2011-01-09 01:20:28 +00:00
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/* intprops.h -- properties of integer types
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Copyright (C) 2001-2005, 2009-2011 Free Software Foundation, Inc.
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This program is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>. */
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/* Written by Paul Eggert. */
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2011-05-16 00:51:54 +00:00
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#ifndef _GL_INTPROPS_H
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#define _GL_INTPROPS_H
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2011-01-09 01:20:28 +00:00
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2011-05-16 00:51:54 +00:00
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#include <limits.h>
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/* Return a integer value, converted to the same type as the integer
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expression E after integer type promotion. V is the unconverted value.
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E should not have side effects. */
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#define _GL_INT_CONVERT(e, v) ((e) - (e) + (v))
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2011-01-09 01:20:28 +00:00
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2011-05-22 21:02:48 +00:00
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/* Act like _GL_INT_CONVERT (E, -V) but work around a bug in IRIX 6.5 cc; see
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<http://lists.gnu.org/archive/html/bug-gnulib/2011-05/msg00406.html>. */
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#define _GL_INT_NEGATE_CONVERT(e, v) ((e) - (e) - (v))
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2011-01-09 01:20:28 +00:00
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/* The extra casts in the following macros work around compiler bugs,
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e.g., in Cray C 5.0.3.0. */
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/* True if the arithmetic type T is an integer type. bool counts as
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an integer. */
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2011-05-16 00:51:54 +00:00
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#define TYPE_IS_INTEGER(t) ((t) 1.5 == 1)
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2011-01-09 01:20:28 +00:00
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/* True if negative values of the signed integer type T use two's
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complement, ones' complement, or signed magnitude representation,
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respectively. Much GNU code assumes two's complement, but some
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people like to be portable to all possible C hosts. */
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2011-05-16 00:51:54 +00:00
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#define TYPE_TWOS_COMPLEMENT(t) ((t) ~ (t) 0 == (t) -1)
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#define TYPE_ONES_COMPLEMENT(t) ((t) ~ (t) 0 == 0)
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#define TYPE_SIGNED_MAGNITUDE(t) ((t) ~ (t) 0 < (t) -1)
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/* True if the signed integer expression E uses two's complement. */
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#define _GL_INT_TWOS_COMPLEMENT(e) (~ _GL_INT_CONVERT (e, 0) == -1)
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2011-01-09 01:20:28 +00:00
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/* True if the arithmetic type T is signed. */
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2011-05-16 00:51:54 +00:00
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#define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
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/* Return 1 if the integer expression E, after integer promotion, has
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a signed type. E should not have side effects. */
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2011-05-22 21:02:48 +00:00
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#define _GL_INT_SIGNED(e) (_GL_INT_NEGATE_CONVERT (e, 1) < 0)
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2011-01-09 01:20:28 +00:00
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2011-05-16 00:51:54 +00:00
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/* Minimum and maximum values for integer types and expressions. These
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2011-01-09 01:20:28 +00:00
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macros have undefined behavior if T is signed and has padding bits.
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If this is a problem for you, please let us know how to fix it for
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your host. */
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2011-05-16 00:51:54 +00:00
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/* The maximum and minimum values for the integer type T. */
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#define TYPE_MINIMUM(t) \
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((t) (! TYPE_SIGNED (t) \
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? (t) 0 \
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: TYPE_SIGNED_MAGNITUDE (t) \
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? ~ (t) 0 \
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gnulib: import mktime and move-if-change fixes from gnulib
* configure: Regenerate from the following.
2011-01-30 Paul Eggert <eggert@cs.ucla.edu>
mktime: clarify long_int width checking
* lib/mktime.c (long_int_is_wide_enough): Move this assertion to
the top level, to make it clearer that the assumption about
long_int width is being checked. See
<http://lists.gnu.org/archive/html/bug-gnulib/2011-01/msg00554.html>.
2011-01-29 Paul Eggert <eggert@cs.ucla.edu>
TYPE_MAXIMUM: avoid theoretically undefined behavior
* lib/intprops.h (TYPE_MINIMUM, TYPE_MAXIMUM): Do not shift a
negative number, which the C Standard says has undefined behavior.
