acinclude.m4

   1 dnl Turn on the additional warnings last, so -Werror doesn't affect other tests.
   2 AC_DEFUN([IMENDIO_COMPILE_WARNINGS],[
   3    if test -f $srcdir/autogen.sh; then
   4         default_compile_warnings="error"
   5     else
   6         default_compile_warnings="no"
   7     fi
   8
   9     AC_ARG_WITH(compile-warnings, [  --with-compile-warnings=[no/yes/error] Compiler warnings ], [enable_compile_warnings="$withval"], [enable_compile_warnings="$default_compile_warnings"])
  10
  11     warnCFLAGS=
  12     if test "x$GCC" != xyes; then
  13         enable_compile_warnings=no
  14     fi
  15
  16     warning_flags=
  17     realsave_CFLAGS="$CFLAGS"
  18
  19     case "$enable_compile_warnings" in
  20     no)
  21         warning_flags=
  22         ;;
  23     yes)
  24         warning_flags="-Wall -Wunused -Wmissing-prototypes -Wmissing-declarations"
  25         ;;
  26     maximum|error)
  27         warning_flags="-Wall -Wunused -Wchar-subscripts -Wmissing-declarations -Wmissing-prototypes -Wnested-externs -Wpointer-arith -Wcast-align -std=c99"
  28         CFLAGS="$warning_flags $CFLAGS"
  29         for option in -Wno-sign-compare -Wno-pointer-sign; do
  30                 SAVE_CFLAGS="$CFLAGS"
  31                 CFLAGS="$CFLAGS $option"
  32                 AC_MSG_CHECKING([whether gcc understands $option])
  33                 AC_TRY_COMPILE([], [],
  34                         has_option=yes,
  35                         has_option=no,)
  36                 CFLAGS="$SAVE_CFLAGS"
  37                 AC_MSG_RESULT($has_option)
  38                 if test $has_option = yes; then
  39                   warning_flags="$warning_flags $option"
  40                 fi
  41                 unset has_option
  42                 unset SAVE_CFLAGS
  43         done
  44         unset option
  45         if test "$enable_compile_warnings" = "error" ; then
  46             warning_flags="$warning_flags -Werror"
  47         fi
  48         ;;
  49     *)
  50         AC_MSG_ERROR(Unknown argument '$enable_compile_warnings' to --enable-compile-warnings)
  51         ;;
  52     esac
  53     CFLAGS="$realsave_CFLAGS"
  54     AC_MSG_CHECKING(what warning flags to pass to the C compiler)
  55     AC_MSG_RESULT($warning_flags)
  56
  57     WARN_CFLAGS="$warning_flags"
  58     AC_SUBST(WARN_CFLAGS)
  59 ])
  60