Copyright 1999-2019 Free Software Foundation, Inc.
Contributed by the AriC and Caramba projects, INRIA.
This file is part of the GNU MPFR Library.
The GNU MPFR Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 3 of the License, or (at your
option) any later version.
The GNU MPFR Library 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 Lesser General Public
License for more details.
You should have received a copy of the GNU Lesser General Public License
along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see
https://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
Installing GNU MPFR
Note: In case of problem, please read this INSTALL file carefully before
reporting a bug, in particular Section "In case of problem" below. Some
problems are due to bad configuration on the user side (not specific to
0. You first need to install GMP. See <https://gmplib.org/>.
MPFR requires GMP version 5.0.0 or later.
1. Extract the files from the archive.
2. It is strongly advised to apply the latest patches if this has
not been done yet and if patches are available. You can check
on the release page:
which may have additional information. The patches can be applied
with commands like:
patch -N -Z -p1 < allpatches
curl https://www.mpfr.org/mpfr-4.0.2/allpatches | patch -N -Z -p1
(Those instructions are for the GNU patch command, for example
/usr/bin/gpatch on Solaris.)
3. In the MPFR directory, to detect your system, type:
possibly with options (see below, in particular if this step or
one of the following fails). You should also check whether WARNING
lines have been output (such a problem may cause a failure in one
of the following steps).
Note: paths provided in configure options must always be absolute
(relative paths are not supported).
4. To build the library, type:
[optional] if you want to tune MPFR for your specific architecture, see
the section "Tuning MPFR" below. Note that for most common architectures,
MPFR includes some default tuning parameters which should be near from
5. To check the built library (runs the test files), type:
Note: If any test fails, information about this failure can be found in
the tests/test-suite.log file; you should provide this file in your bug
reports (in addition to other useful information, as mentioned later).
If you want the contents of this file to be automatically output in case
of failure, you can set the VERBOSE environment variable to 1 before
running "make check", for instance by typing:
VERBOSE=1 make check
6. [Optional / experimental] Binary distributions may also want to run:
This will check that MPFR does not use GMP internal symbols, which
could yield failures in case of GMP upgrade without a MPFR rebuild.
But note that this is a heuristic and might give false positives or
false negatives. Please report any problem to the MPFR developers.
End users may also be interested in this check, unless they have
allowed GMP internals with configure options (see below).
7. To install it (default "/usr/local" | see "--prefix" option), type:
If you installed MPFR (header and library) in directories that are
not searched by default by the compiler and/or linking tools, then,
like with other libraries, you may need to set up some environment
variables such as C_INCLUDE_PATH (to find the header mpfr.h),
LIBRARY_PATH (to find the library), and if the shared library has
been installed, LD_LIBRARY_PATH (before execution) or LD_RUN_PATH
(before linking); this list is not exhaustive and some environment
variables may be specific to your system. "make install" gives some
instructions; please read them. You can also find more information
in the manuals of your compiler and linker. The MPFR FAQ may also
give some information.
Remember that if you have several MPFR (or GMP) versions installed
(e.g., one with the system, and one, newer, by you), you will not
necessarily get a compilation/linking error if a wrong library is
used (e.g., because LD_LIBRARY_PATH has not been set correctly).
But unexpected results may occur.
Under Mac OS X, if the shared library was not installed and you use
Apple's linker (this is the default), you will also need to provide
the -search_paths_first linker flag ("-Wl,-search_paths_first" when
you link via gcc) to make sure that the right library is selected,
as by default, Apple's linker selects a shared library preferably,
even when it is farther in the library paths. We recall that if a
wrong library is selected due to this behavior, unexpected results
Building the documentation
To build the documentation in various formats, you may first need to
install recent versions of some utilities such as texinfo.
* Type "make info" to produce the documentation in the info format.
* Type "make pdf" to produce the documentation in the PDF format.
* Type "make dvi" to produce the documentation in the DVI format.
* Type "make ps" to produce the documentation in the Postscript format.
* Type "make html" to produce the documentation in the HTML format
(in several pages); if you want only one output HTML file, then
type "makeinfo --html --no-split mpfr.texi" from the doc directory
Building MPFR with internal GMP header files
MPFR built with internal GMP header files is a bit faster, so you may want
to build it with them. Just do this in step 1:
where GMPBUILD is the GMP build directory. The needed header files are:
gmp-impl.h, longlong.h and all the necessary headers to use them, which
may be located either in the GMP source directory or in the GMP build
directory, in case they are different (MPFR takes care of that, as of
Warning: the library obtained in this way may use some internal GMP
symbols, and thus dynamically linking your software with a different
version of GMP might fail, even though it is declared as compatible
by Libtool's versioning system.
[For the current GMP version (6.1.0), a Unix-like OS is required.]
For this, you need to build MPFR with a GMP build directory (see above).
In the GMP build directory, you also need to go into the "tune" subdirectory
and type "make speed". This will build the GMP speed library, which is used
by the MPFR tuning mechanism.
Then go back to the MPFR build directory, go into the "tune" subdirectory and
type "make tune". This will build an optimized file "mparam.h" for your
--prefix=DIR installs MPFR headers and library in DIR/include and
DIR/lib respectively (the default is "/usr/local").
--with-gmp-include=DIR assumes that DIR contains gmp.h
--with-gmp-lib=DIR assumes that DIR contains the GMP library
--with-gmp=DIR assumes that DIR is where you have installed GMP.
same as --with-gmp-lib=DIR/lib
(use either --with-gmp alone or one or both of
Warning! Do not use these options if you have
CPPFLAGS and/or LDFLAGS containing a -I or -L
option with a directory that contains a GMP
header or library file, as these options just
add -I and -L options to CPPFLAGS and LDFLAGS
*after* the ones that are currently declared,
so that DIR will have a lower precedence. Also,
this may not work if DIR is a system directory
(typically /usr or /usr/local); see below.
--with-gmp-build=DIR assumes that DIR contains the GMP build directory,
and enables the use of GMP internals (see above).
Warning! This option and the group of options
--with-gmp are mutually exclusive.
--enable-assert build MPFR with assertions.
--enable-thread-safe build MPFR as thread safe, using compiler-level
Thread Local Storage (TLS). Note: TLS support is
roughly tested by configure. If configure detects
that TLS does not work (because of the compiler,
linker or system libraries), it will output an
error message, telling you to build MPFR without
thread safe. For instance, though Mac OS X uses
GCC, it may not currently support GCC's __thread
--disable-thread-safe build MPFR without TLS. By default, TLS support
is detected automatically, and MPFR is built as
thread safe if supported. However this detection
is only a heuristic: TLS can be detected as
supported while its support is incomplete or
buggy (MPFR tests may fail). In such a case,
this option is useful.
--enable-gmp-internals allows the MPFR build to use GMP's undocumented
functions (not from the public API). Note that
library versioning is not guaranteed to work if
this option is used. Thus it must not be used in
--with-sysroot=DIR Search for dependent libraries within DIR (which
may be useful in cross-compilation). If you use
this option, you need to have Libtool 2.4+ on
the target system. See Libtool 2.4+'s NEWS file.
Technical information can be found at .
Note: By default, the configure script tries to set CC / CFLAGS to GMP's
ones from gmp.h (__GMP_CC / __GMP_CFLAGS) in order to ensure that MPFR is
built with the same ABI as GMP. The reason is that when GMP is built, it
may set CC / CFLAGS to select an ABI that is not the default one in order
to have a better performance. The -pedantic option in GMP's CFLAGS, when
present (which is the case by default), is removed, because the MPFR
build system uses some C extensions (when this script detects that they
are supported) and -pedantic yields too many useless warnings. However,
this setting from GMP is not guaranteed to work as the configure script
does some compiler tests earlier, and a conflict may arise. Also, the
values obtained from GMP may be incorrect for the MPFR build if GMP has
been built on a different machine; in such a case, the user may need to
specify CC / CFLAGS, as explained below.
Moreover, even without --with-gmp-build and --enable-gmp-internals,
MPFR might use some GMP internals by mistake. This would be a bug,
which should be reported to the MPFR developers.
Run "./configure --help" to see the other options (default options
from Autoconf and Automake).
If 'gmp.h' and 'libgmp' do not match
Under some circumstances, the configure script may output a message
'gmp.h' and 'libgmp' seem to have different versions or
we cannot run a program linked with GMP (if you cannot
see the version numbers above). [...]
Even though the configure script does not fail in such a case, this
message most often indicates a real error, which needs to be avoided.
Possible causes are:
* The wanted GMP library does not have the same ABI as the one chosen
to build MPFR. The consequences may be:
- A different GMP library (with the correct ABI) has been found,
but does not have the same version as 'gmp.h'.
