diff --git a/exec.cpp b/exec.cpp
index 33e2daac8..7fc94b0c7 100644
--- a/exec.cpp
+++ b/exec.cpp
@@ -1519,7 +1519,7 @@ int exec_subshell(const wcstring &cmd, std::vector<wcstring> &outputs, bool appl
     return exec_subshell_internal(cmd, &outputs, apply_exit_status);
 }
 
-__warn_unused int exec_subshell(const wcstring &cmd, bool apply_exit_status)
+int exec_subshell(const wcstring &cmd, bool apply_exit_status)
 {
     ASSERT_IS_MAIN_THREAD();
     return exec_subshell_internal(cmd, NULL, apply_exit_status);
diff --git a/exec.h b/exec.h
index 9a9d2dc53..edae1e557 100644
--- a/exec.h
+++ b/exec.h
@@ -54,8 +54,8 @@ void exec(parser_t &parser, job_t *j);
 
   \return the status of the last job to exit, or -1 if en error was encountered.
 */
-__warn_unused int exec_subshell(const wcstring &cmd, std::vector<wcstring> &outputs, bool preserve_exit_status);
-__warn_unused int exec_subshell(const wcstring &cmd, bool preserve_exit_status);
+int exec_subshell(const wcstring &cmd, std::vector<wcstring> &outputs, bool preserve_exit_status);
+int exec_subshell(const wcstring &cmd, bool preserve_exit_status);
 
 
 /**
diff --git a/reader.cpp b/reader.cpp
index 99a9c2512..92d0aa521 100644
--- a/reader.cpp
+++ b/reader.cpp
@@ -770,10 +770,8 @@ static void exec_prompt()
         if (! data->left_prompt.empty())
         {
             wcstring_list_t prompt_list;
-            if (exec_subshell(data->left_prompt, prompt_list, apply_exit_status))
-            {
-                // returned status value is ignored
-            }
+            // ignore return status
+            exec_subshell(data->left_prompt, prompt_list, apply_exit_status);
             for (size_t i = 0; i < prompt_list.size(); i++)
             {
                 if (i > 0) data->left_prompt_buff += L'\n';
@@ -785,10 +783,7 @@ static void exec_prompt()
         {
             wcstring_list_t prompt_list;
             // status is ignored
-            if (exec_subshell(data->right_prompt, prompt_list, apply_exit_status))
-            {
-                // returned status value is ignored
-            }
+            exec_subshell(data->right_prompt, prompt_list, apply_exit_status);
             for (size_t i = 0; i < prompt_list.size(); i++)
             {
                 // Right prompt does not support multiple lines, so just concatenate all of them