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GNU Info File | 1994-07-15 | 21.5 KB | 470 lines |
- This is Info file gcc.info, produced by Makeinfo-1.54 from the input
- file gcc.texi.
-
- This file documents the use and the internals of the GNU compiler.
-
- Published by the Free Software Foundation 675 Massachusetts Avenue
- Cambridge, MA 02139 USA
-
- Copyright (C) 1988, 1989, 1992, 1993 Free Software Foundation, Inc.
-
- Permission is granted to make and distribute verbatim copies of this
- manual provided the copyright notice and this permission notice are
- preserved on all copies.
-
- Permission is granted to copy and distribute modified versions of
- this manual under the conditions for verbatim copying, provided also
- that the sections entitled "GNU General Public License" and "Protect
- Your Freedom--Fight `Look And Feel'" are included exactly as in the
- original, and provided that the entire resulting derived work is
- distributed under the terms of a permission notice identical to this
- one.
-
- Permission is granted to copy and distribute translations of this
- manual into another language, under the above conditions for modified
- versions, except that the sections entitled "GNU General Public
- License" and "Protect Your Freedom--Fight `Look And Feel'", and this
- permission notice, may be included in translations approved by the Free
- Software Foundation instead of in the original English.
-
- File: gcc.info, Node: Installation, Next: C Extensions, Prev: Invoking GCC, Up: Top
-
- Installing GNU CC
- *****************
-
- * Menu:
-
- * Configurations:: Configurations Supported by GNU CC.
- * Other Dir:: Compiling in a separate directory (not where the source is).
- * Cross-Compiler:: Building and installing a cross-compiler.
- * Sun Install:: See below for installation on the Sun.
- * VMS Install:: See below for installation on VMS.
- * Collect2:: How `collect2' works; how it finds `ld'.
- * Header Dirs:: Understanding the standard header file directories.
-
- Here is the procedure for installing GNU CC on a Unix system. See
- *Note VMS Install::, for VMS systems. In this section we assume you
- compile in the same directory that contains the source files; see *Note
- Other Dir::, to find out how to compile in a separate directory on Unix
- systems.
-
- You cannot install GNU C by itself on MSDOS; it will not compile
- under any MSDOS compiler except itself. You need to get the complete
- compilation package DJGPP, which includes binaries as well as sources,
- and includes all the necessary compilation tools and libraries.
-
- 1. If you have built GNU CC previously in the same directory for a
- different target machine, do `make distclean' to delete all files
- that might be invalid. One of the files this deletes is
- `Makefile'; if `make distclean' complains that `Makefile' does not
- exist, it probably means that the directory is already suitably
- clean.
-
- 2. On a System V release 4 system, make sure `/usr/bin' precedes
- `/usr/ucb' in `PATH'. The `cc' command in `/usr/ucb' uses
- libraries which have bugs.
-
- 3. Specify the host and target machine configurations. You do this by
- running the file `configure' with appropriate arguments.
-
- The `configure' script searches subdirectories of the source
- directory for other compilers that are to be integrated into GNU
- CC. The GNU compiler for C++, called G++ is in a subdirectory
- named `cp'. `configure' inserts rules into `Makefile' to build
- all of those compilers.
-
- If you are building a compiler to produce code for the machine it
- runs on, specify the "configuration name" with the `--target'
- option; the host will default to be the same as the target. (If
- you are building a cross-compiler, see *Note Cross-Compiler::.)
-
- Here is an example:
-
- ./configure --target=sparc-sun-sunos4.1
-
- If you run `configure' without specifying configuration arguments,
- `configure' tries to guess the type of host you are on, and uses
- that configuration type for both host and target. So you don't
- need to specify a configuration, for building a native compiler,
- unless `configure' cannot figure out what your configuration is.
-
- A configuration name may be canonical or it may be more or less
- abbreviated.
-
- A canonical configuration name has three parts, separated by
- dashes. It looks like this: `CPU-COMPANY-SYSTEM'. (The three
- parts may themselves contain dashes; `configure' can figure out
- which dashes serve which purpose.) For example,
- `m68k-sun-sunos4.1' specifies a Sun 3.