- No other GMP libraries have been found (in this case, no version
numbers should be printed above the warning message).
This is incorrect and one of the following steps (make, make check)
will probably fail. GMP (actually gmp.h) now provides CC and CFLAGS
information to select the correct ABI, so that this problem should
no longer occur; but if GMP was provided by a binary package, such
information may not be valid. See the
checking for CC and CFLAGS in gmp.h...
line in the configure output (about the 11th line) and the following
few ones for more information. You may need to reinstall GMP or to
provide your own CC and/or CFLAGS. See also the remaining of this
* A configure option like --with-gmp or --with-gmp-include was used
with a system include directory, e.g. one of the following:
GCC (and possibly other compilers) will ignore such a directive for
include directories (but this rule is not applied for the library
itself!). This means that the library search paths will be reordered
as declared, but the specified include directory will still be near
the end of the include search paths (thus with a low precedence).
This is not a problem if only one GMP version is installed, but
otherwise, a wrong gmp.h may be chosen, so that the versions of
gmp.h and libgmp may not match. The suggestions are the following:
- If you want to use the GMP version under /usr, then you should
uninstall all the other GMP versions (header and library files)
that may be seen in the search paths, in particular those under
- If you want to use the GMP version under /usr/local, then you
should uninstall all the other GMP versions (header and library
files) that may be seen in the search paths, but *NOT* the one
under /usr (the version under /usr is provided by the OS vendor,
and changing/removing anything related to it may break your
system, and /usr should have a lower precedence than /usr/local
To find where GMP versions have been installed:
$ locate libgmp (if you have a locate database)
and if the compiler is GCC:
$ gcc -print-file-name=libgmp.so (under most systems)
$ gcc -print-file-name=libgmp.dylib (under Mac OS X)
and if this does not work, you may try:
$ gcc -print-search-dirs
* An official GCC version was used under Debian GNU/Linux. Problems
may come from the fact that Debian chose a different convention
for library search paths concerning 32-bit and 64-bit libraries.
A possible problem can be, for instance:
[Debian's GCC, correct library path]
$ gcc -print-file-name=libgmp.so
[Official GCC, incorrect library path]
$ gcc-4.3.1 -print-file-name=libgmp.so
The solution: use a GCC provided by Debian or add symbolic links
such as lib64 -> lib (on 64-bit machines) for your library paths.
* The problem may also be temporary and only due to the fact that
libtool could not be used at this time. This is unlikely, though.
In case of problem
First, look for any warning message in the configure output.
Several documents may help you to solve the problem:
* this INSTALL file, in particular information given below;
* the FAQ (either the FAQ.html file distributed with MPFR, or the
on-line version <https://www.mpfr.org/faq.html>, which may be more
* the MPFR web page for this version <https://www.mpfr.org/mpfr-4.0.2/>,
which lists bugs found in this version and provides some patches.
If the "configure" fails, please check that the C compiler and its
options are the same as those for the GMP build (specially the ABI).
You can see the latter with the following command:
grep "^CC\|^CFLAGS" GMPBUILD/Makefile
if the GMP build directory is available. Then type:
./configure <configure options> CC=<C compiler> CFLAGS="<compiler options>"
(quotes are needed when there are spaces or other special characters
in the CC/CFLAGS value) and continue the install. On some platforms,
you should provide further options to match those used by GMP, or set
some environment variables. For instance, see the "Notes on AIX/PowerPC"
Warning! Do NOT use optimization options that can change the semantics
of math operations, such as GCC's -ffast-math or Sun CC's -fast.
Otherwise conversions from/to double's may be incorrect on infinities,
NaN's and signed zeros. Since native FP arithmetic is used in a few
places only, such options would not make MPFR faster anyway.
If some "make check" tests fail, you can try the --disable-thread-safe
configure option (see the configure options above): it has been reported
that some platforms have buggy TLS support. Before trying this option,
you may want to check in the configure output whether MPFR was built
with TLS support; if yes, you will have a line:
checking for TLS support... yes
Alternatively "grep MPFR_USE_THREAD_SAFE config.log" will show that
MPFR_USE_THREAD_SAFE is defined to 1. If it is "no" (or the variable
is not defined), the --disable-thread-safe option would be useless.