In practice this is not a problem, but might as well do it by the book.
Reported by Rich Felker and Eric Blake; see
<http://lists.gnu.org/archive/html/bug-gnulib/2011-01/msg00493.html>.
* m4/mktime.m4 (AC_FUNC_MKTIME): Likewise.
* lib/mktime.c (TYPE_MAXIMUM): Redo slightly to match the others.
mktime: #undef mktime before #defining it
* lib/mktime.c (mktime) [DEBUG]: #undef mktime before #defining it.
mktime: systematically normalize tm_isdst comparisons
* lib/mktime.c (isdst_differ): New function.
(__mktime_internal): Use it systematically for all isdst comparisons.
This completes the fix for libc BZ #6723, and removes the need for
normalizing tm_isdst. See
<http://sourceware.org/bugzilla/show_bug.cgi?id=6723>
(not_equal_tm) [DEBUG]: Use isdst_differ here, too.
mktime: fix some integer overflow issues and sidestep the rest
This was prompted by a bug report by Benjamin Lindner for MinGW
<http://lists.gnu.org/archive/html/bug-gnulib/2011-01/msg00472.html>.
His bug is due to signed integer overflow (0 - INT_MIN), and I
I scanned through mktime.c looking for other integer overflow
problems, fixing all the bugs I found.
Although the C Standard says the resulting code is still not safe
in the presence of integer overflow, in practice it should be good
enough for all real-world two's-complement implementations, except
for debugging environments that deliberately trap on integer
overflow (e.g., gcc -ftrapv).
* lib/mktime.c (WRAPV): New macro.
(SHR): Also check that long_int and time_t shift right in the
usual way, before using the fast-but-unportable method.
(TYPE_ONES_COMPLEMENT, TYPE_SIGNED_MAGNITUDE): Remove, no longer
used. The code already assumed two's complement, so there's
no need to test for alternatives. All uses removed.
(TYPE_MAXIMUM): Don't rely here on overflow behavior not defined by
the C standard. Problem reported by Rich Felker in
<http://lists.gnu.org/archive/html/bug-gnulib/2011-01/msg00488.html>.
(twos_complement_arithmetic): Also check long_int and time_t.
(time_t_avg, time_t_add_ok, time_t_int_add_ok): New functions.
(guess_time_tm, ranged_convert, __mktime_internal): Use them.
(__mktime_internal): Avoid integer overflow with unary subtraction
in two instances where -1 - X is an adequate replacement for -X,
since the calculations are approximate.
2011-01-29 Eric Blake <eblake@redhat.com>
mktime: avoid infinite loop
* m4/mktime.m4 (AC_FUNC_MKTIME): Avoid overflow on possibly-signed
type; behavior is still undefined but portable to all known targets.
Reported by Rich Felker.
2011-01-28 Paul Eggert <eggert@cs.ucla.edu>
mktime: avoid problems on NetBSD 5 / i386
* lib/mktime.c (long_int): New type. This works around a problem
on NetBSD 5 / i386, where 'long int' and 'int' are both 32 bits
but time_t is 64 bits, and where I expect the existing code is
wrong in some cases.
(leapyear, ydhms_diff, guess_time_tm, __mktime_internal): Use it.
(ydhms_diff): Bring back the compile-time check for wide-enough
year and yday.
mktime: fix misspelling in comment
* lib/mktime.c (__mktime_internal): Fix misspelling in comment.
This merges all recent glibc changes of importance.
2011-01-28 Ralf Wildenhues <Ralf.Wildenhues@gmx.de>
move-if-change: cope with concurrent mv of identical file.
* move-if-change (CMPPROG): Accept environment
variable as an override for `cmp'.
(usage): Document CMPPROG.
Adjust comparison to drop stdout. Cope with failure of mv if
the target file exists and is identical to the source, for
parallel builds.
Report from H.J. Lu against binutils in PR binutils/12283.
