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diff --git a/gcc/README.g77 b/gcc/README.g77 deleted file mode 100644 index d0f5a4bc27b..00000000000 --- a/gcc/README.g77 +++ /dev/null @@ -1,263 +0,0 @@ -1998-08-11 - -This directory contains the egcs variant of version 0.5.24 of the -GNU Fortran compiler (g77). The GNU Fortran compiler is free software. -See the file COPYING.g77 for copying permission. - -Currently, two variants of g77 exist. One is the Free Software Foundation -(FSF) variant. The other is the egcs variant. As of egcs version 1.1, -these variants are kept fairly similar in most respects. Pertinent -differences, such as the layout of the source code, are specified below. - -Below, `[FSF]' denotes information applicable to only the FSF variant of -g77, while `[egcs]' denotes egcs-only information. - - -* IMPORTANT: Things you *must* do (or avoid) are marked with a * at the - beginning of the line in this file!!! - - -The email address to which bugs are to be reported is either -[FSF] <fortran@gnu.org> or [egcs] <egcs-bugs@egcs.cygnus.com>. - -* *DO NOT* send any email (reporting bugs, asking questions, etc.) to - either of these addresses without *first* reading the g77 documentation. - Use `info', Info mode in GNU Emacs, or a text viewer such as `more' to - do this. - - The g77 documentation is in the source files named `g77.info', - `g77.info-1', `g77.info-2', and so on in the `f' subdirectory. If these - files are not present or you can't find them, contact the person or - organization that put together the g77 distribution you are using (probably - not the FSF or egcs), or ask your system administrator for help. - - -This README applies to only the g77-specific portions of the source-code -tree that contains it. These portions include: - - - The README.g77 and [FSF] COPYING.g77 files, in this directory, "this - directory" being [FSF] the top-level directory containing a g77 - distribution or [egcs] the gcc/ subdirectory of an egcs distribution. - - - The g77 front end, in the f/ subdirectory of this directory. - - - The libg2c library, in [FSF] the f/runtime/ subdirectory of this - directory or [egcs] the libf2c/ directory under the top-level - directory of the egcs distribution. - - -* To build g77, you must have a source distribution of [FSF] gcc - version 2.8 or [egcs] egcs version 1.1. Do not attempt to use - any other version of gcc or egcs, because this version of g77 is - designed to work with only those versions. - - Note that you must have *source* copies of the gcc or egcs distribution! - You cannot build g77 just using binaries of gcc or egcs. Also, unless - you are an expert, avoid using any distribution of gcc or egcs not - identical to the ones distributed by the FSF and Cygnus Support, - respectively. The primary FSF distribution site is: - - <ftp://ftp.gnu.org/pub/gnu/> - - The primary egcs distribution site is: - - <ftp://ftp.cygnus.com/pub/egcs/> - - Both of these sites have approved mirror sites from which valid - distributions also may be obtained. - -* Do not attempt to combine the egcs version of g77 with the FSF - gcc distribution, or the FSF version of g77 with the egcs gcc - distribution. Although the differences are minor, they might - be sufficient to prevent g77 from building properly, or from - working properly if the build appears to succeed. - -[FSF] g77 is distributed as g77-<version>/f/ so that unpacking the g77 -distribution is done in the normal GNU way, resulting in a directory having -the version number in the name. However, to build g77, the g77 distribution -must be merged with an appropriate gcc distribution, normally in a gcc -source directory, before configuring, building, and installing g77. - -[FSF] If you have just unpacked the g77 distribution, before proceeding, -you must merge the contents of the g77 distribution with the appropriate -gcc distribution on your system. - -* [FSF] Read and follow the instructions in f/INSTALL that - explain how to merge a g77 source directory into a gcc source - directory. You can use Info to read the same installation - instructions via: - - info -f f/g77.info -n Unpacking - -[FSF] The resulting directory layout includes the following, where gcc/ -might be a link to, for example, gcc-2.8.1/: - - gcc/ Non-g77 files in gcc - gcc/COPYING.g77 