[INSTALL] Reverted incorrect changeset r6870.

git-svn-id: svn://scm.gforge.inria.fr/svn/mpfr/trunk@6872 280ebfd0-de03-0410-8827-d642c229c3f4

1 files changed, 355 insertions, 337 deletions

diff --git a/INSTALL b/INSTALL
index 7d1c323be..29a0fb61f 100644
--- a/INSTALL
+++ b/INSTALL
@@ -1,365 +1,383 @@
-Installation Instructions
-*************************
-
-Copyright (C) 1994, 1995, 1996, 1999, 2000, 2001, 2002, 2004, 2005,
-2006, 2007, 2008, 2009 Free Software Foundation, Inc.
-
-   Copying and distribution of this file, with or without modification,
-are permitted in any medium without royalty provided the copyright
-notice and this notice are preserved.  This file is offered as-is,
-without warranty of any kind.
-
-Basic Installation
-==================
-
-   Briefly, the shell commands `./configure; make; make install' should
-configure, build, and install this package.  The following
-more-detailed instructions are generic; see the `README' file for
-instructions specific to this package.  Some packages provide this
-`INSTALL' file but do not implement all of the features documented
-below.  The lack of an optional feature in a given package is not
-necessarily a bug.  More recommendations for GNU packages can be found
-in *note Makefile Conventions: (standards)Makefile Conventions.
-
-   The `configure' shell script attempts to guess correct values for
-various system-dependent variables used during compilation.  It uses
-those values to create a `Makefile' in each directory of the package.
-It may also create one or more `.h' files containing system-dependent
-definitions.  Finally, it creates a shell script `config.status' that
-you can run in the future to recreate the current configuration, and a
-file `config.log' containing compiler output (useful mainly for
-debugging `configure').
-
-   It can also use an optional file (typically called `config.cache'
-and enabled with `--cache-file=config.cache' or simply `-C') that saves
-the results of its tests to speed up reconfiguring.  Caching is
-disabled by default to prevent problems with accidental use of stale
-cache files.
-
-   If you need to do unusual things to compile the package, please try
-to figure out how `configure' could check whether to do them, and mail
-diffs or instructions to the address given in the `README' so they can
-be considered for the next release.  If you are using the cache, and at
-some point `config.cache' contains results you don't want to keep, you
-may remove or edit it.
-
-   The file `configure.ac' (or `configure.in') is used to create
-`configure' by a program called `autoconf'.  You need `configure.ac' if
-you want to change it or regenerate `configure' using a newer version
-of `autoconf'.
-
-   The simplest way to compile this package is:
-
-  1. `cd' to the directory containing the package's source code and type
-     `./configure' to configure the package for your system.
-
-     Running `configure' might take a while.  While running, it prints
-     some messages telling which features it is checking for.
-
-  2. Type `make' to compile the package.
-
-  3. Optionally, type `make check' to run any self-tests that come with
-     the package, generally using the just-built uninstalled binaries.
-
-  4. Type `make install' to install the programs and any data files and
-     documentation.  When installing into a prefix owned by root, it is
-     recommended that the package be configured and built as a regular
-     user, and only the `make install' phase executed with root
-     privileges.
-
-  5. Optionally, type `make installcheck' to repeat any self-tests, but
-     this time using the binaries in their final installed location.
-     This target does not install anything.  Running this target as a
-     regular user, particularly if the prior `make install' required
-     root privileges, verifies that the installation completed
-     correctly.
-
-  6. You can remove the program binaries and object files from the
-     source code directory by typing `make clean'.  To also remove the
-     files that `configure' created (so you can compile the package for
-     a different kind of computer), type `make distclean'.  There is
-     also a `make maintainer-clean' target, but that is intended mainly
-     for the package's developers.  If you use it, you may have to get
-     all sorts of other programs in order to regenerate files that came
-     with the distribution.
-
-  7. Often, you can also type `make uninstall' to remove the installed
-     files again.  In practice, not all packages have tested that
-     uninstallation works correctly, even though it is required by the
-     GNU Coding Standards.
-
-  8. Some packages, particularly those that use Automake, provide `make
-     distcheck', which can by used by developers to test that all other
-     targets like `make install' and `make uninstall' work correctly.
-     This target is generally not run by end users.
-
-Compilers and Options
-=====================
-
-   Some systems require unusual options for compilation or linking that
-the `configure' script does not know about.  Run `./configure --help'
-for details on some of the pertinent environment variables.
-
-   You can give `configure' initial values for configuration parameters
-by setting variables in the command line or in the environment.  Here
-is an example:
-
-     ./configure CC=c99 CFLAGS=-g LIBS=-lposix
-
-   *Note Defining Variables::, for more details.
-
-Compiling For Multiple Architectures
-====================================
-
-   You can compile the package for more than one kind of computer at the
-same time, by placing the object files for each architecture in their
-own directory.  To do this, you can use GNU `make'.  `cd' to the
-directory where you want the object files and executables to go and run
-the `configure' script.  `configure' automatically checks for the
-source code in the directory that `configure' is in and in `..'.  This
-is known as a "VPATH" build.
-
-   With a non-GNU `make', it is safer to compile the package for one
-architecture at a time in the source code directory.  After you have
-installed the package for one architecture, use `make distclean' before
-reconfiguring for another architecture.
-
-   On MacOS X 10.5 and later systems, you can create libraries and
-executables that work on multiple system types--known as "fat" or
-"universal" binaries--by specifying multiple `-arch' options to the
-compiler but only a single `-arch' option to the preprocessor.  Like
-this:
-
-     ./configure CC="gcc -arch i386 -arch x86_64 -arch ppc -arch ppc64" \
