# =========================================================================== # https://www.gnu.org/software/autoconf-archive/ax_append_flag.html # =========================================================================== # # SYNOPSIS # # AX_APPEND_FLAG(FLAG, [FLAGS-VARIABLE]) # # DESCRIPTION # # FLAG is appended to the FLAGS-VARIABLE shell variable, with a space # added in between. # # If FLAGS-VARIABLE is not specified, the current language's flags (e.g. # CFLAGS) is used. FLAGS-VARIABLE is not changed if it already contains # FLAG. If FLAGS-VARIABLE is unset in the shell, it is set to exactly # FLAG. # # NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. # # LICENSE # # Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de> # Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com> # # Copying and distribution of this file, with or without modification, are # permitted in any medium without royalty provided the copyright notice # and this notice are preserved. This file is offered as-is, without any # warranty. #serial 8 AC_DEFUN([AX_APPEND_FLAG], [dnl AC_PREREQ(2.64)dnl for _AC_LANG_PREFIX and AS_VAR_SET_IF AS_VAR_PUSHDEF([FLAGS], [m4_default($2,_AC_LANG_PREFIX[FLAGS])]) AS_VAR_SET_IF(FLAGS,[ AS_CASE([" AS_VAR_GET(FLAGS) "], [*" $1 "*], [AC_RUN_LOG([: FLAGS already contains $1])], [ AS_VAR_APPEND(FLAGS,[" $1"]) AC_RUN_LOG([: FLAGS="$FLAGS"]) ]) ], [ AS_VAR_SET(FLAGS,[$1]) AC_RUN_LOG([: FLAGS="$FLAGS"]) ]) AS_VAR_POPDEF([FLAGS])dnl ])dnl AX_APPEND_FLAG