m4/gnulib-common.m4

   1 # gnulib-common.m4 serial 28
   2 dnl Copyright (C) 2007-2011 Free Software Foundation, Inc.
   3 dnl This file is free software; the Free Software Foundation
   4 dnl gives unlimited permission to copy and/or distribute it,
   5 dnl with or without modifications, as long as this notice is preserved.
   6
   7 # gl_COMMON
   8 # is expanded unconditionally through gnulib-tool magic.
   9 AC_DEFUN([gl_COMMON], [
  10   dnl Use AC_REQUIRE here, so that the code is expanded once only.
  11   AC_REQUIRE([gl_00GNULIB])
  12   AC_REQUIRE([gl_COMMON_BODY])
  13 ])
  14 AC_DEFUN([gl_COMMON_BODY], [
  15   AH_VERBATIM([_Noreturn],
  16 [/* The _Noreturn keyword of draft C1X.  */
  17 #ifndef _Noreturn
  18 # if (3 <= __GNUC__ || (__GNUC__ == 2 && 8 <= __GNUC_MINOR__) \
  19       || 0x5110 <= __SUNPRO_C)
  20 #  define _Noreturn __attribute__ ((__noreturn__))
  21 # elif 1200 <= _MSC_VER
  22 #  define _Noreturn __declspec (noreturn)
  23 # else
  24 #  define _Noreturn
  25 # endif
  26 #endif
  27 ])
  28   AH_VERBATIM([isoc99_inline],
  29 [/* Work around a bug in Apple GCC 4.0.1 build 5465: In C99 mode, it supports
  30    the ISO C 99 semantics of 'extern inline' (unlike the GNU C semantics of
  31    earlier versions), but does not display it by setting __GNUC_STDC_INLINE__.
  32    __APPLE__ && __MACH__ test for MacOS X.
  33    __APPLE_CC__ tests for the Apple compiler and its version.
  34    __STDC_VERSION__ tests for the C99 mode.  */
  35 #if defined __APPLE__ && defined __MACH__ && __APPLE_CC__ >= 5465 && !defined __cplusplus && __STDC_VERSION__ >= 199901L && !defined __GNUC_STDC_INLINE__
  36 # define __GNUC_STDC_INLINE__ 1
  37 #endif])
  38   AH_VERBATIM([unused_parameter],
  39 [/* Define as a marker that can be attached to declarations that might not
  40     be used.  This helps to reduce warnings, such as from
  41     GCC -Wunused-parameter.  */
  42 #if __GNUC__ >= 3 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 7)
  43 # define _GL_UNUSED __attribute__ ((__unused__))
  44 #else
  45 # define _GL_UNUSED
  46 #endif
  47 /* The name _UNUSED_PARAMETER_ is an earlier spelling, although the name
  48    is a misnomer outside of parameter lists.  */
  49 #define _UNUSED_PARAMETER_ _GL_UNUSED
  50
  51 /* The __pure__ attribute was added in gcc 2.96.  */
  52 #if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96)
  53 # define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__))
  54 #else
  55 # define _GL_ATTRIBUTE_PURE /* empty */
  56 #endif
  57
  58 /* The __const__ attribute was added in gcc 2.95.  */
  59 #if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 95)
  60 # define _GL_ATTRIBUTE_CONST __attribute__ ((__const__))
  61 #else
  62 # define _GL_ATTRIBUTE_CONST /* empty */
  63 #endif
  64 ])
  65   dnl Preparation for running test programs:
  66   dnl Tell glibc to write diagnostics from -D_FORTIFY_SOURCE=2 to stderr, not
  67   dnl to /dev/tty, so they can be redirected to log files.  Such diagnostics
  68   dnl arise e.g., in the macros gl_PRINTF_DIRECTIVE_N, gl_SNPRINTF_DIRECTIVE_N.
