Mercurial > gnulib
view lib/ffsl.h @ 40231:9b3c79fdfe0b
strtod: fix clash with strtold
Problem reported for RHEL 5 by Jesse Caldwell (Bug#34817).
* lib/strtod.c (compute_minus_zero, minus_zero):
Simplify by remving the macro / external variable,
and having just a function. User changed. This avoids
the need for an external variable that might clash.
author | Paul Eggert <eggert@cs.ucla.edu> |
---|---|
date | Mon, 11 Mar 2019 16:40:29 -0700 |
parents | b06060465f09 |
children |
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/* ffsl.h -- find the first set bit in a word. Copyright (C) 2011-2019 Free Software Foundation, Inc. This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <https://www.gnu.org/licenses/>. */ /* Written by Eric Blake. */ /* This file is meant to be included by ffsl.c and ffsll.c, after they have defined FUNC and TYPE. */ #include <config.h> /* Specification. */ #include <string.h> #include <limits.h> #include <strings.h> #if !defined FUNC || !defined TYPE # error #endif int FUNC (TYPE i) { #if (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4)) && defined GCC_BUILTIN return GCC_BUILTIN (i); #else unsigned TYPE j = i; /* Split j into chunks, and look at one chunk after the other. */ enum { chunk_bits = CHAR_BIT * sizeof (unsigned int) }; /* The number of chunks is ceil (sizeof (TYPE) / sizeof (unsigned int)) = (sizeof (TYPE) - 1) / sizeof (unsigned int) + 1. */ enum { chunk_count = (sizeof (TYPE) - 1) / sizeof (unsigned int) + 1 }; if (chunk_count > 1) { size_t k; /* It is tempting to write if (!j) here, but if we do this, Solaris 10/x86 "cc -O" miscompiles the code. */ if (!i) return 0; /* Unroll the first loop round. k = 0. */ if ((unsigned int) j) return ffs ((unsigned int) j); /* Generic loop. */ for (k = 1; k < chunk_count - 1; k++) if ((unsigned int) (j >> (k * chunk_bits)) != 0) return k * chunk_bits + ffs ((unsigned int) (j >> (k * chunk_bits))); } /* Last loop round. k = chunk_count - 1. */ return (chunk_count - 1) * chunk_bits + ffs ((unsigned int) (j >> ((chunk_count - 1) * chunk_bits))); #endif }