rustc_target: Add some more target spec sanity checking

compiler/rustc_target/src/spec/aarch64_nintendo_switch_freestanding.rs

@@ -18,7 +18,6 @@ pub fn target() -> Target {
             panic_strategy: PanicStrategy::Abort,
             position_independent_executables: true,
             dynamic_linking: true,
-            executables: true,
             relro_level: RelroLevel::Off,
             ..Default::default()
         },

compiler/rustc_target/src/spec/android_base.rs

@@ -4,7 +4,6 @@ pub fn opts() -> TargetOptions {
     let mut base = super::linux_base::opts();
     base.os = "android".into();
     base.default_dwarf_version = 2;
-    base.position_independent_executables = true;
     base.has_thread_local = false;
     // This is for backward compatibility, see https://github.com/rust-lang/rust/issues/49867
     // for context. (At that time, there was no `-C force-unwind-tables`, so the only solution

compiler/rustc_target/src/spec/apple_base.rs

@@ -1,40 +1,37 @@
 use std::{borrow::Cow, env};
 
-use crate::spec::{cvs, DebuginfoKind, FramePointer, SplitDebuginfo, TargetOptions};
+use crate::spec::{cvs, DebuginfoKind, FramePointer, SplitDebuginfo, StaticCow, TargetOptions};
 use crate::spec::{LinkArgs, LinkerFlavor, LldFlavor};
 
 fn pre_link_args(os: &'static str, arch: &'static str, abi: &'static str) -> LinkArgs {
-    let mut args = LinkArgs::new();
-
-    let platform_name = match abi {
-        "sim" => format!("{}-simulator", os),
-        "macabi" => "mac-catalyst".to_string(),
-        _ => os.to_string(),
+    let platform_name: StaticCow<str> = match abi {
+        "sim" => format!("{}-simulator", os).into(),
+        "macabi" => "mac-catalyst".into(),
+        _ => os.into(),
     };
 
-    let platform_version = match os.as_ref() {
+    let platform_version: StaticCow<str> = match os.as_ref() {
         "ios" => ios_lld_platform_version(),
         "tvos" => tvos_lld_platform_version(),
         "watchos" => watchos_lld_platform_version(),
         "macos" => macos_lld_platform_version(arch),
         _ => unreachable!(),
-    };
-
-    if abi != "macabi" {
-        args.insert(LinkerFlavor::Gcc, vec!["-arch".into(), arch.into()]);
     }
+    .into();
 
-    args.insert(
+    let mut args = TargetOptions::link_args(
         LinkerFlavor::Lld(LldFlavor::Ld64),
-        vec![
-            "-arch".into(),
-            arch.into(),
-            "-platform_version".into(),
-            platform_name.into(),
-            platform_version.clone().into(),
-            platform_version.into(),
-        ],
+        &["-arch", arch, "-platform_version"],
     );
+    // Manually add owned args unsupported by link arg building helpers.
+    args.entry(LinkerFlavor::Lld(LldFlavor::Ld64)).or_default().extend([
+        platform_name,
+        platform_version.clone(),
+        platform_version,
+    ]);
+    if abi != "macabi" {
+        super::add_link_args(&mut args, LinkerFlavor::Gcc, &["-arch", arch]);
+    }
 
     args
 }
@@ -127,7 +124,7 @@ pub fn macos_llvm_target(arch: &str) -> String {
     format!("{}-apple-macosx{}.{}.0", arch, major, minor)
 }
 
-pub fn macos_link_env_remove() -> Vec<Cow<'static, str>> {
+pub fn macos_link_env_remove() -> Vec<StaticCow<str>> {
     let mut env_remove = Vec::with_capacity(2);
     // Remove the `SDKROOT` environment variable if it's clearly set for the wrong platform, which
     // may occur when we're linking a custom build script while targeting iOS for example.

compiler/rustc_target/src/spec/avr_gnu_base.rs

@@ -1,4 +1,4 @@
-use crate::spec::{LinkerFlavor, Target, TargetOptions};
+use crate::spec::{LinkerFlavor, RelocModel, Target, TargetOptions};
 
 /// A base target for AVR devices using the GNU toolchain.
 ///
@@ -21,6 +21,7 @@ pub fn target(target_cpu: &'static str, mmcu: &'static str) -> Target {
             late_link_args: TargetOptions::link_args(LinkerFlavor::Gcc, &["-lgcc"]),
             max_atomic_width: Some(0),
             atomic_cas: false,
+            relocation_model: RelocModel::Static,
             ..TargetOptions::default()
         },
     }

compiler/rustc_target/src/spec/hexagon_unknown_linux_musl.rs

@@ -10,7 +10,6 @@ pub fn target() -> Target {
     base.crt_static_default = false;
     base.has_rpath = true;
     base.linker_is_gnu = false;
-    base.dynamic_linking = true;
 
     base.c_enum_min_bits = 8;
 

compiler/rustc_target/src/spec/l4re_base.rs

@@ -1,4 +1,4 @@
-use crate::spec::{cvs, LinkerFlavor, PanicStrategy, TargetOptions};
+use crate::spec::{cvs, LinkerFlavor, PanicStrategy, RelocModel, TargetOptions};
 
 pub fn opts() -> TargetOptions {
     TargetOptions {
@@ -9,6 +9,7 @@ pub fn opts() -> TargetOptions {
         linker: Some("l4-bender".into()),
         linker_is_gnu: false,
         families: cvs!["unix"],
+        relocation_model: RelocModel::Static,
         ..Default::default()
     }
 }

compiler/rustc_target/src/spec/mod.rs

@@ -837,15 +837,15 @@ impl fmt::Display for StackProtector {
 }
 
 macro_rules! supported_targets {
-    ( $(($( $triple:literal, )+ $module:ident ),)+ ) => {
+    ( $(($triple:literal, $module:ident ),)+ ) => {
         $(mod $module;)+
 
         /// List of supported targets
-        pub const TARGETS: &[&str] = &[$($($triple),+),+];
+        pub const TARGETS: &[&str] = &[$($triple),+];
 
         fn load_builtin(target: &str) -> Option<Target> {
             let mut t = match target {
-                $( $($triple)|+ => $module::target(), )+
+                $( $triple => $module::target(), )+
                 _ => return None,
             };
             t.is_builtin = true;
@@ -861,7 +861,7 @@ macro_rules! supported_targets {
             $(
                 #[test] // `#[test]`
                 fn $module() {
-                    tests_impl::test_target(super::$module::target());
+                    tests_impl::test_target(super::$module::target(), $triple);
                 }
             )+
         }
@@ -1526,7 +1526,7 @@ fn add_link_args(link_args: &mut LinkArgs, flavor: LinkerFlavor, args: &[&'stati
     match flavor {
         LinkerFlavor::Ld => insert(LinkerFlavor::Lld(LldFlavor::Ld)),
         LinkerFlavor::Msvc => insert(LinkerFlavor::Lld(LldFlavor::Link)),
-        LinkerFlavor::Lld(LldFlavor::Wasm) => {}
+        LinkerFlavor::Lld(LldFlavor::Ld64) | LinkerFlavor::Lld(LldFlavor::Wasm) => {}
         LinkerFlavor::Lld(lld_flavor) => {
             panic!("add_link_args: use non-LLD flavor for {:?}", lld_flavor)
         }

compiler/rustc_target/src/spec/powerpc_unknown_freebsd.rs

@@ -1,5 +1,5 @@
 use crate::abi::Endian;
-use crate::spec::{LinkerFlavor, RelocModel, Target, TargetOptions};
+use crate::spec::{LinkerFlavor, Target, TargetOptions};
 
 pub fn target() -> Target {
     let mut base = super::freebsd_base::opts();
@@ -15,7 +15,6 @@ pub fn target() -> Target {
         options: TargetOptions {
             endian: Endian::Big,
             features: "+secure-plt".into(),
-            relocation_model: RelocModel::Pic,
             mcount: "_mcount".into(),
             ..base
         },

compiler/rustc_target/src/spec/tests/tests_impl.rs

@@ -2,18 +2,20 @@ use super::super::*;
 use std::assert_matches::assert_matches;
 
 // Test target self-consistency and JSON encoding/decoding roundtrip.
-pub(super) fn test_target(target: Target) {
-    target.check_consistency();
+pub(super) fn test_target(target: Target, triple: &str) {
+    target.check_consistency(triple);
     assert_eq!(Target::from_json(target.to_json()).map(|(j, _)| j), Ok(target));
 }
 
 impl Target {
-    fn check_consistency(&self) {
+    fn check_consistency(&self, triple: &str) {
         assert_eq!(self.is_like_osx, self.vendor == "apple");
         assert_eq!(self.is_like_solaris, self.os == "solaris" || self.os == "illumos");
         assert_eq!(self.is_like_windows, self.os == "windows" || self.os == "uefi");
         assert_eq!(self.is_like_wasm, self.arch == "wasm32" || self.arch == "wasm64");
-        assert!(self.is_like_windows || !self.is_like_msvc);
+        if self.is_like_msvc {
+            assert!(self.is_like_windows);
+        }
 
         // Check that default linker flavor and lld flavor are compatible
         // with some other key properties.
@@ -94,8 +96,9 @@ impl Target {
                             check_noncc(LinkerFlavor::Ld);
                             check_noncc(LinkerFlavor::Lld(LldFlavor::Ld));
                         }
+                        LldFlavor::Ld64 => check_noncc(LinkerFlavor::Lld(LldFlavor::Ld64)),
                         LldFlavor::Wasm => check_noncc(LinkerFlavor::Lld(LldFlavor::Wasm)),
-                        LldFlavor::Ld64 | LldFlavor::Link => {}
+                        LldFlavor::Link => {}
                     },
                     _ => {}
                 }
@@ -109,20 +112,56 @@ impl Target {
             );
         }
 
-        assert!(
-            (self.pre_link_objects_self_contained.is_empty()
-                && self.post_link_objects_self_contained.is_empty())
-                || self.link_self_contained != LinkSelfContainedDefault::False
-        );
+        if self.link_self_contained == LinkSelfContainedDefault::False {
+            assert!(
+                self.pre_link_objects_self_contained.is_empty()
+                    && self.post_link_objects_self_contained.is_empty()
+            );
+        }
 