  69   LIBC_FATAL_STDERR_=1
  70   export LIBC_FATAL_STDERR_
  71 ])
  72
  73 # gl_MODULE_INDICATOR_CONDITION
  74 # expands to a C preprocessor expression that evaluates to 1 or 0, depending
  75 # whether a gnulib module that has been requested shall be considered present
  76 # or not.
  77 m4_define([gl_MODULE_INDICATOR_CONDITION], [1])
  78
  79 # gl_MODULE_INDICATOR_SET_VARIABLE([modulename])
  80 # sets the shell variable that indicates the presence of the given module to
  81 # a C preprocessor expression that will evaluate to 1.
  82 AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE],
  83 [
  84   gl_MODULE_INDICATOR_SET_VARIABLE_AUX(
  85     [GNULIB_[]m4_translit([[$1]],
  86                           [abcdefghijklmnopqrstuvwxyz./-],
  87                           [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])],
  88     [gl_MODULE_INDICATOR_CONDITION])
  89 ])
  90
  91 # gl_MODULE_INDICATOR_SET_VARIABLE_AUX([variable])
  92 # modifies the shell variable to include the gl_MODULE_INDICATOR_CONDITION.
  93 # The shell variable's value is a C preprocessor expression that evaluates
  94 # to 0 or 1.
  95 AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE_AUX],
  96 [
  97   m4_if(m4_defn([gl_MODULE_INDICATOR_CONDITION]), [1],
  98     [
  99      dnl Simplify the expression VALUE || 1 to 1.
 100      $1=1
 101     ],
 102     [gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR([$1],
 103                                              [gl_MODULE_INDICATOR_CONDITION])])
 104 ])
 105
 106 # gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR([variable], [condition])
 107 # modifies the shell variable to include the given condition.  The shell
 108 # variable's value is a C preprocessor expression that evaluates to 0 or 1.
 109 AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR],
 110 [
 111   dnl Simplify the expression 1 || CONDITION to 1.
 112   if test "$[]$1" != 1; then
 113     dnl Simplify the expression 0 || CONDITION to CONDITION.
 114     if test "$[]$1" = 0; then
 115       $1=$2
 116     else
 117       $1="($[]$1 || $2)"
 118     fi
 119   fi
 120 ])
 121
 122 # gl_MODULE_INDICATOR([modulename])
 123 # defines a C macro indicating the presence of the given module
 124 # in a location where it can be used.
 125 #                                             |  Value  |   Value   |
 126 #                                             | in lib/ | in tests/ |
 127 # --------------------------------------------+---------+-----------+
 128 # Module present among main modules:          |    1    |     1     |
 129 # --------------------------------------------+---------+-----------+
 130 # Module present among tests-related modules: |    0    |     1     |
 131 # --------------------------------------------+---------+-----------+
 132 # Module not present at all:                  |    0    |     0     |
 133 # --------------------------------------------+---------+-----------+
 134 AC_DEFUN([gl_MODULE_INDICATOR],
 135 [
 136   AC_DEFINE_UNQUOTED([GNULIB_]m4_translit([[$1]],
 137       [abcdefghijklmnopqrstuvwxyz./-],
 138       [ABCDEFGHIJKLMNOPQRSTUVWXYZ___]),
 139     [gl_MODULE_INDICATOR_CONDITION],
 140     [Define to a C preprocessor expression that evaluates to 1 or 0,
 141      depending whether the gnulib module $1 shall be considered present.])
 142 ])
 143
 144 # gl_MODULE_INDICATOR_FOR_TESTS([modulename])
 145 # defines a C macro indicating the presence of the given module
 146 # in lib or tests. This is useful to determine whether the module
 147 # should be tested.
