diff --git a/libs/libc/stdio/lib_libvsprintf.c b/libs/libc/stdio/lib_libvsprintf.c
index c331d815692a1..3df402d7e98f6 100644
--- a/libs/libc/stdio/lib_libvsprintf.c
+++ b/libs/libc/stdio/lib_libvsprintf.c
@@ -1018,7 +1018,11 @@ static int vsprintf_internal(FAR struct lib_outstream_s *stream,
           flags &= ~(FL_NEGATIVE | FL_ALT);
           if (x < 0)
             {
-              x = -x;
+#ifndef CONFIG_HAVE_LONG_LONG
+              x = -(unsigned long)x;
+#else
+              x = -(unsigned long long)x;
+#endif
               flags |= FL_NEGATIVE;
             }