diff --git a/reader.cpp b/reader.cpp
index 8a814968f..5882e727f 100644
--- a/reader.cpp
+++ b/reader.cpp
@@ -726,7 +726,8 @@ static void exec_prompt()
         if (! data->left_prompt.empty())
         {
             wcstring_list_t prompt_list;
-            exec_subshell(data->left_prompt, prompt_list);
+            // status is ignored
+            __mark_as_unused int status = exec_subshell(data->left_prompt, prompt_list);
             for (size_t i = 0; i < prompt_list.size(); i++)
             {
                 if (i > 0) data->left_prompt_buff += L'\n';
@@ -737,7 +738,8 @@ static void exec_prompt()
         if (! data->right_prompt.empty())
         {
             wcstring_list_t prompt_list;
-            exec_subshell(data->right_prompt, prompt_list);
+            // status is ignored
+            __mark_as_unused int status = exec_subshell(data->right_prompt, prompt_list);
             for (size_t i = 0; i < prompt_list.size(); i++)
             {
                 // Right prompt does not support multiple lines, so just concatenate all of them