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Author: timsaucer

datafusion/ffi/src/config/extension_options.rs

@@ -109,10 +109,13 @@ unsafe extern "C" fn entries_fn_wrapper(
 }
 
 unsafe extern "C" fn release_fn_wrapper(options: &mut FFI_ExtensionOptions) {
-    let private_data = unsafe {
-        Box::from_raw(options.private_data as *mut ExtensionOptionsPrivateData)
-    };
-    drop(private_data);
+    unsafe {
+        debug_assert!(!options.private_data.is_null());
+        let private_data =
+            Box::from_raw(options.private_data as *mut ExtensionOptionsPrivateData);
+        drop(private_data);
+        options.private_data = std::ptr::null_mut();
+    }
 }
 
 impl Default for FFI_ExtensionOptions {

datafusion/ffi/src/session/config.rs

@@ -37,8 +37,7 @@ use datafusion_execution::config::SessionConfig;
 #[repr(C)]
 #[derive(Debug, StableAbi)]
 pub struct FFI_SessionConfig {
-    /// Return a hash map from key to value of the config options represented
-    /// by string values.
+    /// FFI stable configuration options.
     pub config_options: FFI_ConfigOptions,
 
     /// Used to create a clone on the provider of the execution plan. This should