config/warnings.m4

   1 # Autoconf include file defining macros related to compile-time warnings.
   2
   3 # Copyright 2004, 2005, 2007 Free Software Foundation, Inc.
   4
   5 #This file is part of GCC.
   6
   7 #GCC is free software; you can redistribute it and/or modify it under
   8 #the terms of the GNU General Public License as published by the Free
   9 #Software Foundation; either version 2, or (at your option) any later
  10 #version.
  11
  12 #GCC is distributed in the hope that it will be useful, but WITHOUT
  13 #ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 #FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 #for more details.
  16
  17 #You should have received a copy of the GNU General Public License
  18 #along with GCC; see the file COPYING.  If not, write to the Free
  19 #Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
  20 #02110-1301, USA.
  21
  22 # ACX_PROG_CC_WARNING_OPTS(WARNINGS, [VARIABLE = WARN_CFLAGS@)
  23 #   Sets @VARIABLE@ to the subset of the given options which the
  24 #   compiler accepts.
  25 AC_DEFUN([ACX_PROG_CC_WARNING_OPTS],
  26 [AC_REQUIRE([AC_PROG_CC])dnl
  27 m4_pushdef([acx_Var], [m4_default([$2], [WARN_CFLAGS])])dnl
  28 AC_SUBST(acx_Var)dnl
  29 acx_Var=
  30 save_CFLAGS="$CFLAGS"
  31 for option in $1; do
  32   AS_VAR_PUSHDEF([acx_Woption], [acx_cv_prog_cc_warning_$option])
  33   AC_CACHE_CHECK([whether $CC supports $option], acx_Woption,
  34     [CFLAGS="$option"
  35     AC_COMPILE_IFELSE([AC_LANG_PROGRAM([],[])],
  36       [AS_VAR_SET(acx_Woption, yes)],
  37       [AS_VAR_SET(acx_Woption, no)])
  38   ])
  39   AS_IF([test AS_VAR_GET(acx_Woption) = yes],
  40         [acx_Var="$acx_Var${acx_Var:+ }$option"])
  41   AS_VAR_POPDEF([acx_Woption])dnl
  42 done
  43 CFLAGS="$save_CFLAGS"
  44 m4_popdef([acx_Var])dnl
  45 ])# ACX_PROG_CC_WARNING_OPTS
  46
  47 # ACX_PROG_CC_WARNING_ALMOST_PEDANTIC(WARNINGS, [VARIABLE = WARN_PEDANTIC)
  48 #   Append to VARIABLE "-pedantic" + the argument, if the compiler is GCC
  49 #   and accepts all of those options simultaneously, otherwise to nothing.
  50 AC_DEFUN([ACX_PROG_CC_WARNING_ALMOST_PEDANTIC],
  51 [AC_REQUIRE([AC_PROG_CC])dnl
  52 m4_pushdef([acx_Var], [m4_default([$2], [WARN_PEDANTIC])])dnl
  53 AC_SUBST(acx_Var)dnl
  54 AS_VAR_PUSHDEF([acx_Pedantic], [acx_cv_prog_cc_pedantic_$1])dnl
  55 acx_Var=
  56 AS_IF([test "$GCC" = yes],
  57 [AC_CACHE_CHECK([whether $CC supports -pedantic $1], acx_Pedantic,
  58 [save_CFLAGS="$CFLAGS"
  59 CFLAGS="-pedantic $1"
  60 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([],[])],
  61    [AS_VAR_SET(acx_Pedantic, yes)],
  62    [AS_VAR_SET(acx_Pedantic, no)])
  63 CFLAGS="$save_CFLAGS"])
  64 AS_IF([test AS_VAR_GET(acx_Pedantic) = yes],
  65       [acx_Var="$acx_Var${acx_Var:+ }-pedantic $1"])
  66 ])
  67 AS_VAR_POPDEF([acx_Pedantic])dnl
  68 m4_popdef([acx_Var])dnl
  69 ])# ACX_PROG_CC_WARNING_ALMOST_PEDANTIC
  70
  71 # ACX_PROG_CC_WARNINGS_ARE_ERRORS([x.y.z])
  72 #   sets WERROR to "-Werror" if the compiler is GCC >=x.y.z, or if
  73 #   --enable-werror-always was given on the command line, otherwise
  74 #   to nothing.
  75 #   If the argument is the word "manual" instead of a version number,
  76 #   then WERROR will be set to -Werror only if --enable-werror-always
  77 #   appeared on the configure command line.
  78 AC_DEFUN([ACX_PROG_CC_WARNINGS_ARE_ERRORS],
  79 [AC_REQUIRE([AC_PROG_CC])dnl
  80 AC_SUBST([WERROR])dnl
  81 WERROR=
  82 AC_ARG_ENABLE(werror-always,
  83     AS_HELP_STRING([--enable-werror-always],
  84                    [enable -Werror despite compiler version]),
  85 [], [enable_werror_always=no])
  86 AS_IF([test $enable_werror_always = yes],
  87       [WERROR=-Werror],
  88  m4_if($1, [manual],,
  89  [AS_VAR_PUSHDEF([acx_GCCvers], [acx_cv_prog_cc_gcc_$1_or_newer])dnl
  90   AC_CACHE_CHECK([whether $CC is GCC >=$1], acx_GCCvers,
  91     [set fnord `echo $1 | tr '.' ' '`
  92      shift
  93      AC_PREPROC_IFELSE(
  94 [#if __GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__ \
  95   < [$]1 * 10000 + [$]2 * 100 + [$]3
  96 #error insufficient
  97 #endif],
  98    [AS_VAR_SET(acx_GCCvers, yes)],
  99    [AS_VAR_SET(acx_GCCvers, no)])])
 100  AS_IF([test AS_VAR_GET(acx_GCCvers) = yes],
 101        [WERROR=-WerrorB])
 102   AS_VAR_POPDEF([acx_GCCvers])]))
 103 ])# ACX_PROG_CC_WARNINGS_ARE_ERRORS