1# SPDX-License-Identifier: FSFAP
2#
3# ===========================================================================
4#    https://www.gnu.org/software/autoconf-archive/ax_check_link_flag.html
5# ===========================================================================
6#
7# SYNOPSIS
8#
9#   AX_CHECK_LINK_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS], [INPUT])
10#
11# DESCRIPTION
12#
13#   Check whether the given FLAG works with the linker or gives an error.
14#   (Warnings, however, are ignored)
15#
16#   ACTION-SUCCESS/ACTION-FAILURE are shell commands to execute on
17#   success/failure.
18#
19#   If EXTRA-FLAGS is defined, it is added to the linker's default flags
20#   when the check is done.  The check is thus made with the flags: "LDFLAGS
21#   EXTRA-FLAGS FLAG".  This can for example be used to force the linker to
22#   issue an error when a bad flag is given.
23#
24#   INPUT gives an alternative input source to AC_LINK_IFELSE.
25#
26#   NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. Please keep this
27#   macro in sync with AX_CHECK_{PREPROC,COMPILE}_FLAG.
28#
29# LICENSE
30#
31#   Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
32#   Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
33#
34#   Copying and distribution of this file, with or without modification, are
35#   permitted in any medium without royalty provided the copyright notice
36#   and this notice are preserved.  This file is offered as-is, without any
37#   warranty.
38
39#serial 6
40
41AC_DEFUN([AX_CHECK_LINK_FLAG],
42[AC_PREREQ(2.64)dnl for _AC_LANG_PREFIX and AS_VAR_IF
43AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_ldflags_$4_$1])dnl
44AC_CACHE_CHECK([whether the linker accepts $1], CACHEVAR, [
45  ax_check_save_flags=$LDFLAGS
46  LDFLAGS="$LDFLAGS $4 $1"
47  AC_LINK_IFELSE([m4_default([$5],[AC_LANG_PROGRAM()])],
48    [AS_VAR_SET(CACHEVAR,[yes])],
49    [AS_VAR_SET(CACHEVAR,[no])])
50  LDFLAGS=$ax_check_save_flags])
51AS_VAR_IF(CACHEVAR,yes,
52  [m4_default([$2], :)],
53  [m4_default([$3], :)])
54AS_VAR_POPDEF([CACHEVAR])dnl
55])dnl AX_CHECK_LINK_FLAGS
56