2011-01-30 19:22:02 +00:00
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: ~ TYPE_MAXIMUM (t)))
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2011-05-16 00:51:54 +00:00
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#define TYPE_MAXIMUM(t) \
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((t) (! TYPE_SIGNED (t) \
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? (t) -1 \
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gnulib: import mktime and move-if-change fixes from gnulib
* configure: Regenerate from the following.
2011-01-30 Paul Eggert <eggert@cs.ucla.edu>
mktime: clarify long_int width checking
* lib/mktime.c (long_int_is_wide_enough): Move this assertion to
the top level, to make it clearer that the assumption about
long_int width is being checked. See
<http://lists.gnu.org/archive/html/bug-gnulib/2011-01/msg00554.html>.
2011-01-29 Paul Eggert <eggert@cs.ucla.edu>
TYPE_MAXIMUM: avoid theoretically undefined behavior
* lib/intprops.h (TYPE_MINIMUM, TYPE_MAXIMUM): Do not shift a
negative number, which the C Standard says has undefined behavior.
In practice this is not a problem, but might as well do it by the book.
Reported by Rich Felker and Eric Blake; see
<http://lists.gnu.org/archive/html/bug-gnulib/2011-01/msg00493.html>.
* m4/mktime.m4 (AC_FUNC_MKTIME): Likewise.
* lib/mktime.c (TYPE_MAXIMUM): Redo slightly to match the others.
mktime: #undef mktime before #defining it
* lib/mktime.c (mktime) [DEBUG]: #undef mktime before #defining it.
mktime: systematically normalize tm_isdst comparisons
* lib/mktime.c (isdst_differ): New function.
(__mktime_internal): Use it systematically for all isdst comparisons.
This completes the fix for libc BZ #6723, and removes the need for
normalizing tm_isdst. See
<http://sourceware.org/bugzilla/show_bug.cgi?id=6723>
(not_equal_tm) [DEBUG]: Use isdst_differ here, too.
mktime: fix some integer overflow issues and sidestep the rest
This was prompted by a bug report by Benjamin Lindner for MinGW
<http://lists.gnu.org/archive/html/bug-gnulib/2011-01/msg00472.html>.
His bug is due to signed integer overflow (0 - INT_MIN), and I
I scanned through mktime.c looking for other integer overflow
problems, fixing all the bugs I found.
Although the C Standard says the resulting code is still not safe
in the presence of integer overflow, in practice it should be good
enough for all real-world two's-complement implementations, except
for debugging environments that deliberately trap on integer
overflow (e.g., gcc -ftrapv).
* lib/mktime.c (WRAPV): New macro.
(SHR): Also check that long_int and time_t shift right in the
usual way, before using the fast-but-unportable method.
(TYPE_ONES_COMPLEMENT, TYPE_SIGNED_MAGNITUDE): Remove, no longer
used. The code already assumed two's complement, so there's
no need to test for alternatives. All uses removed.
(TYPE_MAXIMUM): Don't rely here on overflow behavior not defined by
the C standard. Problem reported by Rich Felker in
<http://lists.gnu.org/archive/html/bug-gnulib/2011-01/msg00488.html>.
(twos_complement_arithmetic): Also check long_int and time_t.
(time_t_avg, time_t_add_ok, time_t_int_add_ok): New functions.
(guess_time_tm, ranged_convert, __mktime_internal): Use them.
(__mktime_internal): Avoid integer overflow with unary subtraction
in two instances where -1 - X is an adequate replacement for -X,
since the calculations are approximate.
2011-01-29 Eric Blake <eblake@redhat.com>
mktime: avoid infinite loop
* m4/mktime.m4 (AC_FUNC_MKTIME): Avoid overflow on possibly-signed
type; behavior is still undefined but portable to all known targets.
Reported by Rich Felker.
2011-01-28 Paul Eggert <eggert@cs.ucla.edu>
mktime: avoid problems on NetBSD 5 / i386
* lib/mktime.c (long_int): New type. This works around a problem
on NetBSD 5 / i386, where 'long int' and 'int' are both 32 bits
but time_t is 64 bits, and where I expect the existing code is
wrong in some cases.
