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Hi! ldbl-96 llroundl(4294967295.5) returns 0, although it should return 4294967296LL. The problem is that on this input i0 == 0xffffffff, i1 == 0x80000000, j0 == 31, so llroundl rounds up (by doing ++i0, which overflows and is suddenly 0). Fixed with a patch below, where the rounding is already done on long long variable. 2001-06-04 Jakub Jelinek <jakub@redhat.com> * math/libm-test.inc (llround_test): Add two new llround tests. * sysdeps/ieee754/ldbl-96/s_llroundl.c (__llroundl): Don't allow overflow when rounding away from zero. --- libc/math/libm-test.inc.jj Wed May 23 09:21:45 2001 +++ libc/math/libm-test.inc Mon Jun 4 10:01:59 2001 @@ -3302,6 +3302,13 @@ llround_test (void) /* 0x100000000000000 */ TEST_f_L (llround, 72057594037927936.0, 72057594037927936LL); +#ifndef TEST_FLOAT + /* 0x100000000 */ + TEST_f_L (llround, 4294967295.5, 4294967296LL); + /* 0x200000000 */ + TEST_f_L (llround, 8589934591.5, 8589934592LL); +#endif + END (llround); } --- libc/sysdeps/ieee754/ldbl-96/s_llroundl.c.jj Wed Jul 14 02:14:08 1999 +++ libc/sysdeps/ieee754/ldbl-96/s_llroundl.c Mon Jun 4 09:50:49 2001 @@ -1,5 +1,5 @@ /* Round long double value to long long int. - Copyright (C) 1997 Free Software Foundation, Inc. + Copyright (C) 1997, 2001 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. @@ -59,13 +59,13 @@ __llroundl (long double x) else { u_int32_t j = i1 + (0x80000000 >> (j0 - 31)); + + result = (long long int) i0; if (j < i1) - ++i0; + ++result; - if (j0 == 31) - result = (long long int) i0; - else - result = ((long long int) i0 << (j0 - 31)) | (j >> (63 - j0)); + if (j0 > 31) + result = (result << (j0 - 31)) | (j >> (63 - j0)); } } else Jakub
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