add cosmopolitan libc support

Author: io12

compiler/rustc_target/src/spec/base/cosmo.rs

@@ -0,0 +1,34 @@
+use crate::spec::{
+    Cc, FramePointer, LinkerFlavor, Lld, RelocModel, StackProbeType, TargetOptions, cvs,
+};
+
+pub(crate) fn opts() -> TargetOptions {
+    TargetOptions {
+        os: "cosmo".into(),
+        families: cvs!["unix"],
+        plt_by_default: false,
+        requires_uwtable: false,
+        dynamic_linking: false,
+        executables: true,
+        exe_suffix: ".com.dbg".into(),
+        emit_debug_gdb_scripts: false,
+        crt_static_default: true,
+        crt_static_respected: true,
+        allows_weak_linkage: true,
+        has_rpath: false,
+        has_thread_local: false,
+        trap_unreachable: true,
+        position_independent_executables: false,
+        static_position_independent_executables: false,
+        relocation_model: RelocModel::Static,
+        disable_redzone: true,
+        frame_pointer: FramePointer::Always,
+        requires_lto: false,
+        eh_frame_header: false,
+        no_default_libraries: true,
+        max_atomic_width: Some(64),
+        linker_flavor: LinkerFlavor::Gnu(Cc::Yes, Lld::No),
+        stack_probes: StackProbeType::None,
+        ..Default::default()
+    }
+}

compiler/rustc_target/src/spec/base/mod.rs

@@ -3,6 +3,7 @@ pub(crate) mod android;
 pub mod apple;
 pub(crate) mod avr;
 pub(crate) mod bpf;
+pub(crate) mod cosmo;
 pub(crate) mod cygwin;
 pub(crate) mod dragonfly;
 pub(crate) mod freebsd;

compiler/rustc_target/src/spec/mod.rs

@@ -2092,6 +2092,9 @@ supported_targets! {
     ("x86_64-lynx-lynxos178", x86_64_lynx_lynxos178),
 
     ("x86_64-pc-cygwin", x86_64_pc_cygwin),
+
+    ("x86_64-unknown-cosmo", x86_64_unknown_cosmo),
+    ("aarch64-unknown-cosmo", aarch64_unknown_cosmo),
 }
 
 /// Cow-Vec-Str: Cow<'static, [Cow<'static, str>]>

compiler/rustc_target/src/spec/targets/aarch64_unknown_cosmo.rs

@@ -0,0 +1,25 @@
+use crate::spec::{Cc, LinkerFlavor, Lld, Target, TargetMetadata, base};
+
+pub(crate) fn target() -> Target {
+    let mut base = base::cosmo::opts();
+
+    base.linker = Some("aarch64-unknown-cosmo-cc".into());
+    base.features = "+reserve-x28".into();
+
+    base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-static"]);
+
+    Target {
+        llvm_target: "aarch64-unknown-cosmo".into(),
+        metadata: TargetMetadata {
+            description: Some("64-bit Cosmopolitan Libc".into()),
+            tier: Some(3),
+            host_tools: Some(true),
+            std: Some(true),
+        },
+        pointer_width: 64,
+        data_layout:
+            "e-m:e-p270:32:32-p271:32:32-p272:64:64-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128-Fn32".into(),
+        arch: "aarch64".into(),
+        options: base,
+    }
+}

compiler/rustc_target/src/spec/targets/x86_64_unknown_cosmo.rs

@@ -0,0 +1,28 @@
+use crate::spec::{Cc, LinkerFlavor, Lld, Target, TargetMetadata, base};
+
+pub(crate) fn target() -> Target {
+    let mut base = base::cosmo::opts();
+
+    base.cpu = "x86-64".into();
+    base.linker = Some("x86_64-unknown-cosmo-cc".into());
+
+    base.add_pre_link_args(
+        LinkerFlavor::Gnu(Cc::Yes, Lld::No),
+        &["-m64", "-static", "-pg", "-mnop-mcount"],
+    );
+
+    Target {
+        llvm_target: "x86_64-unknown-cosmo".into(),
+        metadata: TargetMetadata {
+            description: Some("64-bit Cosmopolitan Libc".into()),
+            tier: Some(3),
+            host_tools: Some(true),
+            std: Some(true),
+        },
+        pointer_width: 64,
+        data_layout:
+            "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128".into(),
+        arch: "x86_64".into(),
+        options: base,
+    }
+}

compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_cosmopolitan.rs

@@ -0,0 +1 @@
+

library/Cargo.lock

@@ -142,8 +142,6 @@ dependencies = [
 [[package]]
 name = "libc"
 version = "0.2.172"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d750af042f7ef4f724306de029d18836c26c1765a54a6a3f094cbd23a7267ffa"
 dependencies = [
  "rustc-std-workspace-core",
 ]

library/Cargo.toml

@@ -51,3 +51,4 @@ rustc-std-workspace-core = { path = 'rustc-std-workspace-core' }
 rustc-std-workspace-alloc = { path = 'rustc-std-workspace-alloc' }
 rustc-std-workspace-std = { path = 'rustc-std-workspace-std' }
 compiler_builtins = { path = "compiler-builtins/compiler-builtins" }
+libc = { path = 'TODO change to fork' }

library/core/src/ffi/primitives.rs

@@ -109,6 +109,7 @@ mod c_char_definition {
             not(windows),
             not(target_vendor = "apple"),
             not(target_os = "vita"),
+            not(target_os = "cosmo"),
             any(
                 target_arch = "aarch64",
                 target_arch = "arm",

library/std/Cargo.toml

@@ -169,4 +169,5 @@ check-cfg = [
     'cfg(target_has_reliable_f16_math)',
     'cfg(target_has_reliable_f128)',
     'cfg(target_has_reliable_f128_math)',
+    # 'cfg(target_os = "cosmo")',
 ]

library/std/build.rs

@@ -52,6 +52,7 @@ fn main() {
         || target_os == "rtems"
         || target_os == "nuttx"
         || target_os == "cygwin"
+        || target_os == "cosmo"
 
         // See src/bootstrap/src/core/build_steps/synthetic_targets.rs
         || env::var("RUSTC_BOOTSTRAP_SYNTHETIC_TARGET").is_ok()

library/std/src/fs/tests.rs

@@ -491,7 +491,7 @@ fn file_test_io_read_write_at() {
 }
 
 #[test]
-#[cfg(unix)]
+#[cfg(all(unix, not(target_os = "cosmo")))]
 fn set_get_unix_permissions() {
     use crate::os::unix::fs::PermissionsExt;
 

library/std/src/io/copy/tests.rs

@@ -126,7 +126,7 @@ mod io_benches {
     use crate::io::prelude::*;
 
     #[bench]
-    #[cfg_attr(target_os = "emscripten", ignore)] // no /dev
+    #[cfg_attr(any(target_os = "emscripten", target_os = "cosmo"), ignore)] // no /dev
     fn bench_copy_buf_reader(b: &mut Bencher) {
         let mut file_in = File::open("/dev/zero").expect("opening /dev/zero failed");
         // use dyn to avoid specializations unrelated to readbuf