diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 6a84138..b944e69 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -9,8 +9,8 @@ on:
       - '*'
 
 env:
-  CFLAGS: -Werror
-  CXXFLAGS: -Werror
+  CFLAGS: -Werror -O2
+  CXXFLAGS: -Werror -O2
   DEBIAN_FRONTEND: noninteractive
 
 jobs:
diff --git a/src/ipc/ipc_proc.h b/src/ipc/ipc_proc.h
index d5eae43..245f621 100644
--- a/src/ipc/ipc_proc.h
+++ b/src/ipc/ipc_proc.h
@@ -54,7 +54,7 @@ ipc_proc_t* ipc_proc_start(const char* const args[])
    #endif
    */
 
-    ipc_proc_t* const proc = (ipc_proc_t*)calloc(1, sizeof(ipc_proc_t));
+    ipc_proc_t* volatile const proc = (ipc_proc_t*)calloc(1, sizeof(ipc_proc_t));
     if (proc == NULL)
     {
         fprintf(stderr, "[ipc] ipc_proc_start failed: out of memory\n");
diff --git a/src/ui-client.c b/src/ui-client.c
index 2621556..9d16073 100644
--- a/src/ui-client.c
+++ b/src/ui-client.c
@@ -177,8 +177,6 @@ static void lv2ui_uris_cleanup(LV2UI_URIs* const uiuris)
 {
     for (uint32_t i = 0; i < uiuris->max_urid; ++i)
         free(uiuris->uris[i]);
-
-    free(uiuris);
 }
 
 static void lv2ui_write_function(LV2UI_Controller controller,