Some tests failure may be due to other compiler bugs, in particular
in optimization code. You can try to build MPFR without compiler
optimizations by giving -O0 (letter O, digit 0) in CFLAGS. If the
MPFR tests no longer fail, this was probably due to a compiler bug,
though we cannot exclude a bug in MPFR. You may want to contact us
(see below), possibly after looking at:
On some platforms, try with "gmake" (GNU make) instead of "make".
Problems have been reported with the Tru64 make.
If the configure script reports that gmp.h version and libgmp version
are different, or if the build was OK, but the tests failed to link
with GMP or gave an error like
undefined reference to `__gmp_get_memory_functions'
meaning that the GMP library was not found or a wrong GMP library was
selected by the linker, then your library search paths are probably
not correctly set (some paths are missing or they are specified in an
Such problems commonly occur under some GNU/Linux machines, where the
default header and library search paths may be inconsistent: GCC is
configured to search /usr/local/include and /usr/local/lib by default,
while the dynamic linker ignores /usr/local/lib. If you have a GMP
version installed in /usr (provided by the OS vendor) and a new one
installed in /usr/local, then the header of the new GMP version and
the library of the old GMP version will be used! The best solution
is to make sure that the dynamic linker configuration is consistent
with GCC's behavior, for instance by having /usr/local/lib in
/etc/ld.so.conf or in some file from /etc/ld.so.conf.d (as Debian
did: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=395177). See
also https://gcc.gnu.org/ml/gcc-help/2010-01/msg00171.html for more
information. Alternatively you can use:
* environment variables. This may sometimes be necessary. If DIR
is the installation directory of GMP, add DIR/include to your
CPATH or C_INCLUDE_PATH (for compilers other than GCC, please
check the manual of your compiler), and add DIR/lib to your
LIBRARY_PATH and LD_LIBRARY_PATH (and/or LD_RUN_PATH);
* --with-gmp* configure options (described above), e.g.
--with-gmp=/opt/local (to use /opt/local/include for headers and
/opt/local/lib for libraries), but other software that uses GMP
and/or MPFR will need correct paths too, and environment variables
allow one to set such search paths in a global way.
Note about "--with-gmp=/usr/local". This option may appear to
solve the above inconsistency problem, but does not work as you
expect. Indeed it affects the library search path, in particular,
the one used by the dynamic linker (thus adding the missing
/usr/local/lib directory as wanted), but since /usr/local/include
is a "standard system include directory" for GCC, the include
search patch is not changed; this is often not a problem in this
particular case because usually, /usr/local/include is already
last in the include search patch, but this may fail under some
occasions and may trigger obscure errors.
For instance, under Unix, where paths are separated by a colon:
* With POSIX sh-compatible shells (e.g. sh, ksh, bash, zsh):
* With csh or tcsh:
setenv C_INCLUDE_PATH "/usr/local/include:/other/path/include"
setenv LIBRARY_PATH "/usr/local/lib:/other/path/lib"
setenv LD_LIBRARY_PATH "$LIBRARY_PATH"
If almost all the tests fail and the messages in the test-suite.log file
(or in the output, when running individual tests from the command line)
start with a line of the form:
Incorrect MPFR version! (xxx header vs yyy library)
then this means that an installed MPFR version is tested instead of the
one that has just been built. This is probably not a bug in MPFR, but a
problem caused by the user or system configuration (particular options,
environment variables, etc.) or a bug in the toolchain. In particular,
if LD_LIBRARY_PATH overrides the run path (set up by libtool) and an
installed ABI-compatible version of MPFR is in a directory listed in
the LD_LIBRARY_PATH search path, then this will break. An example with
If you can't solve your problem, you should contact us via the MPFR
mailing-list <firstname.lastname@example.org>, indicating the machine and operating system
used (uname -a), the compiler and version used (gcc -v if you use gcc),
the configure options used if any (including variables such as CC and
CFLAGS), the version of GMP and MPFR used, and a description of the
problem encountered, in particular the tests/test-suite.log file if
"make check" failed. Please send us also the log of the "configure"
Notes about ABI
On 64-bit computers, it may happen that the default ABI (Application Binary
Interface) chosen by MPFR does not correspond to the default one chosen by
In particular, this kind of message may indicate the problem:
/usr/bin/ld: skipping incompatible mpfr/src/.libs/libmpfr.a when searching for -lmpfr
In fact, since MPFR relies on GMP, it uses the same ABI as GMP.
To be sure that your program compiles and links correctly, use the same
compiler flags as MPFR does (look for CFLAGS in config.log).
