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Joseph Myers cec7d28af8 Fix ldbl-96 lroundl just below powers of 2 (bug 19071).
The ldbl-96 version of lroundl is incorrect for systems with 64-bit
long when the argument's absolute value is just below a power of 2,
2^32 or more, and rounds up to the next integer; in such cases, it
returns 0.  The problem is incrementing the high part of the mantissa
loses the high bit of the value (which is not an issue for any other
floating-point format, and is handled specially in lround when the bit
corresponding to 0.5 was in the high part rather than the low part).

This patch fixes this in a similar way to that used in llroundl:
storing the high part in an unsigned long variable before incrementing
it, so problems cannot occur in the case when this code is reachable.
I improved test coverage for both lround and llround by making them
use the same test inputs (appropriately conditioned on the size of
long in the lround case) - complete with the same comments, to make
comparison as easy as possible.  (This test coverage improvement was
how I found the lroundl bug.)

Tested for x86_64 and x86.

	[BZ #19071]
	* sysdeps/ieee754/ldbl-96/s_lroundl.c (__lroundl): Use unsigned
	long int variable to store possibly incremented high part of
	mantissa.
	* math/libm-test.inc (lround_test_data): Add tests used for
	llround.  Use [LONG_MAX > 0x7fffffff] consistently as condition
	for tests requiring 64-bit long.  Do not condition tests on
	[TEST_FLOAT] unnecessarily.
	(llround_test_data): Add tests used for lround.  Add another
	expectation for the "inexact" exception.  Do not condition tests
	on [TEST_FLOAT] unnecessarily.
2015-10-05 22:54:50 +00:00
argp
assert
benchtests Add a new benchmark for isinf/isnan/isnormal/isfinite/fpclassify. The test uses 2 arrays with 1024 doubles, one with 99% finite FP numbers (10% zeroes, 10% negative) and 1% inf/NaN, the other with 50% inf, and 50% Nan. 2015-09-18 16:02:38 +01:00
bits
catgets
conf
conform Test for weak undefined symbols in linknamespace.pl. 2015-09-18 00:52:07 +00:00
crypt
csu
ctype
debug
dirent
dlfcn
elf [BZ #17250] Fix static dlopen default library search path 2015-09-25 09:37:12 +01:00
gmon
gnulib
grp Harden putpwent, putgrent, putspent, putspent against injection [BZ #18724] 2015-10-02 11:34:13 +02:00
gshadow Harden putpwent, putgrent, putspent, putspent against injection [BZ #18724] 2015-10-02 11:34:13 +02:00
hesiod
hurd
iconv
iconvdata
include Harden putpwent, putgrent, putspent, putspent against injection [BZ #18724] 2015-10-02 11:34:13 +02:00
inet
intl
io
libidn
libio
locale localedef: improve error message [BZ #16985] 2015-09-11 23:25:06 -04:00
localedata
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mach Add missing __mach_host_self_ symbol in Versions 2015-09-22 02:02:20 +02:00
malloc Use ALIGN_DOWN in systrim. 2015-09-14 15:32:47 -04:00
manual Files open O_WRONLY not supported in fallocate emulation. 2015-09-29 11:32:36 -04:00
math Fix ldbl-96 lroundl just below powers of 2 (bug 19071). 2015-10-05 22:54:50 +00:00
mathvec
misc Use __pthread_setcancelstate in libc.a 2015-09-17 16:38:54 -07:00
nis
nptl Remove ignored symbols from nptl/Versions 2015-09-22 09:32:38 -07:00
nptl_db
nscd
nss Fix i386 build after put*ent hardening changes. 2015-10-02 11:14:19 +00:00
po Update de.po from Translation Project (bug 4404). 2015-09-16 16:51:28 +00:00
posix Use __pthread_setcancelstate in libc.a 2015-09-17 16:38:54 -07:00
pwd Harden putpwent, putgrent, putspent, putspent against injection [BZ #18724] 2015-10-02 11:34:13 +02:00
resolv Fix several build failures with GCC6 due to unused static variables. 2015-09-18 20:42:54 +01:00
resource
rt
scripts
setjmp
shadow Harden putpwent, putgrent, putspent, putspent against injection [BZ #18724] 2015-10-02 11:34:13 +02:00
signal
socket
soft-fp
stdio-common Cleanup a few cases where isinf is used to get the signbit to improve the readability and maintainability and allow inlining. 2015-09-18 21:19:48 +01:00
stdlib Refactor code forcing underflow exceptions. 2015-09-23 22:42:30 +00:00
streams
string Let 'make check subdirs=string' succeed even when it's invoked 2015-09-28 16:55:57 -04:00
sunrpc
sysdeps Fix ldbl-96 lroundl just below powers of 2 (bug 19071). 2015-10-05 22:54:50 +00:00
sysvipc
termios
time Fix BZ #18985 -- out of range data to strftime() causes a segfault 2015-09-26 13:27:48 -07:00
timezone timezone: add a configure flag to disable program install 2015-09-18 19:39:46 -04:00
wcsmbs
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BUGS
ChangeLog Fix ldbl-96 lroundl just below powers of 2 (bug 19071). 2015-10-05 22:54:50 +00:00
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config.h.in Work around powerpc32 integer 0 converting to -0 (bug 887, bug 19049, bug 19050). 2015-10-05 17:46:50 +00:00
config.make.in timezone: add a configure flag to disable program install 2015-09-18 19:39:46 -04:00
configure timezone: add a configure flag to disable program install 2015-09-18 19:39:46 -04:00
configure.ac timezone: add a configure flag to disable program install 2015-09-18 19:39:46 -04:00
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INSTALL timezone: add a configure flag to disable program install 2015-09-18 19:39:46 -04:00
libc-abis
LICENSES
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Makefile Prevent check-local-headers.sh hang. 2015-09-14 09:57:58 -04:00
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NEWS Fix ldbl-96 lroundl just below powers of 2 (bug 19071). 2015-10-05 22:54:50 +00:00
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