(leapyear, ydhms_diff, guess_time_tm, __mktime_internal): Use it.
(ydhms_diff): Bring back the compile-time check for wide-enough
year and yday.
mktime: fix misspelling in comment
* lib/mktime.c (__mktime_internal): Fix misspelling in comment.
This merges all recent glibc changes of importance.
2011-01-28 Ralf Wildenhues <Ralf.Wildenhues@gmx.de>
move-if-change: cope with concurrent mv of identical file.
* move-if-change (CMPPROG): Accept environment
variable as an override for `cmp'.
(usage): Document CMPPROG.
Adjust comparison to drop stdout. Cope with failure of mv if
the target file exists and is identical to the source, for
parallel builds.
Report from H.J. Lu against binutils in PR binutils/12283.
2011-01-30 19:22:02 +00:00
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: ((((t) 1 << (sizeof (t) * CHAR_BIT - 2)) - 1) * 2 + 1)))
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2011-01-09 01:20:28 +00:00
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2011-05-16 00:51:54 +00:00
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/* The maximum and minimum values for the type of the expression E,
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after integer promotion. E should not have side effects. */
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#define _GL_INT_MINIMUM(e) \
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(_GL_INT_SIGNED (e) \
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? - _GL_INT_TWOS_COMPLEMENT (e) - _GL_SIGNED_INT_MAXIMUM (e) \
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: _GL_INT_CONVERT (e, 0))
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#define _GL_INT_MAXIMUM(e) \
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(_GL_INT_SIGNED (e) \
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? _GL_SIGNED_INT_MAXIMUM (e) \
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2011-05-22 21:02:48 +00:00
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: _GL_INT_NEGATE_CONVERT (e, 1))
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2011-05-16 00:51:54 +00:00
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#define _GL_SIGNED_INT_MAXIMUM(e) \
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(((_GL_INT_CONVERT (e, 1) << (sizeof ((e) + 0) * CHAR_BIT - 2)) - 1) * 2 + 1)
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/* Return 1 if the __typeof__ keyword works. This could be done by
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'configure', but for now it's easier to do it by hand. */
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#if 2 <= __GNUC__ || 0x5110 <= __SUNPRO_C
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# define _GL_HAVE___TYPEOF__ 1
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#else
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# define _GL_HAVE___TYPEOF__ 0
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#endif
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/* Return 1 if the integer type or expression T might be signed. Return 0
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if it is definitely unsigned. This macro does not evaluate its argument,
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and expands to an integer constant expression. */
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#if _GL_HAVE___TYPEOF__
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# define _GL_SIGNED_TYPE_OR_EXPR(t) TYPE_SIGNED (__typeof__ (t))
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#else
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# define _GL_SIGNED_TYPE_OR_EXPR(t) 1
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#endif
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2011-01-09 01:20:28 +00:00
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/* Bound on length of the string representing an unsigned integer
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value representable in B bits. log10 (2.0) < 146/485. The
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smallest value of B where this bound is not tight is 2621. */
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2011-05-16 00:51:54 +00:00
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#define INT_BITS_STRLEN_BOUND(b) (((b) * 146 + 484) / 485)
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2011-01-09 01:20:28 +00:00
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/* Bound on length of the string representing an integer type or expression T.
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Subtract 1 for the sign bit if T is signed, and then add 1 more for
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2011-05-16 00:51:54 +00:00
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a minus sign if needed.
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Because _GL_SIGNED_TYPE_OR_EXPR sometimes returns 0 when its argument is
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signed, this macro may overestimate the true bound by one byte when
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applied to unsigned types of size 2, 4, 16, ... bytes. */
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#define INT_STRLEN_BOUND(t) \
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(INT_BITS_STRLEN_BOUND (sizeof (t) * CHAR_BIT \
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- _GL_SIGNED_TYPE_OR_EXPR (t)) \
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+ _GL_SIGNED_TYPE_OR_EXPR (t))
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2011-01-09 01:20:28 +00:00
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/* Bound on buffer size needed to represent an integer type or expression T,
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including the terminating null. */
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2011-05-16 00:51:54 +00:00
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#define INT_BUFSIZE_BOUND(t) (INT_STRLEN_BOUND (t) + 1)
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/* Range overflow checks.
