diff options
Diffstat (limited to 'libffi-3.0.4/README')
| -rw-r--r-- | libffi-3.0.4/README | 318 |
1 files changed, 318 insertions, 0 deletions
diff --git a/libffi-3.0.4/README b/libffi-3.0.4/README new file mode 100644 index 0000000..924a284 --- /dev/null +++ b/libffi-3.0.4/README @@ -0,0 +1,318 @@ +Status +====== + +libffi-3.0.4 was released on February 24, 2008. Check the libffi web +page for updates: <URL:http://sourceware.org/libffi/>. + + +What is libffi? +=============== + +Compilers for high level languages generate code that follow certain +conventions. These conventions are necessary, in part, for separate +compilation to work. One such convention is the "calling convention". +The "calling convention" is a set of assumptions made by the compiler +about where function arguments will be found on entry to a function. +A "calling convention" also specifies where the return value for a +function is found. + +Some programs may not know at the time of compilation what arguments +are to be passed to a function. For instance, an interpreter may be +told at run-time about the number and types of arguments used to call +a given function. Libffi can be used in such programs to provide a +bridge from the interpreter program to compiled code. + +The libffi library provides a portable, high level programming +interface to various calling conventions. This allows a programmer to +call any function specified by a call interface description at run +time. + +FFI stands for Foreign Function Interface. A foreign function +interface is the popular name for the interface that allows code +written in one language to call code written in another language. The +libffi library really only provides the lowest, machine dependent +layer of a fully featured foreign function interface. A layer must +exist above libffi that handles type conversions for values passed +between the two languages. + + +Supported Platforms +=================== + +Libffi has been ported to many different platforms, although this +release was only tested on: + + arm oabi linux + arm eabi linux + hppa linux + mips o32 linux (little endian) + powerpc darwin + powerpc64 linux + sparc solaris + sparc64 solaris + x86 cygwin + x86 darwin + x86 freebsd + x86 linux + x86 openbsd + x86-64 darwin + x86-64 linux + x86-64 OS X + x86-64 freebsd + +Please send additional platform test results to +libffi-discuss@sourceware.org. + +Installing libffi +================= + +[Note: before actually performing any of these installation steps, + you may wish to read the "Platform Specific Notes" below.] + +First you must configure the distribution for your particular +system. Go to the directory you wish to build libffi in and run the +"configure" program found in the root directory of the libffi source +distribution. + +You may want to tell configure where to install the libffi library and +header files. To do that, use the --prefix configure switch. Libffi +will install under /usr/local by default. + +If you want to enable extra run-time debugging checks use the the +--enable-debug configure switch. This is useful when your program dies +mysteriously while using libffi. + +Another useful configure switch is --enable-purify-safety. Using this +will add some extra code which will suppress certain warnings when you +are using Purify with libffi. Only use this switch when using +Purify, as it will slow down the library. + +Configure has many other options. Use "configure --help" to see them all. + +Once configure has finished, type "make". Note that you must be using +GNU make. You can ftp GNU make from prep.ai.mit.edu:/pub/gnu. + +To ensure that libffi is working as advertised, type "make check". +This will require that you have DejaGNU installed. + +To install the library and header files, type "make install". + + +Platform Specific Notes +======================= + + MIPS - Irix 5.3 & 6.x + --------------------- + +Irix 6.2 and better supports three different calling conventions: o32, +n32 and n64. Currently, libffi only supports both o32 and n32 under +Irix 6.x, but only o32 under Irix 5.3. Libffi will automatically be +configured for whichever calling convention it was built for. + +By default, the configure script will try to build libffi with the GNU +development tools. To build libffi with the SGI development tools, set +the environment variable CC to either "cc -32" or "cc -n32" before +running configure under Irix 6.x (depending on whether you want an o32 +or n32 library), or just "cc" for Irix 5.3. + +With the n32 calling convention, when returning structures smaller +than 16 bytes, be sure to provide an RVALUE that is 8 byte aligned. +Here's one way of forcing this: + + double struct_storage[2]; + my_small_struct *s = (my_small_struct *) struct_storage; + /* Use s for RVALUE */ + +If you don't do this you are liable to get spurious bus errors. + +"long long" values are not supported yet. + +You must use GNU Make to build libffi on SGI platforms. + + + PowerPC System V ABI + -------------------- + +There are two `System V ABI's which libffi implements for PowerPC. +They differ only in how small structures are returned from functions. + +In the FFI_SYSV version, structures