diff --git a/build.rs b/build.rs
index 1d3c4ac..04ff4a0 100644
--- a/build.rs
+++ b/build.rs
@@ -22,14 +22,14 @@ fn main() {
 
     // BTreeMap::get_key_value
     // https://blog.rust-lang.org/2019/12/19/Rust-1.40.0.html#additions-to-the-standard-library
-    if minor >= 40 {
-        println!("cargo:rustc-cfg=btreemap_get_key_value");
+    if minor < 40 {
+        println!("cargo:rustc-cfg=no_btreemap_get_key_value");
     }
 
     // BTreeMap::remove_entry
     // https://blog.rust-lang.org/2020/07/16/Rust-1.45.0.html#library-changes
-    if minor >= 45 {
-        println!("cargo:rustc-cfg=btreemap_remove_entry");
+    if minor < 45 {
+        println!("cargo:rustc-cfg=no_btreemap_remove_entry");
     }
 }
 
diff --git a/src/map.rs b/src/map.rs
index c64534f..5da17cf 100644
--- a/src/map.rs
+++ b/src/map.rs
@@ -132,16 +132,16 @@ impl Map<String, Value> {
         String: Borrow<Q>,
         Q: ?Sized + Ord + Eq + Hash,
     {
-        #[cfg(any(feature = "preserve_order", btreemap_remove_entry))]
+        #[cfg(any(feature = "preserve_order", not(no_btreemap_remove_entry)))]
         return self.map.remove_entry(key);
-        #[cfg(all(btreemap_get_key_value, not(any(feature = "preserve_order", btreemap_remove_entry))))]
+        #[cfg(all(not(no_btreemap_get_key_value), not(any(feature = "preserve_order", not(no_btreemap_remove_entry)))))]
         {
             let (key, _value) = self.map.get_key_value(key)?;
             let key = key.clone();
             let value = self.map.remove::<String>(&key)?;
             Some((key, value))
         }
-        #[cfg(not(any(feature = "preserve_order", btreemap_remove_entry, btreemap_get_key_value)))]
+        #[cfg(not(any(feature = "preserve_order", not(no_btreemap_remove_entry), not(no_btreemap_get_key_value))))]
         {
             use std::ops::{Bound, RangeBounds};