Remove cupid dependency and env-override-no-avx CI run

Author: sayantn

.github/workflows/main.yml

@@ -35,20 +35,6 @@ jobs:
       run: rustup update nightly --no-self-update && rustup default nightly
     - run: cargo test --manifest-path crates/stdarch-verify/Cargo.toml
 
-  env_override:
-    name: Env Override
-    needs: [style]
-    runs-on: ${{ matrix.os }}
-    strategy:
-      matrix:
-        os: [ubuntu-latest, windows-latest]
-    steps:
-    - uses: actions/checkout@v4
-    - name: Install Rust
-      run: rustup update nightly --no-self-update && rustup default nightly
-    - run: RUST_STD_DETECT_UNSTABLE=avx cargo test --features=std_detect_env_override --manifest-path crates/std_detect/Cargo.toml env_override_no_avx
-      shell: bash
-
   test:
     needs: [style]
     name: Test
@@ -243,7 +229,6 @@ jobs:
     needs:
       - docs
       - verify
-      - env_override
       - test
       - build-std-detect
     runs-on: ubuntu-latest

ci/run.sh

@@ -44,12 +44,8 @@ case ${TARGET} in
     mips-* | mipsel-*)
 	export RUSTFLAGS="${RUSTFLAGS} -C llvm-args=-fast-isel=false"
 	;;
-    # Some of our test dependencies use the deprecated `gcc` crates which is
-    # missing a fix from https://github.com/alexcrichton/cc-rs/pull/627. Apply
-    # the workaround manually here.
     armv7-*eabihf | thumbv7-*eabihf)
         export RUSTFLAGS="${RUSTFLAGS} -Ctarget-feature=+neon"
-        export TARGET_CFLAGS="-mfpu=vfpv3-d16"
         ;;
     # Some of our test dependencies use the deprecated `gcc` crates which
     # doesn't detect RISC-V compilers automatically, so do it manually here.

crates/std_detect/Cargo.toml

@@ -31,14 +31,10 @@ alloc = { version = "1.0.0", optional = true, package = "rustc-std-workspace-all
 [target.'cfg(not(windows))'.dependencies]
 libc = { version = "0.2.0", optional = true, default-features = false }
 
-[dev-dependencies]
-cupid = "0.6.0"
-
 [features]
 default = [ "std_detect_dlsym_getauxval", "std_detect_file_io" ]
 std_detect_file_io = [ "libc" ]
 std_detect_dlsym_getauxval = [ "libc" ]
-std_detect_env_override = [ "libc" ]
 rustc-dep-of-std = [
     "core",
     "compiler_builtins",

crates/std_detect/README.md

@@ -52,8 +52,7 @@ crate from working on applications in which `std` is not available.
 * All `x86`/`x86_64` targets are supported on all platforms by querying the
   `cpuid` instruction directly for the features supported by the hardware and
   the operating system. `std_detect` assumes that the binary is an user-space
-  application. If you need raw support for querying `cpuid`, consider using the
-  [`cupid`](https://crates.io/crates/cupid) crate.
+  application.
 
 * Linux/Android:
   * `arm{32, 64}`, `mips{32,64}{,el}`, `powerpc{32,64}{,le}`, `loongarch64`, `s390x`:

