Module: ppl/ppl Branch: master Commit: ccd09e698f00e26a8dc4ccc2265843e6b9ec1598 URL: http://www.cs.unipr.it/git/gitweb.cgi?p=ppl/ppl.git;a=commit;h=ccd09e698f00e...

Author: Roberto Bagnara bagnara@cs.unipr.it Date: Sat Feb 11 20:51:31 2012 +0100

INT_MIN % -1 is undefined behavior in C++11. The PPL has been proven to be immune to this potential problem by ECLAIR. (Thanks to Rene Sugar.)

---

TODO | 7 ---- configure.ac | 5 +-- m4/ac_cxx_remainder_bug.m4 | 71 -------------------------------------------- src/checked.cc | 1 + 4 files changed, 2 insertions(+), 82 deletions(-)

diff --git a/TODO b/TODO index 6ea8729..271fb42 100644 --- a/TODO +++ b/TODO @@ -23,13 +23,6 @@ Enhancements for PPL 0.12 or later versions Explain it in README.configure. - Ensure the tests in tests/MIP_Problem/* cover every line of code in MIP_Problem.*. -- Define functions rem() and remp() to compute the remainder of division - in the general case, for rem(), and in the case where the second - argument is known to be positive, for remp(). In the implementation - of rem(), if CXX_HAS_REMAINDER_BUG is nonzero, a suitable workaround - should be implemented to circumvent the INT_MIN % -1 bug. - rem() and remp() should be used (with a strong preference to the second, - of course) wherever we now use operator%(). - Suppose we want to sum three numbers, and suppose we do it by

add(T& to, const T& x, const T& y, const T& z) { diff --git a/configure.ac b/configure.ac index 898f540..eed647d 100644 --- a/configure.ac +++ b/configure.ac @@ -24,7 +24,7 @@ # Process this file with Autoconf to produce a configure script.

# Every other copy of the package version number gets its value from here. -AC_INIT([the Parma Polyhedra Library], [0.12pre3], [ppl-devel@cs.unipr.it], [ppl]) +AC_INIT([the Parma Polyhedra Library], [0.12pre4], [ppl-devel@cs.unipr.it], [ppl])

# Minimum Autoconf version required. AC_PREREQ(2.61) @@ -780,9 +780,6 @@ AC_CXX_SUPPORTS_ZERO_LENGTH_ARRAYS # Check whether the IEEE inexact flag is supported in C++. AC_CXX_SUPPORTS_IEEE_INEXACT_FLAG

-# Check whether the C++ compiler has the remainder bug. -AC_CXX_HAS_REMAINDER_BUG - # Check whether the C++ compiler supports __attribute__ ((weak)). AC_CXX_SUPPORTS_ATTRIBUTE_WEAK

diff --git a/m4/ac_cxx_remainder_bug.m4 b/m4/ac_cxx_remainder_bug.m4 deleted file mode 100644 index 0dfb146..0000000 --- a/m4/ac_cxx_remainder_bug.m4 +++ /dev/null @@ -1,71 +0,0 @@ -dnl A function to check whether the C++ compiler has the `remainder' bug. -dnl Copyright (C) 2001-2010 Roberto Bagnara bagnara@cs.unipr.it -dnl Copyright (C) 2010-2012 BUGSENG srl (http://bugseng.com) -dnl -dnl This file is part of the Parma Polyhedra Library (PPL). -dnl -dnl The PPL is free software; you can redistribute it and/or modify it -dnl under the terms of the GNU General Public License as published by the -dnl Free Software Foundation; either version 3 of the License, or (at your -dnl option) any later version. -dnl -dnl The PPL is distributed in the hope that it will be useful, but WITHOUT -dnl ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or -dnl FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -dnl for more details. -dnl -dnl You should have received a copy of the GNU General Public License -dnl along with this program; if not, write to the Free Software Foundation, -dnl Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02111-1307, USA. -dnl -dnl For the most up-to-date information see the Parma Polyhedra Library -dnl site: http://bugseng.com/products/ppl/ . - -AC_DEFUN([AC_CXX_HAS_REMAINDER_BUG], -[ - -ac_save_CPPFLAGS="$CPPFLAGS" -ac_save_LIBS="$LIBS" -AC_LANG_PUSH(C++) - -AC_MSG_CHECKING([if the compiler has the remainder bug]) -AC_RUN_IFELSE([AC_LANG_SOURCE([[ -#include <climits> - -int minus_one(int n) { - return (n+1)*(n-1)-n*n; -} - -int p(int x, int y) { - int z = x % y; - return z; -} - -int main(int argc, char** argv) { - if (p(INT_MIN, minus_one(argc)) != 0) - return 1; - else - return 0; -} -]])], - AC_MSG_RESULT(no) - ac_cv_cxx_has_remainder_bug=no, - AC_MSG_RESULT(yes) - ac_cv_cxx_has_remainder_bug=yes, - AC_MSG_RESULT([assuming yes]) - ac_cv_cxx_has_remainder_bug=yes) - -if test x"$ac_cv_cxx_has_remainder_bug" = xyes -then - value=1 -else - value=0 -fi -AC_DEFINE_UNQUOTED(PPL_CXX_HAS_REMAINDER_BUG, $value, - [Not zero if the C++ compiler has the remainder bug.]) - -AC_LANG_POP(C++) -CPPFLAGS="$ac_save_CPPFLAGS" -LIBS="$ac_save_LIBS" -]) - diff --git a/src/checked.cc b/src/checked.cc index 104fecf..93a933c 100644 --- a/src/checked.cc +++ b/src/checked.cc @@ -278,6 +278,7 @@ parse_number_part(std::istream& is, number_struct& numer) { goto unexpected; exp: state = EXPONENT; + PPL_ASSERT(numer.base >= 2); max_exp_div = LONG_MAX / numer.base; max_exp_rem = static_cast<int>(LONG_MAX % numer.base); if (!is.get(c))