uv python install: Detect hard-float support

Cargo.toml

@@ -120,6 +120,7 @@ path-slash = { version = "0.2.1" }
 pathdiff = { version = "0.2.1" }
 petgraph = { version = "0.6.5" }
 platform-info = { version = "2.0.3" }
+procfs = { version = "0.16.0" }
 proc-macro2 = { version = "1.0.86" }
 pubgrub = { git = "https://github.com/astral-sh/pubgrub", rev = "388685a8711092971930986644cfed152d1a1f6c" }
 pyo3 = { version = "0.21.2" }

crates/uv-python/Cargo.toml

@@ -36,6 +36,7 @@ futures = { workspace = true }
 goblin = { workspace = true }
 itertools = { workspace = true }
 owo-colors = { workspace = true }
+procfs = { workspace = true }
 regex = { workspace = true }
 reqwest = { workspace = true }
 reqwest-middleware = { workspace = true }

crates/uv-python/src/cpuinfo.rs

@@ -0,0 +1,16 @@
+//! Fetches CPU information.
+
+use anyhow::Error;
+use procfs::{CpuInfo, Current};
+
+pub(crate) fn detect_hardware_floating_point_support() -> Result<bool, Error> {
+    let cpu_info = CpuInfo::current()?;
+    for num in 0..cpu_info.num_cores() {
+        if let Some(flags) = cpu_info.flags(num) {
+            if flags.contains(&"vfp") {
+                return Ok(true);
+            }
+        }
+    }
+    Ok(false)
+}

crates/uv-python/src/lib.rs

@@ -18,6 +18,7 @@ pub use crate::version_files::{
 };
 pub use crate::virtualenv::{Error as VirtualEnvError, PyVenvConfiguration, VirtualEnvironment};
 
+mod cpuinfo;
 mod discovery;
 pub mod downloads;
 mod environment;

crates/uv-python/src/platform.rs

@@ -1,3 +1,4 @@
+use crate::cpuinfo::detect_hardware_floating_point_support;
 use crate::libc::{detect_linux_libc, LibcDetectionError, LibcVersion};
 use std::fmt::Display;
 use std::ops::Deref;
@@ -30,7 +31,15 @@ impl Libc {
     pub(crate) fn from_env() -> Result<Self, LibcDetectionError> {
         match std::env::consts::OS {
             "linux" => Ok(Self::Some(match detect_linux_libc()? {
-                LibcVersion::Manylinux { .. } => target_lexicon::Environment::Gnu,
+                LibcVersion::Manylinux { .. } => match std::env::consts::ARCH {
+                    // download-metadata.json only includes armv7.
+                    "arm" | "armv7" => match detect_hardware_floating_point_support() {
+                        Ok(true) => target_lexicon::Environment::Gnueabihf,
+                        Ok(false) => target_lexicon::Environment::Gnueabi,
+                        Err(_) => target_lexicon::Environment::Gnu,
+                    },
+                    _ => target_lexicon::Environment::Gnu,
+                },
                 LibcVersion::Musllinux { .. } => target_lexicon::Environment::Musl,
             })),
             "windows" | "macos" => Ok(Self::None),