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The INT_<op>_RANGE_OVERFLOW macros return 1 if the corresponding C
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operators might not yield numerically correct answers due to
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arithmetic overflow. They do not rely on undefined or
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implementation-defined behavior. Their implementations are simple
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and straightforward, but they are a bit harder to use than the
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INT_<op>_OVERFLOW macros described below.
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Example usage:
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long int i = ...;
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long int j = ...;
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if (INT_MULTIPLY_RANGE_OVERFLOW (i, j, LONG_MIN, LONG_MAX))
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printf ("multiply would overflow");
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else
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printf ("product is %ld", i * j);
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Restrictions on *_RANGE_OVERFLOW macros:
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These macros do not check for all possible numerical problems or
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undefined or unspecified behavior: they do not check for division
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by zero, for bad shift counts, or for shifting negative numbers.
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These macros may evaluate their arguments zero or multiple times,
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so the arguments should not have side effects. The arithmetic
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arguments (including the MIN and MAX arguments) must be of the same
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integer type after the usual arithmetic conversions, and the type
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must have minimum value MIN and maximum MAX. Unsigned types should
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use a zero MIN of the proper type.
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These macros are tuned for constant MIN and MAX. For commutative
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operations such as A + B, they are also tuned for constant B. */
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/* Return 1 if A + B would overflow in [MIN,MAX] arithmetic.
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See above for restrictions. */
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#define INT_ADD_RANGE_OVERFLOW(a, b, min, max) \
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((b) < 0 \
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? (a) < (min) - (b) \
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: (max) - (b) < (a))
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/* Return 1 if A - B would overflow in [MIN,MAX] arithmetic.
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See above for restrictions. */
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#define INT_SUBTRACT_RANGE_OVERFLOW(a, b, min, max) \
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((b) < 0 \
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? (max) + (b) < (a) \
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: (a) < (min) + (b))
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/* Return 1 if - A would overflow in [MIN,MAX] arithmetic.
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See above for restrictions. */
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#define INT_NEGATE_RANGE_OVERFLOW(a, min, max) \
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((min) < 0 \
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? (a) < - (max) \
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: 0 < (a))
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/* Return 1 if A * B would overflow in [MIN,MAX] arithmetic.
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2011-05-22 21:02:48 +00:00
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See above for restrictions. Avoid && and || as they tickle
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bugs in Sun C 5.11 2010/08/13 and other compilers; see
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<http://lists.gnu.org/archive/html/bug-gnulib/2011-05/msg00401.html>. */
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2011-05-16 00:51:54 +00:00
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#define INT_MULTIPLY_RANGE_OVERFLOW(a, b, min, max) \
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((b) < 0 \
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? ((a) < 0 \
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? (a) < (max) / (b) \
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2011-05-22 21:02:48 +00:00
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: (b) == -1 \
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? 0 \
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: (min) / (b) < (a)) \
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: (b) == 0 \
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? 0 \
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: ((a) < 0 \
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? (a) < (min) / (b) \
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: (max) / (b) < (a)))
|
2011-05-16 00:51:54 +00:00
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/* Return 1 if A / B would overflow in [MIN,MAX] arithmetic.
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See above for restrictions. Do not check for division by zero. */
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#define INT_DIVIDE_RANGE_OVERFLOW(a, b, min, max) \
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((min) < 0 && (b) == -1 && (a) < - (max))
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/* Return 1 if A % B would overflow in [MIN,MAX] arithmetic.
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See above for restrictions. Do not check for division by zero.
