![[MPFR]](../mpfr100.png){kind=small}
The canard à l'orange release, patch level 5.
MPFR 3.1.5 requires GMP 4.1.0 or higher (GMP 4.2.3 or higher is recommended).
Note: the bug-fix release MPFR 3.1.6 is available. Please upgrade!
Warning! Due to the fact that
TLS support is now detected
automatically, the MPFR build can be incorrect on some
platforms (compiler or system bug). Indeed,
the
TLS implementation of some compilers/platforms is buggy,
and MPFR cannot detect every problem at configure time.
Please run make check
to see if your build is affected.
If you get failures, you should try the --disable-thread-safe
configure option to disable TLS and see if this solves
these failures. But you should not use an MPFR library
with TLS disabled in a multithreaded program (unless
you know what you are doing).
The MPFR 3.1.5 source can be downloaded in the following archive formats:
Each tarball is signed by Vincent Lefèvre. This can be verified using the DSA key ID 980C197698C3739D; this key can be retrieved with:
gpg --recv-keys 980C197698C3739D
or by downloading it from https://www.vinc17.net/pgp.html. The key fingerprint is:
07F3 DBBE CC1A 3960 5078 094D 980C 1976 98C3 739D
The signatures can be verified with:
gpg --verify file.asc
You should check that the key fingerprint matches.
MPFR is also available via third-party packages and ports.
The bugs listed below have been fixed (latest update: 2017-08-01). The patches are distributed under the same license as this version of MPFR, that is, the GNU Lesser General Public License (GNU Lesser GPL), version 3 or later.
The following instructions are for Linux and may be similar for other operating systems. You can apply the patches in several ways:
patch -N -Z -p1 < path_to_patches_filefrom the source directory. The -N option allows the patch command to ignore patches already applied. The -Z option sets the modification time of the patched files from time stamps given in the patch file, thus avoiding the need of some development utilities (such as autoconf); this may generate a
Not setting timewarning for the PATCHES file, but you can safely ignore it. Under Microsoft Windows, in addition to the above options, you may need the --binary option (this depends whether the end-of-lines have been converted when you downloaded the patch file). Also note that the --dry-run option does not work if the cumulative patch has some file listed several times.
svn co svn://scm.gforge.inria.fr/svn/mpfr/branches/3.1 mpfr-3.1(Warning! No authentication is done.) In this case, as said on the Gforge page, you should read the README.dev file for details on how to build MPFR. Also note that the branch may contain additional minor fixes.
With the first two ways, the PATCHES file is modified,
so that one can know what patches have been applied, using the
mpfr_get_patches function. Moreover a suffix is added to
the version string, but note that for practical reasons, not all the
files where the version appears are patched; thus one can also track
applied patches with the MPFR_VERSION_STRING macro (header)
and the mpfr_get_version function (library). However, if
some patches are not applied or if patches are applied in a different
order, then the patch command will fail to update some chunks, so that
the suffix is not always reliable for patches.
Note: These patches are in unified diff format and some vendors' patch commands cannot deal with them; in this case, please use GNU patch (it may already be installed on your system, e.g. as /usr/local/bin/patch or gpatch).
Fixed bugs, with patches:
mpfr_strtofr can return an incorrect
ternary value in the round-to-nearest mode (MPFR_RNDN). As a
consequence, the value can also be incorrect if the current exponent range
is not the maximum one (since the maximum exponent range is used internally
and the ternary value is used to resolve double rounding when reducing the
exponent range to the current one); this can happen only if the value is a
midpoint between 0 and the minimum positive number or the opposite.
This bug is fixed by the strtofr patch,
which also provides a test case.partition_number) for the return value:
int and long types have the same size,
the code assumes wrapping behavior in two's complement. But this is actually
undefined behavior in ISO C, and in practice, a smart
compiler may ignore some tests.errno is no longer set
to EOVERFLOW when supported. This bug is fixed by the
printf-errno patch.setlocale
standard function is used incorrectly. This bug is fixed by the
tsprintf-setlocale patch.unsigned long type
(32-bit ABI or
Microsoft Windows), computations in sin_cos.c
suffer from overflows in high precisions (more than about 1,000,000 bits).
In practice, this introduces an error of up to 2−1019574
approximately, so that the trigonometric functions (mpfr_sin,
mpfr_cos, mpfr_sin_cos, mpfr_tan) and
functions that call them can be very inaccurate (limiting the overall accuracy
to about one million bits for these functions on such platforms). This bug
is fixed by the sincos-overflow patch
(no test cases are provided due to the high precisions needed to reproduce
the bug, but the behavior can be tested with this small
C program sin-tst.c, for instance with the argument
1.0).Moreover, mpfr_urandom has several issues:
Some cleanup concerning thread-safe DLL on Windows
has also been added, in particular to avoid compiler warnings.
Corresponding changeset in the 3.1 branch:
77ffa7c0 (r10917).
Other bugs: See the tracker and the BUGS file.
MPFR 3.1.5 has been successfully compiled and checked on the following platforms: