diff --git a/src/php/ext/grpc/server.c b/src/php/ext/grpc/server.c
index 55a61e2b448..9ac5d2a3c39 100644
--- a/src/php/ext/grpc/server.c
+++ b/src/php/ext/grpc/server.c
@@ -50,6 +50,7 @@
 #include <grpc/grpc.h>
 #include <grpc/grpc_security.h>
 #include <grpc/slice.h>
+#include <grpc/support/alloc.h>
 
 #include "completion_queue.h"
 #include "server.h"