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Mathematically, % should never overflow, but on x86-like hosts
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INT_MIN % -1 traps, and the C standard permits this, so treat this
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|
as an overflow too. */
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#define INT_REMAINDER_RANGE_OVERFLOW(a, b, min, max) \
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INT_DIVIDE_RANGE_OVERFLOW (a, b, min, max)
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/* Return 1 if A << B would overflow in [MIN,MAX] arithmetic.
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See above for restrictions. Here, MIN and MAX are for A only, and B need
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not be of the same type as the other arguments. The C standard says that
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behavior is undefined for shifts unless 0 <= B < wordwidth, and that when
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A is negative then A << B has undefined behavior and A >> B has
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implementation-defined behavior, but do not check these other
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restrictions. */
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#define INT_LEFT_SHIFT_RANGE_OVERFLOW(a, b, min, max) \
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((a) < 0 \
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? (a) < (min) >> (b) \
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: (max) >> (b) < (a))
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/* The _GL*_OVERFLOW macros have the same restrictions as the
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*_RANGE_OVERFLOW macros, except that they do not assume that operands
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(e.g., A and B) have the same type as MIN and MAX. Instead, they assume
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that the result (e.g., A + B) has that type. */
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#define _GL_ADD_OVERFLOW(a, b, min, max) \
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((min) < 0 ? INT_ADD_RANGE_OVERFLOW (a, b, min, max) \
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: (a) < 0 ? (b) <= (a) + (b) \
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: (b) < 0 ? (a) <= (a) + (b) \
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: (a) + (b) < (b))
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#define _GL_SUBTRACT_OVERFLOW(a, b, min, max) \
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((min) < 0 ? INT_SUBTRACT_RANGE_OVERFLOW (a, b, min, max) \
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: (a) < 0 ? 1 \
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: (b) < 0 ? (a) - (b) <= (a) \
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: (a) < (b))
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#define _GL_MULTIPLY_OVERFLOW(a, b, min, max) \
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(((min) == 0 && (((a) < 0 && 0 < (b)) || ((b) < 0 && 0 < (a)))) \
|
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|| INT_MULTIPLY_RANGE_OVERFLOW (a, b, min, max))
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|
#define _GL_DIVIDE_OVERFLOW(a, b, min, max) \
|
2011-05-22 21:02:48 +00:00
|
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((min) < 0 ? (b) == _GL_INT_NEGATE_CONVERT (min, 1) && (a) < - (max) \
|
2011-05-16 00:51:54 +00:00
|
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: (a) < 0 ? (b) <= (a) + (b) - 1 \
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|
: (b) < 0 && (a) + (b) <= (a))
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|
|
#define _GL_REMAINDER_OVERFLOW(a, b, min, max) \
|
2011-05-22 21:02:48 +00:00
|
|
|
((min) < 0 ? (b) == _GL_INT_NEGATE_CONVERT (min, 1) && (a) < - (max) \
|
2011-05-16 00:51:54 +00:00
|
|
|
: (a) < 0 ? (a) % (b) != ((max) - (b) + 1) % (b) \
|
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|
|
: (b) < 0 && ! _GL_UNSIGNED_NEG_MULTIPLE (a, b, max))
|
|
|
|
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|
/* Return a nonzero value if A is a mathematical multiple of B, where
|
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|
|
A is unsigned, B is negative, and MAX is the maximum value of A's
|
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|
|
type. A's type must be the same as (A % B)'s type. Normally (A %
|
|
|
|
-B == 0) suffices, but things get tricky if -B would overflow. */
|
|
|
|
#define _GL_UNSIGNED_NEG_MULTIPLE(a, b, max) \
|
|
|
|
(((b) < -_GL_SIGNED_INT_MAXIMUM (b) \
|
|
|
|
? (_GL_SIGNED_INT_MAXIMUM (b) == (max) \
|
|
|
|
? (a) \
|
|
|
|
: (a) % (_GL_INT_CONVERT (a, _GL_SIGNED_INT_MAXIMUM (b)) + 1)) \
|
|
|
|
: (a) % - (b)) \
|
|
|
|
== 0)
|
|
|
|
|
|
|
|
|
|
|
|
/* Integer overflow checks.
