Changeset 0a3fa3 in git for libpolys/coeffs/longrat.cc

Timestamp:

Dec 22, 2011, 8:33:58 PM (11 years ago)

Author:

Oleksandr Motsak <motsak@…>

Branches:

(u'spielwiese', '0d6b7fcd9813a1ca1ed4220cfa2b104b97a0a003')

Children:

1cbb1f452324cf72b33ef5a1cb6256d97bcbcbd0

Parents:

113ed4ea1440de5024b690416c6b95d02b73bdf1

git-author:

Oleksandr Motsak <motsak@mathematik.uni-kl.de>2011-12-22 20:33:58+01:00

git-committer:

Oleksandr Motsak <motsak@mathematik.uni-kl.de>2012-01-06 21:59:37+01:00

Message:

bug in nlModP (longrat.cc:1294)

ADD: test mapping of -7/5 from Q into F_1000000007 (wrong on 32bit due to an integer overflow in nlModP)

File:

• libpolys/coeffs/longrat.cc (modified) (1 diff)

libpolys/coeffs/longrat.cc

@@ -1292 +1292 @@
      s = u1;
      if (s < 0) s+=p;
-     u=(s*((long)iz)) % ((long)p);
+     u=(s*((long)iz)) % ((long)p); // BUG: integer overflow!!!
      return (int)u;
   }