-                 CXX="g++ -arch i386 -arch x86_64 -arch ppc -arch ppc64" \
-                 CPP="gcc -E" CXXCPP="g++ -E"
-
-   This is not guaranteed to produce working output in all cases, you
-may have to build one architecture at a time and combine the results
-using the `lipo' tool if you have problems.
-
-Installation Names
-==================
-
-   By default, `make install' installs the package's commands under
-`/usr/local/bin', include files under `/usr/local/include', etc.  You
-can specify an installation prefix other than `/usr/local' by giving
-`configure' the option `--prefix=PREFIX', where PREFIX must be an
-absolute file name.
-
-   You can specify separate installation prefixes for
-architecture-specific files and architecture-independent files.  If you
-pass the option `--exec-prefix=PREFIX' to `configure', the package uses
-PREFIX as the prefix for installing programs and libraries.
-Documentation and other data files still use the regular prefix.
-
-   In addition, if you use an unusual directory layout you can give
-options like `--bindir=DIR' to specify different values for particular
-kinds of files.  Run `configure --help' for a list of the directories
-you can set and what kinds of files go in them.  In general, the
-default for these options is expressed in terms of `${prefix}', so that
-specifying just `--prefix' will affect all of the other directory
-specifications that were not explicitly provided.
-
-   The most portable way to affect installation locations is to pass the
-correct locations to `configure'; however, many packages provide one or
-both of the following shortcuts of passing variable assignments to the
-`make install' command line to change installation locations without
-having to reconfigure or recompile.
-
-   The first method involves providing an override variable for each
-affected directory.  For example, `make install
-prefix=/alternate/directory' will choose an alternate location for all
-directory configuration variables that were expressed in terms of
-`${prefix}'.  Any directories that were specified during `configure',
-but not in terms of `${prefix}', must each be overridden at install
-time for the entire installation to be relocated.  The approach of
-makefile variable overrides for each directory variable is required by
-the GNU Coding Standards, and ideally causes no recompilation.
-However, some platforms have known limitations with the semantics of
-shared libraries that end up requiring recompilation when using this
-method, particularly noticeable in packages that use GNU Libtool.
-
-   The second method involves providing the `DESTDIR' variable.  For
-example, `make install DESTDIR=/alternate/directory' will prepend
-`/alternate/directory' before all installation names.  The approach of
-`DESTDIR' overrides is not required by the GNU Coding Standards, and
-does not work on platforms that have drive letters.  On the other hand,
-it does better at avoiding recompilation issues, and works well even
-when some directory options were not specified in terms of `${prefix}'
-at `configure' time.
-
-Optional Features
-=================
-
-   If the package supports it, you can cause programs to be installed
-with an extra prefix or suffix on their names by giving `configure' the
-option `--program-prefix=PREFIX' or `--program-suffix=SUFFIX'.
-
-   Some packages pay attention to `--enable-FEATURE' options to
-`configure', where FEATURE indicates an optional part of the package.
-They may also pay attention to `--with-PACKAGE' options, where PACKAGE
-is something like `gnu-as' or `x' (for the X Window System).  The
-`README' should mention any `--enable-' and `--with-' options that the
-package recognizes.
-
-   For packages that use the X Window System, `configure' can usually
-find the X include and library files automatically, but if it doesn't,
-you can use the `configure' options `--x-includes=DIR' and
-`--x-libraries=DIR' to specify their locations.
-
-   Some packages offer the ability to configure how verbose the
-execution of `make' will be.  For these packages, running `./configure
---enable-silent-rules' sets the default to minimal output, which can be
-overridden with `make V=1'; while running `./configure
---disable-silent-rules' sets the default to verbose, which can be
-overridden with `make V=0'.
-
-Particular systems
-==================
-
-   On HP-UX, the default C compiler is not ANSI C compatible.  If GNU
-CC is not installed, it is recommended to use the following options in
-order to use an ANSI C compiler:
-
-     ./configure CC="cc -Ae -D_XOPEN_SOURCE=500"
-
-and if that doesn't work, install pre-built binaries of GCC for HP-UX.
-
-   On OSF/1 a.k.a. Tru64, some versions of the default C compiler cannot
-parse its `<wchar.h>' header file.  The option `-nodtk' can be used as
-a workaround.  If GNU CC is not installed, it is therefore recommended
-to try
-
-     ./configure CC="cc"
-
-and if that doesn't work, try
-
-     ./configure CC="cc -nodtk"
-
-   On Solaris, don't put `/usr/ucb' early in your `PATH'.  This
-directory contains several dysfunctional programs; working variants of
-these programs are available in `/usr/bin'.  So, if you need `/usr/ucb'
-in your `PATH', put it _after_ `/usr/bin'.
-
-   On Haiku, software installed for all users goes in `/boot/common',
-not `/usr/local'.  It is recommended to use the following options:
-
-     ./configure --prefix=/boot/common
-
-Specifying the System Type
+Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
+Contributed by the Arenaire and Cacao 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
+http://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
+MPFR).
+
+0. You first need to install GMP. See <http://www.gnu.org/software/gmp/>.
+   MPFR requires GMP version 4.1 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), e.g.
+     wget http://www.mpfr.org/mpfr-3.0.0/patches
+     patch -N -Z -p1 < patches
+   or
+     curl http://www.mpfr.org/mpfr-3.0.0/patches | 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:
+     ./configure
+   possibly with options (see below, in particular if this step or
+   one of the following fails).
+   Note: paths provided in configure options must always be absolute
+   (relative paths are not supported).
+
+4. To build the library, type:
+     make
+
+5. To check the built library (runs the test files), type:
+     make check
+
+6. To install it (default "/usr/local" | see "--prefix" option), type:
+     make install
+
+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
+may occur.
+
+
+Building the documentation
 ==========================
 