You might also recompile GMP with a different ABI, with for example
Notes on Mac OS X
If you get an error of the form
ld: pointer in read-only segment not allowed in slidable image...
this can mean that the link is done against a static (GMP) library.
In such a case, you should configure MPFR with --disable-shared to
disable the build of the shared library.
Notes on FreeBSD 4.3
FreeBSD 4.3 is provided with an incorrect <float.h> header file, and
MPFR tests related to long double's may fail. If you cannot upgrade
the system, you can still use MPFR with FreeBSD 4.3, but you should
not use conversions with the long double type.
Notes on AIX/PowerPC
The following has been tested on AIX 7.1.3 (gcc111.fsffrance.org)
with gcc 4.8.1 and GMP 6.1.0.
If GMP was built with the 64-bit ABI, before building and testing MPFR,
you should set the OBJECT_MODE environment variable to 64, e.g., with:
(in a sh-compatible shell). Alternatively add the following to the configure
line: AR="ar -X64" NM="nm -B -X64".
Notes on Solaris
Do not put a -R<dir> option in the LD_OPTIONS environment variable, at least
if the directory <dir> can contain an MPFR library. Otherwise this MPFR
library may be chosen for the tests (make check) instead of the one that has
just been built, in which case, either you will get errors due to unmatched
versions or this problem may remain undetected. The reason is that this
option will appear before the -R options added by libtool, such as the one
to the src/.libs directory containing the MPFR library that has just been
built, and will have the precedence.
MPFR for use with Windows Applications
There are several ways of building MPFR on Windows, the most appropriate
approach depending on how you intend to use the resulting libraries.
a. Using MinGW
1 - We advise to use MinGW (http://www.mingw.org/ for 32-bit, and
https://sourceforge.net/projects/mingw-w64/ for 32- and 64-bit),
which is simpler and less demanding than Cygwin. Contrary to Cygwin,
it also provides native Windows code.
If you also use MSYS, you should use "make" for MSYS instead of
the "make" utility from MinGW-W64 or from GCC, which causes the
libtool: warning: libobj name 'extract.Tpo -c -o extract.lo extract.lo'
may not contain shell special characters.
rm: unknown option -- c
References about this issue and solution:
2 - If you just want to make a binary with gcc, there is nothing to do:
GMP, MPFR and the program compile exactly as under Linux. (It is
recommended to pass --build=xxx-yyy-mingw64 to the GMP configure command,
or --build=xxx with xxx containing mingw.)
3 - To avoid using the Microsoft runtime (which might not be conform to ISO C),
you can use the MinGW runtime package (which is an integral part of MinGW).
For example, with MinGW versions 3.15 and later you can get an
ISO-compliant printf() if you compile your application with either
'-ansi', '-posix' or '-D__USE_MINGW_ANSI_STDIO'. In order to have the
MPFR formatted output functions based on ISO-compliant printf(), you
need to compile GMP (not MPFR) with CC="gcc -D__USE_MINGW_ANSI_STDIO"
(since the standard printf modifiers %e, %Ld and %td are passed to GMP).
Not doing so may result in failures of some of the printf-related tests.
For instance, the following error on some Windows machine has been
Error in mpfr_vsprintf (s, "%e", ...);
FAIL tsprintf.exe (exit status: 1)
The cause is that here the C functions vsnprintf and vsprintf used
internally in GMP do not produce the same output:
Building MPFR with -D__USE_MINGW_ANSI_STDIO is currently useless except
for some error messages in the test suite.
b. Using Cygwin
This build should be similar to that for MinGW except that the resulting
library depends on the Cygwin DLL and cannot therefore be used with
Visual Studio as with MinGW. Indeed, the binaries compiled with Cygwin
require a dynamic library (cygwin.dll) to work; there is a Cygwin option
-mno-cygwin to build native code, but it may require some non-portable tricks.
In case of failure, you may need to pass LDFLAGS='-shared-libgcc' at the
end of the configure line due to a bug in GCC. Otherwise, if threading
support is not needed, you can configure MPFR with --disable-thread-safe.
c. Using Microsoft Visual C++ and Intel C++ Compilers
Static and dynamic MPFR libraries for the 32- and 64-bit versions of
Windows can be built with Microsoft Visual Studio 2015 using the
Microsoft Visual C++ compiler, see:
The Intel C++ compiler provided as a part of Intel Parallel Studio XE
can also be used:
The relevant build projects are available here: