m4/warnings.m4

   1 # warnings.m4 serial 7
   2 dnl Copyright (C) 2008-2012 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 dnl 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.
  12 m4_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.
  25 AC_DEFUN([gl_COMPILER_OPTION_IF],
  26 [AS_VAR_PUSHDEF([gl_Warn], [gl_cv_warn_[]_AC_LANG_ABBREV[]_$1])dnl
  27 AS_VAR_PUSHDEF([gl_Flags], [_AC_LANG_PREFIX[]FLAGS])dnl
  28 AC_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 ])
  36 AS_VAR_IF(gl_Warn, [yes], [$2], [$3])
  37 AS_VAR_POPDEF([gl_Flags])dnl
  38 AS_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.
  49 AC_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])
  54 m4_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: