fix: issue 529 (#535)

Fix #529

src/lock_file/python.rs

@@ -219,9 +219,16 @@ fn project_platforms(platform: Platform, system_requirements: &SystemRequirement
             _ => unreachable!("not windows"),
         }
     } else if platform.is_linux() {
-        let max_glibc_version = match &system_requirements.libc {
-            Some(LibCSystemRequirement::GlibC(v)) => v.clone(),
-            Some(LibCSystemRequirement::OtherFamily(_)) => return Vec::new(),
+        let max_glibc_version = match system_requirements
+            .libc
+            .as_ref()
+            .map(LibCSystemRequirement::family_and_version)
+        {
+            Some((family, version)) if family.eq_ignore_ascii_case("glibc") => version.clone(),
+            Some(_) => {
+                // Another libc family is being target.
+                return Vec::new();
+            }
             None => default_glibc_version(),
         };
         linux_platform_tags(platform, &max_glibc_version)

src/project/manifest.rs

@@ -378,6 +378,18 @@ pub enum LibCSystemRequirement {
     OtherFamily(LibCFamilyAndVersion),
 }
 
+impl LibCSystemRequirement {
+    /// Returns the family and version of this libc requirement.
+    pub fn family_and_version(&self) -> (&str, &Version) {
+        match self {
+            LibCSystemRequirement::GlibC(version) => ("glibc", version),
+            LibCSystemRequirement::OtherFamily(LibCFamilyAndVersion { family, version: v }) => {
+                (family.as_deref().unwrap_or("glibc"), v)
+            }
+        }
+    }
+}
+
 #[serde_as]
 #[derive(Debug, Clone, Deserialize)]
 #[serde(deny_unknown_fields)]