diff --git a/tools/mksyscall.c b/tools/mksyscall.c
index 07ee2261c6..b2616c09d9 100644
--- a/tools/mksyscall.c
+++ b/tools/mksyscall.c
@@ -240,7 +240,11 @@ static void generate_proxy(int nparms)
       nformal = nparms;
     }
 
-  fprintf(stream, "#include <%s>\n", g_parm[HEADER_INDEX]);
+  if (g_parm[HEADER_INDEX] && strlen(g_parm[HEADER_INDEX]) > 0)
+    {
+      fprintf(stream, "#include <%s>\n", g_parm[HEADER_INDEX]);
+    }
+
   fprintf(stream, "#include <syscall.h>\n\n");
 
   if (g_parm[COND_INDEX][0] != '\0')
@@ -420,7 +424,13 @@ static void generate_stub(int nparms)
   fprintf(stream, "/* Auto-generated %s stub file -- do not edit */\n\n", g_parm[0]);
   fprintf(stream, "#include <nuttx/config.h>\n");
   fprintf(stream, "#include <stdint.h>\n");
-  fprintf(stream, "#include <%s>\n\n", g_parm[HEADER_INDEX]);
+
+  if (g_parm[HEADER_INDEX] && strlen(g_parm[HEADER_INDEX]) > 0)
+    {
+      fprintf(stream, "#include <%s>\n", g_parm[HEADER_INDEX]);
+    }
+
+  putc('\n', stream);
 
   if (g_parm[COND_INDEX][0] != '\0')
     {