1# warnings.m4 serial 7
2dnl Copyright (C) 2008-2012 Free Software Foundation, Inc.
3dnl This file is free software; the Free Software Foundation
4dnl gives unlimited permission to copy and/or distribute it,
5dnl with or without modifications, as long as this notice is preserved.
6
7dnl From Simon Josefsson
8
9# gl_AS_VAR_APPEND(VAR, VALUE)
10# ----------------------------
11# Provide the functionality of AS_VAR_APPEND if Autoconf does not have it.
12m4_ifdef([AS_VAR_APPEND],
13[m4_copy([AS_VAR_APPEND], [gl_AS_VAR_APPEND])],
14[m4_define([gl_AS_VAR_APPEND],
15[AS_VAR_SET([$1], [AS_VAR_GET([$1])$2])])])
16
17
18# gl_COMPILER_OPTION_IF(OPTION, [IF-SUPPORTED], [IF-NOT-SUPPORTED],
19#                       [PROGRAM = AC_LANG_PROGRAM()])
20# -----------------------------------------------------------------
21# Check if the compiler supports OPTION when compiling PROGRAM.
22#
23# FIXME: gl_Warn must be used unquoted until we can assume Autoconf
24# 2.64 or newer.
25AC_DEFUN([gl_COMPILER_OPTION_IF],
26[AS_VAR_PUSHDEF([gl_Warn], [gl_cv_warn_[]_AC_LANG_ABBREV[]_$1])dnl
27AS_VAR_PUSHDEF([gl_Flags], [_AC_LANG_PREFIX[]FLAGS])dnl
28AC_CACHE_CHECK([whether _AC_LANG compiler handles $1], m4_defn([gl_Warn]), [
29  gl_save_compiler_FLAGS="$gl_Flags"
30  gl_AS_VAR_APPEND(m4_defn([gl_Flags]), [" $1"])
31  AC_COMPILE_IFELSE([m4_default([$4], [AC_LANG_PROGRAM([])])],
32                    [AS_VAR_SET(gl_Warn, [yes])],
33                    [AS_VAR_SET(gl_Warn, [no])])
34  gl_Flags="$gl_save_compiler_FLAGS"
35])
36AS_VAR_IF(gl_Warn, [yes], [$2], [$3])
37AS_VAR_POPDEF([gl_Flags])dnl
38AS_VAR_POPDEF([gl_Warn])dnl
39])
40
41
42# gl_WARN_ADD(OPTION, [VARIABLE = WARN_CFLAGS],
43#             [PROGRAM = AC_LANG_PROGRAM()])
44# ---------------------------------------------
45# Adds parameter to WARN_CFLAGS if the compiler supports it when
46# compiling PROGRAM.  For example, gl_WARN_ADD([-Wparentheses]).
47#
48# If VARIABLE is a variable name, AC_SUBST it.
49AC_DEFUN([gl_WARN_ADD],
50[gl_COMPILER_OPTION_IF([$1],
51  [gl_AS_VAR_APPEND(m4_if([$2], [], [[WARN_CFLAGS]], [[$2]]), [" $1"])],
52  [],
53  [$3])
54m4_ifval([$2],
55         [AS_LITERAL_IF([$2], [AC_SUBST([$2])])],
56         [AC_SUBST([WARN_CFLAGS])])dnl
57])
58
59# Local Variables:
60# mode: autoconf
61# End:
62