diff --git a/m4/cares-compilers.m4 b/m4/cares-compilers.m4
index 72e9db2..0609abf 100644
--- a/m4/cares-compilers.m4
+++ b/m4/cares-compilers.m4
@@ -16,7 +16,7 @@
 #***************************************************************************
 
 # File version for 'aclocal' use. Keep it a single number.
-# serial 21
+# serial 22
 
 
 dnl CARES_CHECK_COMPILER
@@ -784,8 +784,11 @@ AC_DEFUN([CARES_SET_COMPILER_WARNING_OPTS], [
       LCC)
         #
         if test "$want_warnings" = "yes"; then
-          dnl Highest warning level is double -A
-          tmp_CFLAGS="$tmp_CFLAGS -A -A"
+          dnl Highest warning level is double -A, next is single -A.
+          dnl Due to the big number of warnings this triggers on third
+          dnl party header files it is impratical for to activate this
+          dnl warning level here. If you want them define it in CFLAGS.
+          tmp_CFLAGS="$tmp_CFLAGS -A"
         fi
         ;;
         #