wasmtime-c-api: Add `wasmtime_store_gc` for GCing `externref`s

crates/c-api/include/wasmtime.h

@@ -299,6 +299,17 @@ WASM_API_EXTERN own wasmtime_error_t* wasmtime_wat2wasm(
     own wasm_byte_vec_t *ret
 );
 
+/**
+ * \brief Perform garbage collection within the given store.
+ *
+ * Garbage collects `externref`s that are used within this store. Any
+ * `externref`s that are discovered to be unreachable by other code or objects
+ * will have their finalizers run.
+ *
+ * The `store` argument must not be NULL.
+ */
+WASM_API_EXTERN void wasmtime_store_gc(wasm_store_t* store);
+
 /**
  * \typedef wasmtime_linker_t
  * \brief Convenience alias for #wasmtime_linker_t

crates/c-api/src/store.rs

@@ -17,6 +17,11 @@ pub extern "C" fn wasm_store_new(engine: &wasm_engine_t) -> Box<wasm_store_t> {
     })
 }
 
+#[no_mangle]
+pub extern "C" fn wasmtime_store_gc(store: &wasm_store_t) {
+    store.store.gc();
+}
+
 #[repr(C)]
 pub struct wasmtime_interrupt_handle_t {
     handle: InterruptHandle,