crates/std_detect/src/detect/cache.rs

@@ -121,65 +121,12 @@ impl Cache {
     }
 }
 
-cfg_if::cfg_if! {
-    if #[cfg(feature = "std_detect_env_override")] {
-        #[inline]
-        fn disable_features(disable: &[u8], value: &mut Initializer) {
-            if let Ok(disable) = core::str::from_utf8(disable) {
-                for v in disable.split(" ") {
-                    let _ = super::Feature::from_str(v).map(|v| value.unset(v as u32));
-                }
-            }
-        }
-
-        #[inline]
-        fn initialize(mut value: Initializer) -> Initializer {
-            use core::ffi::CStr;
-            const RUST_STD_DETECT_UNSTABLE: &CStr = c"RUST_STD_DETECT_UNSTABLE";
-            cfg_if::cfg_if! {
-                if #[cfg(windows)] {
-                    use alloc::vec;
-                    #[link(name = "kernel32")]
-                    unsafe extern "system" {
-                        fn GetEnvironmentVariableA(name: *const u8, buffer: *mut u8, size: u32) -> u32;
-                    }
-                    let len = unsafe { GetEnvironmentVariableA(RUST_STD_DETECT_UNSTABLE.as_ptr().cast::<u8>(), core::ptr::null_mut(), 0) };
-                    if len > 0 {
-                        // +1 to include the null terminator.
-                        let mut env = vec![0; len as usize + 1];
-                        let len = unsafe { GetEnvironmentVariableA(RUST_STD_DETECT_UNSTABLE.as_ptr().cast::<u8>(), env.as_mut_ptr(), len + 1) };
-                        if len > 0 {
-                            disable_features(&env[..len as usize], &mut value);
-                        }
-                    }
-                } else {
-                    let env = unsafe {
-                        libc::getenv(RUST_STD_DETECT_UNSTABLE.as_ptr())
-                    };
-                    if !env.is_null() {
-                        let len = unsafe { libc::strlen(env) };
-                        let env = unsafe { core::slice::from_raw_parts(env as *const u8, len) };
-                        disable_features(env, &mut value);
-                    }
-                }
-            }
-            do_initialize(value);
-            value
-        }
-    } else {
-        #[inline]
-        fn initialize(value: Initializer) -> Initializer {
-            do_initialize(value);
-            value
-        }
-    }
-}
-
 #[inline]
-fn do_initialize(value: Initializer) {
+fn initialize(value: Initializer) -> Initializer {
     CACHE[0].initialize((value.0) as usize & Cache::MASK);
     CACHE[1].initialize((value.0 >> Cache::CAPACITY) as usize & Cache::MASK);
     CACHE[2].initialize((value.0 >> (2 * Cache::CAPACITY)) as usize & Cache::MASK);
+    value
 }
 
 // We only have to detect features once, and it's fairly costly, so hint to LLVM
@@ -204,10 +151,6 @@ fn detect_and_initialize() -> Initializer {
 ///
 /// It uses the `Feature` variant to index into this variable as a bitset. If
 /// the bit is set, the feature is enabled, and otherwise it is disabled.
-///
-/// If the feature `std_detect_env_override` is enabled looks for the env
-/// variable `RUST_STD_DETECT_UNSTABLE` and uses its content to disable
-/// Features that would had been otherwise detected.
 #[inline]
 pub(crate) fn test(bit: u32) -> bool {
     let (relative_bit, idx) = if bit < Cache::CAPACITY {

crates/std_detect/src/detect/macros.rs

@@ -168,13 +168,6 @@ macro_rules! features {
                     Feature::_last => unreachable!(),
                 }
             }
-            #[cfg(feature = "std_detect_env_override")]
-            pub(crate) fn from_str(s: &str) -> Result<Feature, ()> {
-                match s {
-                    $($feature_lit => Ok(Feature::$feature),)*
-                    _ => Err(())
-                }
-            }
         }
 
         /// Each function performs run-time feature detection for a single

crates/std_detect/tests/x86-specific.rs

@@ -10,7 +10,6 @@
     movrs_target_feature
 )]
 
-extern crate cupid;
 #[macro_use]
 extern crate std_detect;
 
@@ -109,96 +108,6 @@ fn dump() {
     println!("amx-movrs: {:?}", is_x86_feature_detected!("amx-movrs"));
 }
 