 148 #                                             |  Value  |   Value   |
 149 #                                             | in lib/ | in tests/ |
 150 # --------------------------------------------+---------+-----------+
 151 # Module present among main modules:          |    1    |     1     |
 152 # --------------------------------------------+---------+-----------+
 153 # Module present among tests-related modules: |    1    |     1     |
 154 # --------------------------------------------+---------+-----------+
 155 # Module not present at all:                  |    0    |     0     |
 156 # --------------------------------------------+---------+-----------+
 157 AC_DEFUN([gl_MODULE_INDICATOR_FOR_TESTS],
 158 [
 159   AC_DEFINE([GNULIB_TEST_]m4_translit([[$1]],
 160       [abcdefghijklmnopqrstuvwxyz./-],
 161       [ABCDEFGHIJKLMNOPQRSTUVWXYZ___]), [1],
 162     [Define to 1 when the gnulib module $1 should be tested.])
 163 ])
 164
 165 # gl_ASSERT_NO_GNULIB_POSIXCHECK
 166 # asserts that there will never be a need to #define GNULIB_POSIXCHECK.
 167 # and thereby enables an optimization of configure and config.h.
 168 # Used by Emacs.
 169 AC_DEFUN([gl_ASSERT_NO_GNULIB_POSIXCHECK],
 170 [
 171   dnl Override gl_WARN_ON_USE_PREPARE.
 172   dnl But hide this definition from 'aclocal'.
 173   AC_DEFUN([gl_W][ARN_ON_USE_PREPARE], [])
 174 ])
 175
 176 # gl_ASSERT_NO_GNULIB_TESTS
 177 # asserts that there will be no gnulib tests in the scope of the configure.ac
 178 # and thereby enables an optimization of config.h.
 179 # Used by Emacs.
 180 AC_DEFUN([gl_ASSERT_NO_GNULIB_TESTS],
 181 [
 182   dnl Override gl_MODULE_INDICATOR_FOR_TESTS.
 183   AC_DEFUN([gl_MODULE_INDICATOR_FOR_TESTS], [])
 184 ])
 185
 186 # Test whether <features.h> exists.
 187 # Set HAVE_FEATURES_H.
 188 AC_DEFUN([gl_FEATURES_H],
 189 [
 190   AC_CHECK_HEADERS_ONCE([features.h])
 191   if test $ac_cv_header_features_h = yes; then
 192     HAVE_FEATURES_H=1
 193   else
 194     HAVE_FEATURES_H=0
 195   fi
 196   AC_SUBST([HAVE_FEATURES_H])
 197 ])
 198
 199 # m4_foreach_w
 200 # is a backport of autoconf-2.59c's m4_foreach_w.
 201 # Remove this macro when we can assume autoconf >= 2.60.
 202 m4_ifndef([m4_foreach_w],
 203   [m4_define([m4_foreach_w],
 204     [m4_foreach([$1], m4_split(m4_normalize([$2]), [ ]), [$3])])])
 205
 206 # AS_VAR_IF(VAR, VALUE, [IF-MATCH], [IF-NOT-MATCH])
 207 # ----------------------------------------------------
 208 # Backport of autoconf-2.63b's macro.
 209 # Remove this macro when we can assume autoconf >= 2.64.
 210 m4_ifndef([AS_VAR_IF],
 211 [m4_define([AS_VAR_IF],
 212 [AS_IF([test x"AS_VAR_GET([$1])" = x""$2], [$3], [$4])])])
 213
 214 # AC_PROG_MKDIR_P
 215 # is a backport of autoconf-2.60's AC_PROG_MKDIR_P, with a fix
 216 # for interoperability with automake-1.9.6 from autoconf-2.62.
 217 # Remove this macro when we can assume autoconf >= 2.62 or
 218 # autoconf >= 2.60 && automake >= 1.10.
 219 m4_ifdef([AC_PROG_MKDIR_P], [
 220   dnl For automake-1.9.6 && autoconf < 2.62: Ensure MKDIR_P is AC_SUBSTed.
 221   m4_define([AC_PROG_MKDIR_P],
 222     m4_defn([AC_PROG_MKDIR_P])[
 223     AC_SUBST([MKDIR_P])])], [
 224   dnl For autoconf < 2.60: Backport of AC_PROG_MKDIR_P.