that are 8 bytes or smaller are +returned in registers. This is what GCC does when it is configured +for solaris, and is what the System V ABI I have (dated September +1995) says. + +In the FFI_GCC_SYSV version, all structures are returned the same way: +by passing a pointer as the first argument to the function. This is +what GCC does when it is configured for linux or a generic sysv +target. + +EGCS 1.0.1 (and probably other versions of EGCS/GCC) also has a +inconsistency with the SysV ABI: When a procedure is called with many +floating-point arguments, some of them get put on the stack. They are +all supposed to be stored in double-precision format, even if they are +only single-precision, but EGCS stores single-precision arguments as +single-precision anyway. This causes one test to fail (the `many +arguments' test). + + +History +======= + +3.0.4 Feb-24-08 + Fix x86 OpenBSD configury. + +3.0.3 Feb-22-08 + Enable x86 OpenBSD thanks to Thomas Heller, and + x86-64 FreeBSD thanks to Björn König and Andreas Tobler. + Clean up test instruction in README. + +3.0.2 Feb-21-08 + Improved x86 FreeBSD support. + Thanks to Björn König. + +3.0.1 Feb-15-08 + Fix instruction cache flushing bug on MIPS. + Thanks to David Daney. + +3.0.0 Feb-15-08 + Many changes, mostly thanks to the GCC project. + Cygnus Solutions is now Red Hat. + + [10 years go by...] + +1.20 Oct-5-98 + Raffaele Sena produces ARM port. + +1.19 Oct-5-98 + Fixed x86 long double and long long return support. + m68k bug fixes from Andreas Schwab. + Patch for DU assembler compatibility for the Alpha from Richard + Henderson. + +1.18 Apr-17-98 + Bug fixes and MIPS configuration changes. + +1.17 Feb-24-98 + Bug fixes and m68k port from Andreas Schwab. PowerPC port from + Geoffrey Keating. Various bug x86, Sparc and MIPS bug fixes. + +1.16 Feb-11-98 + Richard Henderson produces Alpha port. + +1.15 Dec-4-97 + Fixed an n32 ABI bug. New libtool, auto* support. + +1.14 May-13-97 + libtool is now used to generate shared and static libraries. + Fixed a minor portability problem reported by Russ McManus + <mcmanr@eq.gs.com>. + +1.13 Dec-2-96 + Added --enable-purify-safety to keep Purify from complaining + about certain low level code. + Sparc fix for calling functions with < 6 args. + Linux x86 a.out fix. + +1.12 Nov-22-96 + Added missing ffi_type_void, needed for supporting void return + types. Fixed test case for non MIPS machines. Cygnus Support + is now Cygnus Solutions. + +1.11 Oct-30-96 + Added notes about GNU make. + +1.10 Oct-29-96 + Added configuration fix for non GNU compilers. + +1.09 Oct-29-96 + Added --enable-debug configure switch. Clean-ups based on LCLint + feedback. ffi_mips.h is always installed. Many configuration + fixes. Fixed ffitest.c for sparc builds. + +1.08 Oct-15-96 + Fixed n32 problem. Many clean-ups. + +1.07 Oct-14-96 + Gordon Irlam rewrites v8.S again. Bug fixes. + +1.06 Oct-14-96 + Gordon Irlam improved the sparc port. + +1.05 Oct-14-96 + Interface changes based on feedback. + +1.04 Oct-11-96 + Sparc port complete (modulo struct passing bug). + +1.03 Oct-10-96 + Passing struct args, and returning struct values works for + all architectures/calling conventions. Expanded tests. + +1.02 Oct-9-96 + Added SGI n32 support. Fixed bugs in both o32 and Linux support. + Added "make test". + +1.01 Oct-8-96 + Fixed float passing bug in mips version. Restructured some + of the code. Builds cleanly with SGI tools. + +1.00 Oct-7-96 + First release. No public announcement. + + +Authors & Credits +================= + +libffi was originally written by Anthony Green <green@redhat.com>. + +The developers of the GNU Compiler Collection project have made +innumerable valuable contributions. See the ChangeLog file for +details. + +Some of the ideas behind libffi were inspired by Gianni Mariani's free +gencall library for Silicon Graphics machines. + +The closure mechanism was designed and implemented by Kresten Krab +Thorup. + +Major processor architecture ports were contributed by the following +developers: + +alpha Richard Henderson +arm Raffaele Sena +cris Simon Posnjak, Hans-Peter Nilsson +frv Anthony Green +ia64 Hans Boehm +m32r Kazuhiro Inaoka +m68k Andreas Schwab +mips Anthony Green, Casey Marshall +mips64 David Daney +pa Randolph Chung, Dave Anglin, Andreas Tobler +powerpc Geoffrey Keating, Andreas Tobler, + David Edelsohn, John Hornkvist +powerpc64 Jakub Jelinek +s390 Gerhard Tonn, Ulrich Weigand +sh Kaz Kojima +sh64 Kaz Kojima +sparc Anthony Green, Gordon Irlam +x86 Anthony Green, Jon Beniston +x86-64 Bo Thorsen + +Jesper Skov and Andrew Haley both did more than their fair share of +stepping through the code and tracking down bugs. + +Thanks also to Tom Tromey for bug fixes, documentation and +configuration help. + +Thanks to Jim Blandy, who provided some useful feedback on the libffi +interface. + +Andreas Tobler has done a tremendous amount of work on the testsuite. + +Alex Oliva solved the executable page problem for SElinux. + +The list above is almost certainly incomplete and inaccurate. I'm +happy to make corrections or additions upon request. + +If you have a problem, or have found a bug, please send a note to +green@redhat.com. |