Provide opt-out feature=from_source to use serde_derive source

precompiled/serde_derive/Cargo.toml

@@ -21,7 +21,7 @@ deserialize_in_place = []
 [lib]
 proc-macro = true
 
-[target.'cfg(not(all(serde_derive_build = "precompiled", target_arch = "x86_64", target_os = "linux", target_env = "gnu")))'.dependencies]
+[target.'cfg(serde_derive_build = "source")'.dependencies]
 proc-macro2 = "1"
 quote = "1"
 syn = "2.0.28"

precompiled/serde_derive/build.rs

@@ -0,0 +1,21 @@
+fn is_target_precompiled(target: &str) -> bool {
+    target == "x86_64-unknown-linux-gnu"
+}
+
+fn main() {
+    // Alternatively use platforms crate etc. for Types
+    let target = match std::env::var("TARGET") {
+        Ok(target) => target,
+        _ => "".to_string(), // TARGET should be required ?
+    };
+    println!("cargo:warning=\"{target}\"");
+    // This is required to simplify gating
+    let derive_build = match std::env::var("CARGO_CFG_SERDE_DERIVE_BUILD").as_deref() {
+        Ok("source") => "source",
+        _ => match is_target_precompiled(&target) {
+            true => "precompiled",
+            false => "source",
+        },
+    };
+    println!("cargo:rustc-cfg=serde_derive_build=\"{derive_build}\"");
+}

precompiled/serde_derive/src/lib.rs

@@ -15,18 +15,8 @@
 
 #![doc(html_root_url = "https://docs.rs/serde_derive/1.0.183")]
 
-#[cfg(all(
-    serde_derive_build = "source",
-    target_arch = "x86_64",
-    target_os = "linux",
-    target_env = "gnu"
-))]
+#[cfg(serde_derive_build = "source")]
 include!("lib_from_source.rs");
 
-#[cfg(all(
-    not(serde_derive_build = "source"),
-    target_arch = "x86_64",
-    target_os = "linux",
-    target_env = "gnu"
-))]
+#[cfg(not(serde_derive_build = "source"))]
 include!("lib_precompiled.rs");