A copy of the GPL, under which g77 is licensed - gcc/README.g77 This file - gcc/f/ GNU Fortran front end - gcc/f/runtime/ libg2c configuration and g2c.h file generation - gcc/f/runtime/libF77/ Non-I/O portion of libg2c - gcc/f/runtime/libI77/ I/O portion of libg2c - gcc/f/runtime/libU77/ Additional interfaces to libc for libg2c - -[FSF] Applying g77 patches in the form of .diff files is done by typing -`patch -p1 -d gcc' (where gcc/ contains the f/ subdirectory). That is, -g77 patches are distributed in the same form, and at the same directory -level, as patches to the gcc distribution. (Note: make sure you're -using GNU patch, version 2.5 or later! Other versions of patch -have trouble with g77-related patches.) - -[egcs] The egcs version of g77 is distributed already merged with -the rest of egcs (such as the gcc back end). - -[egcs] The resulting directory layout includes the following, where egcs/ -might be a link to, for example, egcs-1.1/: - - egcs/gcc/ Non-g77 files in gcc - egcs/gcc/README.g77 This file - egcs/gcc/f/ GNU Fortran front end - egcs/libf2c/ libg2c configuration and g2c.h file generation - egcs/libf2c/libF77/ Non-I/O portion of libg2c - egcs/libf2c/libI77/ I/O portion of libg2c - egcs/libf2c/libU77/ Additional interfaces to libc for libg2c - -[egcs] Applying g77-specific patches to egcs is done the same way as -applying other egcs patches. - - -Below, `libf2c/' shall denote [FSF] gcc/f/runtime/ or [egcs] egcs/libf2c/, -while `f/' shall denote [FSF] the rest of gcc/f/ or [egcs] egcs/gcc/f/. - - -Components of note in g77 are described below. - -f/ as a whole contains the program GNU Fortran (g77), while libf2c/ -contains a portion of the separate program f2c. Note: The libf2c -code is not part of the program g77, just distributed with it. - -f/ contains text files that document the Fortran compiler, source -files for the GNU Fortran Front End (FFE), and some other stuff. -The g77 compiler code is placed in f/ because it, along with its contents, -is designed to be a subdirectory of a GNU CC (gcc) source directory, gcc/, -which is structured so that language-specific front ends can be "dropped -in" as subdirectories. The C++ front end (g++), is an example of this -- -it resides in the cp/ subdirectory. Note that the C front end (also -referred to as gcc) is an exception to this, as its source files reside -in the gcc/ directory itself. - -libf2c/ contains the run-time libraries for the f2c program, also used -by g77. These libraries normally referred to collectively as libf2c. -When built as part of g77, libf2c is installed under the name libg2c to avoid -conflict with any existing version of libf2c, and thus is often referred -to as libg2c when the g77 version is specifically being referred to. - -The netlib version of libf2c/ contains two distinct libraries, libF77 and -libI77, each in their own subdirectories. In g77, this distinction is not -made, beyond maintaining the subdirectory structure in the source-code tree. - -libf2c/ is not part of the program g77, just distributed with it. It -contains files not present in the official (netlib) version of libf2c, -and also contains some minor changes made from libf2c, to fix some bugs, -and to facilitate automatic configuration, building, and installation of -libf2c (as libg2c) for use by g77 users. - -* See libf2c/README for more information, including licensing conditions - governing distribution of programs containing code from libg2c. - -libg2c, g77's version of libf2c, adds Dave Love's implementation of -libU77, in the libf2c/libU77/ directory. This library is distributed -under the GNU Library General Public License (LGPL) -- see the -file libf2c/libU77/COPYING.LIB for more information, as this license -governs distribution conditions for programs containing code from -this portion of the library. - - -Files of note in g77 are described below. - -f/BUGS lists some important bugs known to be in g77. Or: - - info -f f/g77.info -n "Actual Bugs" - -f/ChangeLog lists recent changes to g77 internals. - -libf2c/ChangeLog lists recent changes to libg2c internals. - -[FSF] f/INSTALL describes how to build and install GNU Fortran. Or: - - info -f f/g77.info -n Installation - -f/NEWS contains the per-release changes. These include the user-visible -changes described