-   There may be some features `configure' cannot figure out
-automatically, but needs to determine by the type of machine the package
-will run on.  Usually, assuming the package is built to be run on the
-_same_ architectures, `configure' can figure that out, but if it prints
-a message saying it cannot guess the machine type, give it the
-`--build=TYPE' option.  TYPE can either be a short name for the system
-type, such as `sun4', or a canonical name which has the form:
+To build the documentation in various formats, you may first need to
+install recent versions of some utilities such as texinfo.
 
-     CPU-COMPANY-SYSTEM
+* Type "make info" to produce the documentation in the info format.
 
-where SYSTEM can have one of these forms:
+* Type "make pdf" to produce the documentation in the PDF format.
 
-     OS
-     KERNEL-OS
+* Type "make dvi" to produce the documentation in the DVI format.
 
-   See the file `config.sub' for the possible values of each field.  If
-`config.sub' isn't included in this package, then this package doesn't
-need to know the machine type.
+* Type "make ps" to produce the documentation in the Postscript format.
 
-   If you are _building_ compiler tools for cross-compiling, you should
-use the option `--target=TYPE' to select the type of system they will
-produce code for.
+* 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" instead.
 
-   If you want to _use_ a cross compiler, that generates code for a
-platform different from the build platform, you should specify the
-"host" platform (i.e., that on which the generated programs will
-eventually be run) with `--host=TYPE'.
 
