From 0e597471aff206460f02999d6ea9e1e3243ef945 Mon Sep 17 00:00:00 2001 From: Nick Mathewson Date: Thu, 7 Feb 2013 16:23:48 -0500 Subject: Use a nicely written autoconf macro to determine the sign of a type This beats our old implementation, which wouldn't work when cross-compiling --- m4/ax_check_sign.m4 | 54 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 54 insertions(+) create mode 100644 m4/ax_check_sign.m4 (limited to 'm4') diff --git a/m4/ax_check_sign.m4 b/m4/ax_check_sign.m4 new file mode 100644 index 000000000..104b17014 --- /dev/null +++ b/m4/ax_check_sign.m4 @@ -0,0 +1,54 @@ +# =========================================================================== +# http://www.gnu.org/software/autoconf-archive/ax_check_sign.html +# =========================================================================== +# +# SYNOPSIS +# +# AX_CHECK_SIGN (TYPE, [ACTION-IF-SIGNED], [ACTION-IF-UNSIGNED], [INCLUDES]) +# +# DESCRIPTION +# +# Checks whether TYPE is signed or not. If no INCLUDES are specified, the +# default includes are used. If ACTION-IF-SIGNED is given, it is +# additional shell code to execute when the type is signed. If +# ACTION-IF-UNSIGNED is given, it is executed when the type is unsigned. +# +# This macro assumes that the type exists. Therefore the existence of the +# type should be checked before calling this macro. For example: +# +# AC_CHECK_HEADERS([wchar.h]) +# AC_CHECK_TYPE([wchar_t],,[ AC_MSG_ERROR([Type wchar_t not found.]) ]) +# AX_CHECK_SIGN([wchar_t], +# [ AC_DEFINE(WCHAR_T_SIGNED, 1, [Define if wchar_t is signed]) ], +# [ AC_DEFINE(WCHAR_T_UNSIGNED, 1, [Define if wchar_t is unsigned]) ], [ +# #ifdef HAVE_WCHAR_H +# #include +# #endif +# ]) +# +# LICENSE +# +# Copyright (c) 2008 Ville Laurikari +# +# Copying and distribution of this file, with or without modification, are +# permitted in any medium without royalty provided the copyright notice +# and this notice are preserved. This file is offered as-is, without any +# warranty. + +#serial 6 + +AU_ALIAS([VL_CHECK_SIGN], [AX_CHECK_SIGN]) +AC_DEFUN([AX_CHECK_SIGN], [ + typename=`echo $1 | sed "s/@<:@^a-zA-Z0-9_@:>@/_/g"` + AC_CACHE_CHECK([whether $1 is signed], ax_cv_decl_${typename}_signed, [ + AC_TRY_COMPILE([$4], + [ int foo @<:@ 1 - 2 * !((($1) -1) < 0) @:>@ ], + [ eval "ax_cv_decl_${typename}_signed=\"yes\"" ], + [ eval "ax_cv_decl_${typename}_signed=\"no\"" ])]) + symbolname=`echo $1 | sed "s/@<:@^a-zA-Z0-9_@:>@/_/g" | tr "a-z" "A-Z"` + if eval "test \"\${ax_cv_decl_${typename}_signed}\" = \"yes\""; then + $2 + elif eval "test \"\${ax_cv_decl_${typename}_signed}\" = \"no\""; then + $3 + fi +])dnl -- cgit v1.2.3