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emacs/m4/count-leading-zeros.m4
Paul Eggert 74f87fd111 logb now works correctly on large integers
* admin/merge-gnulib (GNULIB_MODULES): Add count-leading-zeros.
* etc/NEWS: Document the change.
* lib/count-leading-zeros.c, lib/count-leading-zeros.h:
* m4/count-leading-zeros.m4: New files, copied from Gnulib.
* lib/gnulib.mk, m4/gnulib-comp.m4: Regenerate.
* src/floatfns.c: Include count-leading-zeros.h.
(Flogb): Do not convert fixnum to float before taking the log,
as the rounding error can cause the answer to be off by 1.
* src/lisp.h (EMACS_UINT_WIDTH): New constant.
* test/src/floatfns-tests.el (logb-extreme-fixnum): New test.
2017-03-03 09:19:08 -08:00

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# count-leading-zeros.m4 serial 2
dnl Copyright (C) 2012-2017 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.
AC_DEFUN([gl_COUNT_LEADING_ZEROS],
[
dnl We don't need (and can't compile) count_leading_zeros_ll
dnl unless the type 'unsigned long long int' exists.
AC_REQUIRE([AC_TYPE_UNSIGNED_LONG_LONG_INT])
])