|
|
|
|
|
|
|
|
The INT_<op>_OVERFLOW macros return 1 if the corresponding C operators
|
|
|
|
might not yield numerically correct answers due to arithmetic overflow.
|
|
|
|
They work correctly on all known practical hosts, and do not rely
|
|
|
|
on undefined behavior due to signed arithmetic overflow.
|
|
|
|
|
|
|
|
Example usage:
|
|
|
|
|
|
|
|
long int i = ...;
|
|
|
|
long int j = ...;
|
|
|
|
if (INT_MULTIPLY_OVERFLOW (i, j))
|
|
|
|
printf ("multiply would overflow");
|
|
|
|
else
|
|
|
|
printf ("product is %ld", i * j);
|
|
|
|
|
|
|
|
These macros do not check for all possible numerical problems or
|
|
|
|
undefined or unspecified behavior: they do not check for division
|
|
|
|
by zero, for bad shift counts, or for shifting negative numbers.
|
|
|
|
|
|
|
|
These macros may evaluate their arguments zero or multiple times, so the
|
|
|
|
arguments should not have side effects.
|
|
|
|
|
|
|
|
These macros are tuned for their last argument being a constant.
|
|
|
|
|
|
|
|
Return 1 if the integer expressions A * B, A - B, -A, A * B, A / B,
|
|
|
|
A % B, and A << B would overflow, respectively. */
|
|
|
|
|
|
|
|
#define INT_ADD_OVERFLOW(a, b) \
|
|
|
|
_GL_BINARY_OP_OVERFLOW (a, b, _GL_ADD_OVERFLOW)
|
|
|
|
#define INT_SUBTRACT_OVERFLOW(a, b) \
|
|
|
|
_GL_BINARY_OP_OVERFLOW (a, b, _GL_SUBTRACT_OVERFLOW)
|
|
|
|
#define INT_NEGATE_OVERFLOW(a) \
|
|
|
|
INT_NEGATE_RANGE_OVERFLOW (a, _GL_INT_MINIMUM (a), _GL_INT_MAXIMUM (a))
|
|
|
|
#define INT_MULTIPLY_OVERFLOW(a, b) \
|
|
|
|
_GL_BINARY_OP_OVERFLOW (a, b, _GL_MULTIPLY_OVERFLOW)
|
|
|
|
#define INT_DIVIDE_OVERFLOW(a, b) \
|
|
|
|
_GL_BINARY_OP_OVERFLOW (a, b, _GL_DIVIDE_OVERFLOW)
|
|
|
|
#define INT_REMAINDER_OVERFLOW(a, b) \
|
|
|
|
_GL_BINARY_OP_OVERFLOW (a, b, _GL_REMAINDER_OVERFLOW)
|
|
|
|
#define INT_LEFT_SHIFT_OVERFLOW(a, b) \
|
|
|
|
INT_LEFT_SHIFT_RANGE_OVERFLOW (a, b, \
|
|
|
|
_GL_INT_MINIMUM (a), _GL_INT_MAXIMUM (a))
|
|
|
|
|
|
|
|
/* Return 1 if the expression A <op> B would overflow,
|
|
|
|
where OP_RESULT_OVERFLOW (A, B, MIN, MAX) does the actual test,
|
|
|
|
assuming MIN and MAX are the minimum and maximum for the result type.
|
2011-05-22 21:02:48 +00:00
|
|
|
Arguments should be free of side effects. */
|
2011-05-16 00:51:54 +00:00
|
|
|
#define _GL_BINARY_OP_OVERFLOW(a, b, op_result_overflow) \
|
|
|
|
op_result_overflow (a, b, \
|
2011-05-22 21:02:48 +00:00
|
|
|
_GL_INT_MINIMUM ((b) - (b) + (a)), \
|
|
|
|
_GL_INT_MAXIMUM ((b) - (b) + (a)))
|
2011-01-09 01:20:28 +00:00
|
|
|
|
2011-05-16 00:51:54 +00:00
|
|
|
#endif /* _GL_INTPROPS_H */
|