under "Changes" in the g77 documentation, plus internal -changes of import. Or: - - info -f f/g77.info -n News - -* All users of g77 (not just installers) should read f/g77.info* - as well, using the `more' command if neither the `info' command, - nor GNU Emacs (with its Info mode), are available, or if they - aren't yet accustomed to using these tools. Read f/BUGS and f/NEWS - plus, if you are planning on building or installing the FSF version - of g77, f/INSTALL, at the very least! All of these files are - readable as "plain text" files. - -* Also see <ftp://alpha.gnu.org/g77.plan> for up-to-date information - regarding g77 bug reports, known bugs, bug-fixes, and new versions. - - -The rest of this file is of note to only those who wish to -debug, modify, or test the FFE (in conjunction with the gcc back end). - -If you want to explore the FFE code, which lives entirely in f/, here -are a few clues. The file g77spec.c contains the g77-specific source code -for the `g77' command only -- this just forms a variant of the `gcc' -command, so, just as the `gcc' command itself does not contain -the C front end, the `g77' command does not contain the Fortran front -end (FFE). The FFE code ends up in an executable named `f771', which -does the actual compiling, so it contains the FFE plus the gcc back end -(the latter to do most of the optimization, and the code generation). - -The file parse.c is the source file for main() for a stand-alone FFE and -yyparse() for f771. (Stand-alone building of the FFE doesn't work these days.) -The file top.c contains the top-level FFE function ffe_file and it (along -with top.h) define all ffe_[a-z].*, ffe[A-Z].*, and FFE_[A-Za-z].* symbols. -The file fini.c is a main() program that is used when building the FFE to -generate C header and source files for recognizing keywords. The files -malloc.c and malloc.h comprise a memory manager that defines all -malloc_[a-z].*, malloc[A-Z].*, and MALLOC_[A-Za-z].* symbols. All other -modules named <xyz> are comprised of all files named <xyz>*.<ext> and -define all ffe<xyz>_[a-z].*, ffe<xyz>[A-Z].*, and FFE<XYZ>_[A-Za-z].* symbols. -If you understand all this, congratulations -- it's easier for me to remember -how it works than to type in these grep patterns (such as they are). But it -does make it easy to find where a symbol is defined -- for example, -the symbol "ffexyz_set_something" would be defined in xyz.h and implemented -there (if it's a macro) or in xyz.c. - -The "porting" files of note currently are: proj.h, which defines the -"language" used by all the other source files (the language being -Standard C plus some useful things like ARRAY_SIZE and such) -- change -this file when you find your system doesn't properly define a Standard C -macro or function, for example; target.h and target.c, which describe -the target machine in terms of what data types are supported, how they are -denoted (what C type does an INTEGER*8 map to, for example), how to convert -between them, and so on (though as of 0.5.3, more and more of this information -is being dynamically configured by ffecom_init_0); com.h and com.c, which -interface to the target back end (currently only FFE stand-alone and the GBE); -ste.c, which contains code for implementing recognized executable statements -in the target back end (again currently either FFE or GBE); src.h and src.c, -which describe information on the format(s) of source files (such as whether -they are never to be processed as case-insensitive with regard to Fortran -keywords); and proj.c, which contains whatever code is needed to support -the language defined by proj.h. - -If you want to debug the f771 executable, for example if it crashes, -note that the global variables "lineno" and "input_filename" are set -to reflect the current line being read by the lexer during the first-pass -analysis of a program unit and to reflect the current line being -processed during the second-pass compilation of a program unit. If -an invocation of the function ffestd_exec_end() is on the stack, -the compiler is in the second pass, otherwise it is in the first. -(This information might help you reduce a test case and/or work around -a bug in g77 until a fix is available.) - -Any questions or comments on these topics? Read the g77 documentation! |