Replace every Vec in Target(Options) with it's Cow equivalent

Author: Urgau

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -674,10 +674,10 @@ fn link_natively<'a, B: ArchiveBuilder<'a>>(
 
     linker::disable_localization(&mut cmd);
 
-    for &(ref k, ref v) in &sess.target.link_env {
+    for &(ref k, ref v) in sess.target.link_env.iter() {
         cmd.env(k.as_ref(), v.as_ref());
     }
-    for k in &sess.target.link_env_remove {
+    for k in sess.target.link_env_remove.iter() {
         cmd.env_remove(k.as_ref());
     }
 

compiler/rustc_serialize/src/json.rs

@@ -2247,6 +2247,15 @@ impl<A: ToJson> ToJson for Vec<A> {
     }
 }
 
+impl<'a, A: ToJson> ToJson for Cow<'a, [A]>
+where
+    [A]: ToOwned,
+{
+    fn to_json(&self) -> Json {
+        Json::Array(self.iter().map(|elt| elt.to_json()).collect())
+    }
+}
+
 impl<T: ToString, A: ToJson> ToJson for BTreeMap<T, A> {
     fn to_json(&self) -> Json {
         let mut d = BTreeMap::new();

compiler/rustc_session/src/config.rs

@@ -956,7 +956,7 @@ fn default_configuration(sess: &Session) -> CrateConfig {
     ret.reserve(7); // the minimum number of insertions
     // Target bindings.
     ret.insert((sym::target_os, Some(Symbol::intern(os))));
-    for fam in &sess.target.families {
+    for fam in sess.target.families.iter() {
         ret.insert((sym::target_family, Some(Symbol::intern(fam))));
         if fam == "windows" {
             ret.insert((sym::windows, None));

compiler/rustc_target/src/spec/aarch64_apple_darwin.rs

@@ -9,7 +9,7 @@ pub fn target() -> Target {
     base.supported_sanitizers = SanitizerSet::ADDRESS | SanitizerSet::CFI | SanitizerSet::THREAD;
 
     base.pre_link_args.insert(LinkerFlavor::Gcc, vec!["-arch".into(), "arm64".into()]);
-    base.link_env_remove.extend(super::apple_base::macos_link_env_remove());
+    base.link_env_remove.to_mut().extend(super::apple_base::macos_link_env_remove());
 
     // Clang automatically chooses a more specific target based on
     // MACOSX_DEPLOYMENT_TARGET.  To enable cross-language LTO to work

compiler/rustc_target/src/spec/apple_base.rs

@@ -2,6 +2,8 @@ use std::{borrow::Cow, env};
 
 use crate::spec::{FramePointer, LldFlavor, SplitDebuginfo, TargetOptions};
 
+use super::cvs;
+
 pub fn opts(os: &'static str) -> TargetOptions {
     // ELF TLS is only available in macOS 10.7+. If you try to compile for 10.6
     // either the linker will complain if it is used or the binary will end up
@@ -26,7 +28,7 @@ pub fn opts(os: &'static str) -> TargetOptions {
         dynamic_linking: true,
         linker_is_gnu: false,
         executables: true,
-        families: vec!["unix".into()],
+        families: cvs!["unix"],
         is_like_osx: true,
         dwarf_version: Some(2),
         frame_pointer: FramePointer::Always,
@@ -51,7 +53,7 @@ pub fn opts(os: &'static str) -> TargetOptions {
         // this environment variable too in recent versions.
         //
         // For some more info see the commentary on #47086
-        link_env: vec![("ZERO_AR_DATE".into(), "1".into())],
+        link_env: Cow::Borrowed(&[(Cow::Borrowed("ZERO_AR_DATE"), Cow::Borrowed("1"))]),
 
         ..Default::default()
     }

compiler/rustc_target/src/spec/apple_sdk_base.rs

@@ -1,4 +1,4 @@
-use crate::spec::TargetOptions;
+use crate::{spec::cvs, spec::TargetOptions};
 use std::borrow::Cow;
 
 use Arch::*;
@@ -36,12 +36,12 @@ fn target_cpu(arch: Arch) -> &'static str {
     }
 }
 
-fn link_env_remove(arch: Arch) -> Vec<Cow<'static, str>> {
+fn link_env_remove(arch: Arch) -> Cow<'static, [Cow<'static, str>]> {
     match arch {
         Armv7 | Armv7s | Arm64 | I386 | X86_64 | Arm64_sim => {
-            vec!["MACOSX_DEPLOYMENT_TARGET".into()]
+            cvs!["MACOSX_DEPLOYMENT_TARGET"]
         }
-        X86_64_macabi | Arm64_macabi => vec!["IPHONEOS_DEPLOYMENT_TARGET".into()],
+        X86_64_macabi | Arm64_macabi => cvs!["IPHONEOS_DEPLOYMENT_TARGET"],
     }
 }
 

compiler/rustc_target/src/spec/armv6k_nintendo_3ds.rs

@@ -1,5 +1,7 @@
 use crate::spec::{LinkArgs, LinkerFlavor, RelocModel, Target, TargetOptions};
 
+use super::cvs;
+
 /// A base target for Nintendo 3DS devices using the devkitARM toolchain.
 ///
 /// Requires the devkitARM toolchain for 3DS targets on the host system.
@@ -30,7 +32,7 @@ pub fn target() -> Target {
             linker_flavor: LinkerFlavor::Gcc,
             cpu: "mpcore".into(),
             executables: true,
-            families: vec!["unix".into()],
+            families: cvs!["unix"],
             linker: Some("arm-none-eabi-gcc".into()),
             relocation_model: RelocModel::Static,
             features: "+vfp2".into(),

compiler/rustc_target/src/spec/dragonfly_base.rs

@@ -1,11 +1,13 @@
 use crate::spec::{RelroLevel, TargetOptions};
 
+use super::cvs;
+
 pub fn opts() -> TargetOptions {
     TargetOptions {
         os: "dragonfly".into(),
         dynamic_linking: true,
         executables: true,
-        families: vec!["unix".into()],
+        families: cvs!["unix"],
         has_rpath: true,
         position_independent_executables: true,
         relro_level: RelroLevel::Full,

compiler/rustc_target/src/spec/freebsd_base.rs

@@ -1,11 +1,13 @@
 use crate::spec::{RelroLevel, TargetOptions};
 
+use super::cvs;
+
 pub fn opts() -> TargetOptions {
     TargetOptions {
         os: "freebsd".into(),
         dynamic_linking: true,
         executables: true,
-        families: vec!["unix".into()],
+        families: cvs!["unix"],
         has_rpath: true,
         position_independent_executables: true,
         relro_level: RelroLevel::Full,

compiler/rustc_target/src/spec/fuchsia_base.rs

@@ -1,5 +1,7 @@
 use crate::spec::{crt_objects, LinkArgs, LinkOutputKind, LinkerFlavor, LldFlavor, TargetOptions};
 
+use super::cvs;
+
 pub fn opts() -> TargetOptions {
     let mut pre_link_args = LinkArgs::new();
     pre_link_args.insert(
@@ -25,7 +27,7 @@ pub fn opts() -> TargetOptions {
         linker: Some("rust-lld".into()),
         dynamic_linking: true,
         executables: true,
-        families: vec!["unix".into()],
+        families: cvs!["unix"],
         is_like_fuchsia: true,
         pre_link_args,
         pre_link_objects: crt_objects::new(&[