 225   AC_DEFUN_ONCE([AC_PROG_MKDIR_P],
 226     [AC_REQUIRE([AM_PROG_MKDIR_P])dnl defined by automake
 227      MKDIR_P='$(mkdir_p)'
 228      AC_SUBST([MKDIR_P])])])
 229
 230 # AC_C_RESTRICT
 231 # This definition overrides the AC_C_RESTRICT macro from autoconf 2.60..2.61,
 232 # so that mixed use of GNU C and GNU C++ and mixed use of Sun C and Sun C++
 233 # works.
 234 # This definition can be removed once autoconf >= 2.62 can be assumed.
 235 m4_if(m4_version_compare(m4_defn([m4_PACKAGE_VERSION]),[2.62]),[-1],[
 236 AC_DEFUN([AC_C_RESTRICT],
 237 [AC_CACHE_CHECK([for C/C++ restrict keyword], [ac_cv_c_restrict],
 238   [ac_cv_c_restrict=no
 239    # The order here caters to the fact that C++ does not require restrict.
 240    for ac_kw in __restrict __restrict__ _Restrict restrict; do
 241      AC_COMPILE_IFELSE([AC_LANG_PROGRAM(
 242       [[typedef int * int_ptr;
 243         int foo (int_ptr $ac_kw ip) {
 244         return ip[0];
 245        }]],
 246       [[int s[1];
 247         int * $ac_kw t = s;
 248         t[0] = 0;
 249         return foo(t)]])],
 250       [ac_cv_c_restrict=$ac_kw])
 251      test "$ac_cv_c_restrict" != no && break
 252    done
 253   ])
 254  AH_VERBATIM([restrict],
 255 [/* Define to the equivalent of the C99 'restrict' keyword, or to
 256    nothing if this is not supported.  Do not define if restrict is
 257    supported directly.  */
 258 #undef restrict
 259 /* Work around a bug in Sun C++: it does not support _Restrict, even
 260    though the corresponding Sun C compiler does, which causes
 261    "#define restrict _Restrict" in the previous line.  Perhaps some future
 262    version of Sun C++ will work with _Restrict; if so, it'll probably
 263    define __RESTRICT, just as Sun C does.  */
 264 #if defined __SUNPRO_CC && !defined __RESTRICT
 265 # define _Restrict
 266 #endif])
 267  case $ac_cv_c_restrict in
 268    restrict) ;;
 269    no) AC_DEFINE([restrict], []) ;;
 270    *)  AC_DEFINE_UNQUOTED([restrict], [$ac_cv_c_restrict]) ;;
 271  esac
 272 ])
 273 ])
 274
 275 # gl_BIGENDIAN
 276 # is like AC_C_BIGENDIAN, except that it can be AC_REQUIREd.
 277 # Note that AC_REQUIRE([AC_C_BIGENDIAN]) does not work reliably because some
 278 # macros invoke AC_C_BIGENDIAN with arguments.
 279 AC_DEFUN([gl_BIGENDIAN],
 280 [
 281   AC_C_BIGENDIAN
 282 ])
 283
 284 # gl_CACHE_VAL_SILENT(cache-id, command-to-set-it)
 285 # is like AC_CACHE_VAL(cache-id, command-to-set-it), except that it does not
 286 # output a spurious "(cached)" mark in the midst of other configure output.
 287 # This macro should be used instead of AC_CACHE_VAL when it is not surrounded
 288 # by an AC_MSG_CHECKING/AC_MSG_RESULT pair.
 289 AC_DEFUN([gl_CACHE_VAL_SILENT],
 290 [
 291   saved_as_echo_n="$as_echo_n"
 292   as_echo_n=':'
 293   AC_CACHE_VAL([$1], [$2])
 294   as_echo_n="$saved_as_echo_n"
 295 ])