-Sharing Defaults
-================
+Building MPFR with internal GMP header files
+============================================
 
-   If you want to set default values for `configure' scripts to share,
-you can create a site shell script called `config.site' that gives
-default values for variables like `CC', `cache_file', and `prefix'.
-`configure' looks for `PREFIX/share/config.site' if it exists, then
-`PREFIX/etc/config.site' if it exists.  Or, you can set the
-`CONFIG_SITE' environment variable to the location of the site script.
-A warning: not all `configure' scripts look for a site script.
+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:
 
-Defining Variables
-==================
+  ./configure --with-gmp-build=GMPBUILD
 
-   Variables not defined in a site shell script can be set in the
-environment passed to `configure'.  However, some packages may run
-configure again during the build, and the customized values of these
-variables may be lost.  In order to avoid this problem, you should set
-them in the `configure' command line, using `VAR=value'.  For example:
+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.
 
-     ./configure CC=/usr/local2/bin/gcc
+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.
 
-causes the specified `gcc' to be used as the C compiler (unless it is
-overridden in the site shell script).
 
-Unfortunately, this technique does not work for `CONFIG_SHELL' due to
-an Autoconf bug.  Until the bug is fixed you can use this workaround:
+./configure options
+===================
 
-     CONFIG_SHELL=/bin/bash /bin/bash ./configure CONFIG_SHELL=/bin/bash
+--prefix=DIR            installs MPFR headers and library in DIR/include and
+                        DIR/lib respectively (the default is "/usr/local").
 
-`configure' Invocation
-======================
+--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
+                        and     --with-gmp-include=DIR/include
+                        (use either --with-gmp alone or one or both of
+                        --with-gmp-lib/--with-gmp-include)
+                        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.
 
-   `configure' recognizes the following options to control how it
-operates.
+--with-gmp-build=DIR    assumes that DIR contains the source of GMP and
+                        enables the use of GMP internals.
+                        Try to set CC/CFLAGS to GMP's ones. This is not
+                        guaranteed to work as the configure script does
+                        some compiler tests earlier, and the change may
+                        be too late.
+                        Warning! This option and the group of options
+                        --with-gmp are mutually exclusive.
 
-`--help'
-`-h'
-     Print a summary of all of the options to `configure', and exit.
+--enable-assert         build MPFR with assertions.
 
-`--help=short'
-`--help=recursive'
-     Print a summary of the options unique to this package's
-     `configure', and exit.  The `short' variant lists options used
-     only in the top level, while the `recursive' variant lists options
-     also present in any nested packages.
+--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
+                        storage class.
 
-`--version'
-`-V'
-     Print the version of Autoconf used to generate the `configure'
-     script, and exit.
+Run "./configure --help" to see the other options (autoconf default options).
 
-`--cache-file=FILE'
-     Enable the cache: use and save the results of the tests in FILE,
-     traditionally `config.cache'.  FILE defaults to `/dev/null' to
-     disable caching.
 
-`--config-cache'
-`-C'
-     Alias for `--cache-file=config.cache'.
-
-`--quiet'
-`--silent'
-`-q'
-     Do not print messages saying which checks are being made.  To
-     suppress all normal output, redirect it to `/dev/null' (any error
-     messages will still be shown).
+In case of problem
+==================
 
