PathBuf::from);
                 target.wasi_root = cfg.wasi_root.map(PathBuf::from);
                 target.qemu_rootfs = cfg.qemu_rootfs.map(PathBuf::from);
                 target.runner = cfg.runner;
@@ -3295,7 +3285,6 @@ fn check_incompatible_options_for_ci_rustc(
         debuginfo_level_tools: _,
         debuginfo_level_tests: _,
         backtrace: _,
-        musl_root: _,
         verbose_tests: _,
         optimize_tests: _,
         codegen_tests: _,
diff --git a/src/bootstrap/src/core/sanity.rs b/src/bootstrap/src/core/sanity.rs
index 9e4a0816e..36c3b5901 100644
--- a/src/bootstrap/src/core/sanity.rs
+++ b/src/bootstrap/src/core/sanity.rs
@@ -11,7 +11,7 @@
 use std::collections::{HashMap, HashSet};
 use std::ffi::{OsStr, OsString};
 use std::path::PathBuf;
-use std::{env, fs};
+use std::env;
 
 use crate::Build;
 #[cfg(not(test))]
@@ -325,28 +325,6 @@ than building it.
             continue;
         }
 
-        // Make sure musl-root is valid.
-        if target.contains("musl") && !target.contains("unikraft") {
-            // If this is a native target (host is also musl) and no musl-root is given,
-            // fall back to the system toolchain in /usr before giving up
-            if build.musl_root(*target).is_none() && build.is_builder_target(target) {
-                let target = build.config.target_config.entry(*target).or_default();
-                target.musl_root = Some("/usr".into());
-            }
-            match build.musl_libdir(*target) {
-                Some(libdir) => {
-                    if fs::metadata(libdir.join("libc.a")).is_err() {
-                        panic!("couldn't find libc.a in musl libdir: {}", libdir.display());
-                    }
-                }
-                None => panic!(
-                    "when targeting MUSL either the rust.musl-root \
-                            option or the target.$TARGET.musl-root option must \
-                            be specified in config.toml"
-                ),
-            }
-        }
-
         if need_cmake && target.is_msvc() {
             // There are three builds of cmake on windows: MSVC, MinGW, and
             // Cygwin. The Cygwin build does not have generators for Visual
diff --git a/src/bootstrap/src/lib.rs b/src/bootstrap/src/lib.rs
index 21b02a3b5..491d924d4 100644
--- a/src/bootstrap/src/lib.rs
+++ b/src/bootstrap/src/lib.rs
@@ -1322,25 +1322,6 @@ Executed at: {executed_at}"#,
         }
     }
 
-    /// Returns the "musl root" for this `target`, if defined
-    fn musl_root(&self, target: TargetSelection) -> Option<&Path> {
-        self.config
-            .target_config
-            .get(&target)
-            .and_then(|t| t.musl_root.as_ref())
-            .or(self.config.musl_root.as_ref())
-            .map(|p| &**p)
-    }
-
-    /// Returns the "musl libdir" for this `target`.
-    fn musl_libdir(&self, target: TargetSelection) -> Option<PathBuf> {
-        let t = self.config.target_config.get(&target)?;
-        if let libdir @ Some(_) = &t.musl_libdir {
-            return libdir.clone();
-        }
-        self.musl_root(target).map(|root| root.join("lib"))
-    }
-
     /// Returns the `lib` directory for the WASI target specified, if
     /// configured.
     ///
diff --git a/src/bootstrap/src/utils/cc_detect.rs b/src/bootstrap/src/utils/cc_detect.rs
index 45797c127..12393b659 100644
--- a/src/bootstrap/src/utils/cc_detect.rs
+++ b/src/bootstrap/src/utils/cc_detect.rs
@@ -210,30 +210,6 @@ fn default_compiler(
             }
         }
 
-        "mips-unknown-linux-musl" if compiler == Language::C => {
-            if cfg.get_compiler().path().to_str() == Some("gcc") {
-                Some(PathBuf::from("mips-linux-musl-gcc"))
-            } else {
-                None
-            }
-        }
-        "mipsel-unknown-linux-musl" if compiler == Language::C => {
-            if cfg.get_compiler().path().to_str() == Some("gcc") {
-                Some(PathBuf::from("mipsel-linux-musl-gcc"))
-            } else {
-                None
-            }
-        }
-
-        t if t.contains("musl") && compiler == Language::C => {
-            if let Some(root) = build.musl_root(target) {
-                let guess = root.join("bin/musl-gcc");
-                if guess.exists() { Some(guess) } else { None }
-            } else {
-                None
-            }
-        }
-
         t if t.contains("-wasi") => {
             let root = PathBuf::from(std::env::var_os("WASI_SDK_PATH")?);
             let compiler = match compiler {