diff --git a/src/job.c b/src/job.c
index 34ef9b80..f7f97010 100644
--- a/src/job.c
+++ b/src/job.c
@@ -362,7 +362,7 @@ create_batch_file (char const *base, int unixy, int *fd)
   *fd = -1;
   if (error_string == NULL)
     error_string = _("Cannot create a temporary file");
-  O (fatal, NILF, error_string);
+  OS (fatal, NILF, "%s", error_string);
 
   /* not reached */
   return NULL;
diff --git a/src/main.c b/src/main.c
index 9ec8f20a..26d6ba34 100644
--- a/src/main.c
+++ b/src/main.c
@@ -955,7 +955,7 @@ handle_runtime_exceptions (struct _EXCEPTION_POINTERS *exinfo)
       sprintf (errmsg,
                _("%s: Interrupt/Exception caught (code = 0x%lx, addr = 0x%p)\n"),
                prg, exrec->ExceptionCode, exrec->ExceptionAddress);
-      fprintf (stderr, errmsg);
+      fputs (errmsg, stderr);
       exit (255);
     }
 
@@ -994,7 +994,7 @@ handle_runtime_exceptions (struct _EXCEPTION_POINTERS *exinfo)
 #endif
 
   /* Write the error to stderr too */
-  fprintf (stderr, errmsg);
+  fputs (errmsg, stderr);
 
 #ifdef DEBUG
   return EXCEPTION_CONTINUE_SEARCH;
diff --git a/src/w32/subproc/w32err.c b/src/w32/subproc/w32err.c
index e947a5b2..42ca595c 100644
--- a/src/w32/subproc/w32err.c
+++ b/src/w32/subproc/w32err.c
@@ -56,7 +56,7 @@ map_windows32_error_to_string (DWORD ercode) {
    *  Special code for winsock error handling.
    */
   if (ercode > WSABASEERR) {
-    O (fatal, NILF, szMessageBuffer);
+    OS (fatal, NILF, "%s", szMessageBuffer);
   }
 
   /*