macros2/compiler-flags.m4

   1 dnl GNOME_COMPILE_WARNINGS
   2 dnl Turn on many useful compiler warnings
   3 dnl For now, only works on GCC
   4 AC_DEFUN([GNOME_COMPILE_WARNINGS],[
   5     dnl ******************************
   6     dnl More compiler warnings
   7     dnl ******************************
   8
   9     if test -z "$1" ; then
  10         default_compile_warnings=yes
  11     else
  12         default_compile_warnings="$1"
  13     fi
  14
  15     AC_ARG_ENABLE(compile-warnings,
  16     [  --enable-compile-warnings=[no/minimum/yes/maximum/error] Turn on compiler warnings.],, [enable_compile_warnings="$default_compile_warnings"])
  17
  18     warnCFLAGS=
  19     if test "x$GCC" != xyes; then
  20         enable_compile_warnings=no
  21     fi
  22
  23     warning_flags=
  24     realsave_CFLAGS="$CFLAGS"
  25
  26     case "$enable_compile_warnings" in
  27     no)
  28         warning_flags=
  29         ;;
  30     minimum)
  31         warning_flags="-Wall"
  32         ;;
  33     yes)
  34         warning_flags="-Wall -Wmissing-prototypes"
  35         ;;
  36     maximum|error)
  37         warning_flags="-Wall -Wmissing-prototypes -Wnested-externs -Wpointer-arith"
  38         CFLAGS="$warning_flags $CFLAGS"
  39         for option in -Wno-sign-compare; do
  40                 SAVE_CFLAGS="$CFLAGS"
  41                 CFLAGS="$CFLAGS $option"
  42                 AC_MSG_CHECKING([whether gcc understands $option])
  43                 AC_TRY_COMPILE([], [],
  44                         has_option=yes,
  45                         has_option=no,)
  46                 CFLAGS="$SAVE_CFLAGS"
  47                 AC_MSG_RESULT($has_option)
  48                 if test $has_option = yes; then
  49                   warning_flags="$warning_flags $option"
  50                 fi
  51                 unset has_option
  52                 unset SAVE_CFLAGS
  53         done
  54         unset option
  55         if test "$enable_compile_warnings" = "error" ; then
  56             warning_flags="$warning_flags -Werror"
  57         fi
  58         ;;
  59     *)
  60         AC_MSG_ERROR(Unknown argument '$enable_compile_warnings' to --enable-compile-warnings)
  61         ;;
  62     esac
  63     CFLAGS="$realsave_CFLAGS"
  64     AC_MSG_CHECKING(what warning flags to pass to the C compiler)
  65     AC_MSG_RESULT($warning_flags)
  66
  67     AC_ARG_ENABLE(iso-c,
  68     [  --enable-iso-c          Try to warn if code is not ISO C ],,
  69     enable_iso_c=no)
  70
  71     AC_MSG_CHECKING(what language compliance flags to pass to the C compiler)
  72     complCFLAGS=
  73     if test "x$enable_iso_c" != "xno"; then
  74         if test "x$GCC" = "xyes"; then
  75         case " $CFLAGS " in
  76             *[\ \       ]-ansi[\ \      ]*) ;;
  77             *) complCFLAGS="$complCFLAGS -ansi" ;;
  78         esac
  79         case " $CFLAGS " in
  80             *[\ \       ]-pedantic[\ \  ]*) ;;
  81             *) complCFLAGS="$complCFLAGS -pedantic" ;;
  82         esac
  83         fi
  84     fi
  85     AC_MSG_RESULT($complCFLAGS)
  86
  87     WARN_CFLAGS="$warning_flags $complCFLAGS"
  88     AC_SUBST(WARN_CFLAGS)
  89 ])
  90
  91 dnl For C++, do basically the same thing.
  92
  93 AC_DEFUN([GNOME_CXX_WARNINGS],[
  94   AC_ARG_ENABLE(cxx-warnings,
  95     [  --enable-cxx-warnings=[no/minimum/yes]   Turn on compiler warnings.],,enable_cxx_warnings=minimum)
  96
  97   AC_MSG_CHECKING(what warning flags to pass to the C++ compiler)
  98   warnCXXFLAGS=
  99   if test "x$GCC" != xyes; then
 100     enable_compile_warnings=no
 101   fi
 102   if test "x$enable_cxx_warnings" != "xno"; then
 103     if test "x$GCC" = "xyes"; then
 104       case " $CXXFLAGS " in
 105       *[\ \     ]-Wall[\ \      ]*) ;;
 106       *) warnCXXFLAGS="-Wall -Wno-unused" ;;
 107       esac
 108
 109       ## -W is not all that useful.  And it cannot be controlled
 110       ## with individual -Wno-xxx flags, unlike -Wall
 111       if test "x$enable_cxx_warnings" = "xyes"; then
 112         warnCXXFLAGS="$warnCXXFLAGS -Wmissing-prototypes -Wmissing-declarations -Wshadow -Woverloaded-virtual"
 113       fi
 114     fi
 115   fi
 116   AC_MSG_RESULT($warnCXXFLAGS)
 117
 118    AC_ARG_ENABLE(iso-cxx,
 119      [  --enable-iso-cxx          Try to warn if code is not ISO C++ ],,
 120      enable_iso_cxx=no)
 121
 122    AC_MSG_CHECKING(what language compliance flags to pass to the C++ compiler)
 123    complCXXFLAGS=
 124    if test "x$enable_iso_cxx" != "xno"; then
 125      if test "x$GCC" = "xyes"; then
 126       case " $CXXFLAGS " in
 127       *[\ \     ]-ansi[\ \      ]*) ;;
 128       *) complCXXFLAGS="$complCXXFLAGS -ansi" ;;
 129       esac
 130
 131       case " $CXXFLAGS " in
 132       *[\ \     ]-pedantic[\ \  ]*) ;;
 133       *) complCXXFLAGS="$complCXXFLAGS -pedantic" ;;
 134       esac
 135      fi
 136    fi
 137   AC_MSG_RESULT($complCXXFLAGS)
 138   if test "x$cxxflags_set" != "xyes"; then
 139     CXXFLAGS="$CXXFLAGS $warnCXXFLAGS $complCXXFLAGS"
 140     cxxflags_set=yes
 141     AC_SUBST(cxxflags_set)
 142   fi
 143 ])