-#[cfg(feature = "std_detect_env_override")]
-#[test]
-fn env_override_no_avx() {
-    if let Ok(disable) = std::env::var("RUST_STD_DETECT_UNSTABLE") {
-        let information = cupid::master().unwrap();
-        for d in disable.split(" ") {
-            match d {
-                "avx" => {
-                    if information.avx() {
-                        assert_ne!(is_x86_feature_detected!("avx"), information.avx())
-                    }
-                }
-                "avx2" => {
-                    if information.avx2() {
-                        assert_ne!(is_x86_feature_detected!("avx2"), information.avx2())
-                    }
-                }
-                _ => {}
-            }
-        }
-    }
-}
-
-#[test]
-fn compare_with_cupid() {
-    let information = cupid::master().unwrap();
-    assert_eq!(is_x86_feature_detected!("aes"), information.aesni());
-    assert_eq!(
-        is_x86_feature_detected!("pclmulqdq"),
-        information.pclmulqdq()
-    );
-    assert_eq!(is_x86_feature_detected!("rdrand"), information.rdrand());
-    assert_eq!(is_x86_feature_detected!("rdseed"), information.rdseed());
-    assert_eq!(is_x86_feature_detected!("tsc"), information.tsc());
-    assert_eq!(is_x86_feature_detected!("sse"), information.sse());
-    assert_eq!(is_x86_feature_detected!("sse2"), information.sse2());
-    assert_eq!(is_x86_feature_detected!("sse3"), information.sse3());
-    assert_eq!(is_x86_feature_detected!("ssse3"), information.ssse3());
-    assert_eq!(is_x86_feature_detected!("sse4.1"), information.sse4_1());
-    assert_eq!(is_x86_feature_detected!("sse4.2"), information.sse4_2());
-    assert_eq!(is_x86_feature_detected!("sse4a"), information.sse4a());
-    assert_eq!(is_x86_feature_detected!("sha"), information.sha());
-    assert_eq!(is_x86_feature_detected!("f16c"), information.f16c());
-    assert_eq!(is_x86_feature_detected!("avx"), information.avx());
-    assert_eq!(is_x86_feature_detected!("avx2"), information.avx2());
-    assert_eq!(is_x86_feature_detected!("avx512f"), information.avx512f());
-    assert_eq!(is_x86_feature_detected!("avx512cd"), information.avx512cd());
-    assert_eq!(is_x86_feature_detected!("avx512er"), information.avx512er());
-    assert_eq!(is_x86_feature_detected!("avx512pf"), information.avx512pf());
-    assert_eq!(is_x86_feature_detected!("avx512bw"), information.avx512bw());
-    assert_eq!(is_x86_feature_detected!("avx512dq"), information.avx512dq());
-    assert_eq!(is_x86_feature_detected!("avx512vl"), information.avx512vl());
-    assert_eq!(
-        is_x86_feature_detected!("avx512ifma"),
-        information.avx512_ifma()
-    );
-    assert_eq!(
-        is_x86_feature_detected!("avx512vbmi"),
-        information.avx512_vbmi()
-    );
-    assert_eq!(
-        is_x86_feature_detected!("avx512vpopcntdq"),
-        information.avx512_vpopcntdq()
-    );
-    assert_eq!(is_x86_feature_detected!("fma"), information.fma());
-    assert_eq!(is_x86_feature_detected!("bmi1"), information.bmi1());
-    assert_eq!(is_x86_feature_detected!("bmi2"), information.bmi2());
-    assert_eq!(is_x86_feature_detected!("popcnt"), information.popcnt());
-    assert_eq!(is_x86_feature_detected!("abm"), information.lzcnt());
-    assert_eq!(is_x86_feature_detected!("tbm"), information.tbm());
-    assert_eq!(is_x86_feature_detected!("lzcnt"), information.lzcnt());
-    assert_eq!(is_x86_feature_detected!("xsave"), information.xsave());
-    assert_eq!(is_x86_feature_detected!("xsaveopt"), information.xsaveopt());
-    assert_eq!(
-        is_x86_feature_detected!("xsavec"),
-        information.xsavec_and_xrstor()
-    );
-    assert_eq!(
-        is_x86_feature_detected!("xsaves"),
-        information.xsaves_xrstors_and_ia32_xss()
-    );
-    assert_eq!(
-        is_x86_feature_detected!("cmpxchg16b"),
-        information.cmpxchg16b(),
-    );
-    assert_eq!(is_x86_feature_detected!("adx"), information.adx(),);
-    assert_eq!(is_x86_feature_detected!("rtm"), information.rtm(),);
-    assert_eq!(is_x86_feature_detected!("movbe"), information.movbe(),);
-}
-
 #[test]
 #[allow(deprecated)]
 fn x86_deprecated() {