-`--srcdir=DIR'
-     Look for the package's source code in directory DIR.  Usually
-     `configure' can determine that directory automatically.
+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 <http://www.mpfr.org/faq.html>, which may be more
+    up-to-date);
+  * the MPFR web page for this version <http://www.mpfr.org/mpfr-3.0.0/>,
+    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"
+section below.
+
+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.
+
+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
+incorrect order).
+
+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: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=395177). See
+also http://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):
+    export C_INCLUDE_PATH="/usr/local/include:/other/path/include"
+    export LIBRARY_PATH="/usr/local/lib:/other/path/lib"
+    export LD_LIBRARY_PATH="$LIBRARY_PATH"
+
+  * With csh or tcsh:
+    setenv C_INCLUDE_PATH "/usr/local/include:/other/path/include"
+    setenv LIBRARY_PATH "/usr/local/lib:/other/path/lib"
+    setenv LD_LIBRARY_PATH "$LIBRARY_PATH"
+
+If you can't solve your problem, you should contact us at <mpfr@loria.fr>,
+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. Please send us
+also the log of the "configure" (config.log).
+
+Note that even if you can build MPFR with a C++ compiler, you can't run
+the test suite: C and C++ are not the same language! You should use a C
+compiler instead.
+
+
+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 5.3 (powerpc-ibm-aix5.3.0.0) with
+gcc 3.3.2 and GMP 4.2.1.
+
+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:
+
+  export OBJECT_MODE=64
+
+(in a sh-compatible shell). But you should also provide a correct CFLAGS
+value to the "configure" script: using --with-gmp-build is not sufficient
+due to the early compiler tests, as gcc will not compile any program if
+OBJECT_MODE is 64 and the -maix64 option is not provided.
+
+
+Notes on 32-bit Windows Applications (win32)
+============================================
+
+1 - We advise to use MinGW (http://www.mingw.org/), which is simpler and
+    less demanding than Cygwin. Contrary to Cygwin, it also provides native
+    Windows code. 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.
+
+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.
+    But if you want to generate a library for MinGW from a Cygwin
+    environment, you may need the -mno-cygwin gcc option (otherwise
+    a typical error is _P_WAIT being undeclared).
+
+3 - If you want to make libraries to work under another Windows compiler
+    like Visual C / C++, you have two options.  Since the unix-like *.a
+    library files are compatible with Windows *.lib files, you can simply
+    rename all *.a libraries to *.lib.  The second option is to build
+    MPFR with the Microsoft Visual Studio compiler to produce Windows
+    libraries directly (Visual Studio build projects for MPFR are
+    available at http://fp.gladman.plus.com/computing/gmp4win.htm).
+
+    With gmp-4.1.3, the only remaining problem seems to be the "alloca" calls
+    in GMP. Configuring GMP and MPFR with --enable-alloca=malloc-reentrant
+    should work (if you build MPFR with GMP internal files).
+
+    Or you could add the library
+     "$MINGWIN$/lib/gcc-lib/mingw32/$VERSION$/libgcc.a"
+    to your project: it contains all the extra-functions needed by a program
+    compiled by gcc (division of 64-bit integer, bcopy, alloca...).
+    Of course, include it if and only if your compiler is not gcc.
+
+4 - On Windows32 / MinGW, if all the tests fail, try to run the test suite
+    with "make check EXEEXT=".
+
+5 - 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'. For example, you can
+    compile and test MPFR with CC="gcc -D__USE_MINGW_ANSI_STDIO".
+
+    For example under Win32, the following problem has been experienced with
+    MPFR 2.4.0 RC1 and the MSVC runtime (msvcrt.dll):
+
+       Error in mpfr_vsprintf (s, "%.*Zi, %R*e, %Lf%n", ...);
+       expected: "00000010610209857723, -1.2345678875e+07, 0.032258"
+       got:      "00000010610209857723, -1.2345678875e+07, -0.000000"
+       FAIL: tsprintf.exe
+
+    This error is due to the MSVC runtime not supporting the L length modifier
+    for formatted output (e.g. printf with %Lf). You can check this with the
+    following program:
+
+       #include <stdio.h>
+       int main (void)
+       {
+         long double d = 1. / 31.;
+         printf ("%Lf\n", d);
+         return 0;
+       }
+
+    The expected output is 0.032258.
 
-`--prefix=DIR'
-     Use DIR as the installation prefix.  *note Installation Names::
-     for more details, including other options available for fine-tuning
-     the installation locations.
+    Note: The L modifier has been standard for a long time (it was added
+    in ISO C89).
 
-`--no-create'
-`-n'
-     Run the configure checks, but stop before creating any output
-     files.
+Notes on 64-bit Windows Applications (x64)
+==========================================
 
-`configure' also accepts some other, not widely useful, options.  Run
-`configure --help' for more details.
+[See the Notes on 32-bit Windows Applications, which might be relevant here,
+ in particular when running a 64-bit operating system]
 
+Cygwin and MinGW do not yet offer support for native Windows 64 builds but
+the 32-bit version of MPFR can be used to build 32-bit applications that
+will run on 64-bit Windows systems (see above). MPFR can be built as a native
+64-bit static or DLL library for Windows 64 using the Visual Studio build
+projects at http://fp.gladman.plus.com/computing/gmp4win.htm.