         // If your target really needs to deviate from the rules below,
         // except it and document the reasons.
         // Keep the default "unknown" vendor instead.
         assert_ne!(self.vendor, "");
+        assert_ne!(self.os, "");
         if !self.can_use_os_unknown() {
             // Keep the default "none" for bare metal targets instead.
             assert_ne!(self.os, "unknown");
         }
+
+        // Check dynamic linking stuff
+        // BPF: when targeting user space vms (like rbpf), those can load dynamic libraries.
+        if self.os == "none" && self.arch != "bpf" {
+            assert!(!self.dynamic_linking);
+        }
+        if self.only_cdylib
+            || self.crt_static_allows_dylibs
+            || !self.late_link_args_dynamic.is_empty()
+        {
+            assert!(self.dynamic_linking);
+        }
+        // Apparently PIC was slow on wasm at some point, see comments in wasm_base.rs
+        if self.dynamic_linking && !(self.is_like_wasm && self.os != "emscripten") {
+            assert_eq!(self.relocation_model, RelocModel::Pic);
+        }
+        // PIEs are supported but not enabled by default with linuxkernel target.
+        if self.position_independent_executables && !triple.ends_with("-linuxkernel") {
+            assert_eq!(self.relocation_model, RelocModel::Pic);
+        }
+        if self.relocation_model == RelocModel::Pic {
+            assert!(self.dynamic_linking || self.position_independent_executables);
+        }
+        if self.static_position_independent_executables {
+            assert!(self.position_independent_executables);
+        }
+        if self.position_independent_executables {
+            assert!(self.executables);
+        }
+
+        // Check crt static stuff
+        if self.crt_static_default || self.crt_static_allows_dylibs {
+            assert!(self.crt_static_respected);
+        }
     }
 
     // Add your target to the whitelist if it has `std` library

compiler/rustc_target/src/spec/uefi_msvc_base.rs

@@ -9,7 +9,8 @@
 // the timer-interrupt. Device-drivers are required to use polling-based models. Furthermore, all
 // code runs in the same environment, no process separation is supported.
 
-use crate::spec::{LinkerFlavor, LldFlavor, PanicStrategy, StackProbeType, TargetOptions};
+use crate::spec::{LinkerFlavor, LldFlavor, PanicStrategy};
+use crate::spec::{RelocModel, StackProbeType, TargetOptions};
 
 pub fn opts() -> TargetOptions {
     let mut base = super::msvc_base::opts();
@@ -46,6 +47,7 @@ pub fn opts() -> TargetOptions {
         stack_probes: StackProbeType::Call,
         singlethread: true,
         linker: Some("rust-lld".into()),
+        relocation_model: RelocModel::Static,
         ..base
     }
 }

compiler/rustc_target/src/spec/x86_64_unknown_l4re_uclibc.rs

@@ -4,8 +4,6 @@ pub fn target() -> Target {
     let mut base = super::l4re_base::opts();
     base.cpu = "x86-64".into();
     base.max_atomic_width = Some(64);
-    base.crt_static_allows_dylibs = false;
-    base.dynamic_linking = false;
     base.panic_strategy = PanicStrategy::Abort;
 
     Target {

compiler/rustc_target/src/spec/x86_64_unknown_none.rs

@@ -4,10 +4,8 @@
 // `target-cpu` compiler flags to opt-in more hardware-specific
 // features.
 
-use super::{
-    CodeModel, LinkerFlavor, LldFlavor, PanicStrategy, RelocModel, RelroLevel, StackProbeType,
-    Target, TargetOptions,
-};
+use super::{CodeModel, LinkerFlavor, LldFlavor, PanicStrategy};
+use super::{RelroLevel, StackProbeType, Target, TargetOptions};
 
 pub fn target() -> Target {
     let opts = TargetOptions {
@@ -18,7 +16,6 @@ pub fn target() -> Target {
         position_independent_executables: true,
         static_position_independent_executables: true,
         relro_level: RelroLevel::Full,
-        relocation_model: RelocModel::Pic,
         linker_flavor: LinkerFlavor::Lld(LldFlavor::Ld),
         linker: Some("rust-lld".into()),
         features:

src/test/codegen/abi-efiapi.rs

@@ -24,7 +24,7 @@ trait Freeze { }
 #[lang="copy"]
 trait Copy { }
 
-//x86_64: define win64cc void @has_efiapi
+//x86_64: define dso_local win64cc void @has_efiapi
 //i686: define void @has_efiapi
 //aarch64: define dso_local void @has_efiapi
 //arm: define dso_local void @has_efiapi

src/test/codegen/avr/avr-func-addrspace.rs

@@ -77,7 +77,7 @@ fn update_bar_value() {
     }
 }
 
-// CHECK: define void @test(){{.+}}addrspace(1)
+// CHECK: define dso_local void @test(){{.+}}addrspace(1)
 #[no_mangle]
 pub extern "C" fn test() {
     let mut buf = 7;