-
- You can also replace parts of the configuration by nicknames or
- aliases. For example, `sun3' stands for `m68k-sun', so
- `sun3-sunos4.1' is another way to specify a Sun 3. You can also
- use simply `sun3-sunos', since the version of SunOS is assumed by
- default to be version 4. `sun3-bsd' also works, since `configure'
- knows that the only BSD variant on a Sun 3 is SunOS.
-
- You can specify a version number after any of the system types,
- and some of the CPU types. In most cases, the version is
- irrelevant, and will be ignored. So you might as well specify the
- version if you know it.
-
- See *Note Configurations::, for a list of supported configuration
- names and notes on many of the configurations. You should check
- the notes in that section before proceding any further with the
- installation of GNU CC.
-
- There are four additional options you can specify independently to
- describe variant hardware and software configurations. These are
- `--with-gnu-as', `--with-gnu-ld', `--with-stabs' and `--nfp'.
-
- `--with-gnu-as'
- If you will use GNU CC with the GNU assembler (GAS), you
- should declare this by using the `--with-gnu-as' option when
- you run `configure'.
-
- Using this option does not install GAS. It only modifies the
- output of GNU CC to work with GAS. Building and installing
- GAS is up to you.
-
- Conversely, if you *do not* wish to use GAS and do not specify
- `--with-gnu-as' when building GNU CC, it is up to you to make
- sure that GAS is not installed. GNU CC searches for a
- program named `as' in various directories; if the program it
- finds is GAS, then it runs GAS. If you are not sure where
- GNU CC finds the assembler it is using, try specifying `-v'
- when you run it.
-
- The systems where it makes a difference whether you use GAS
- are
- `hppa1.0-ANY-ANY', `hppa1.1-ANY-ANY', `i386-ANY-sysv',
- `i386-ANY-isc',
- `i860-ANY-bsd', `m68k-bull-sysv', `m68k-hp-hpux',
- `m68k-sony-bsd',
- `m68k-altos-sysv', `m68000-hp-hpux', `m68000-att-sysv', and
- `mips-ANY'). On any other system, `--with-gnu-as' has no
- effect.
-
- On the systems listed above (except for the HP-PA and for ISC
- on the 386), if you use GAS, you should also use the GNU
- linker (and specify `--with-gnu-ld').
-
- `--with-gnu-ld'
- Specify the option `--with-gnu-ld' if you plan to use the GNU
- linker with GNU CC.
-
- This option does not cause the GNU linker to be installed; it
- just modifies the behavior of GNU CC to work with the GNU
- linker. Specifically, it inhibits the installation of
- `collect2', a program which otherwise serves as a front-end
- for the system's linker on most configurations.
-
- `--with-stabs'
- On MIPS based systems and on Alphas, you must specify whether
- you want GNU CC to create the normal ECOFF debugging format,
- or to use BSD-style stabs passed through the ECOFF symbol
- table. The normal ECOFF debug format cannot fully handle
- languages other than C. BSD stabs format can handle other
- languages, but it only works with the GNU debugger GDB.
-
- Normally, GNU CC uses the ECOFF debugging format by default;
- if you prefer BSD stabs, specify `--with-stabs' when you
- configure GNU CC.
-
- No matter which default you choose when you configure GNU CC,
- the user can use the `-gcoff' and `-gstabs+' options to
- specify explicitly the debug format for a particular
- compilation.
-
- `--with-stabs' is meaningful on the ISC system on the 386,
- also, if `--with-gas' is used. It selects use of stabs
- debugging information embedded in COFF output. This kind of
- debugging information supports C++ well; ordinary COFF
- debugging information does not.
-
- `--nfp'
- On certain systems, you must specify whether the machine has
- a floating point unit. These systems include
- `m68k-sun-sunosN' and `m68k-isi-bsd'. On any other system,
- `--nfp' currently has no effect, though perhaps there are
- other systems where it could usefully make a difference.
-
- Here we spell out what files will be set up by `configure'.
- Normally you need not be concerned with these files.
-
- * A symbolic link named `config.h' is made to the top-level
- config file for the machine you will run the compiler on
- (*note Config::.). This file is responsible for defining
- information about the host machine. It includes `tm.h'.
-
- The top-level config file is located in the subdirectory
- `config'. Its name is always `xm-SOMETHING.h'; usually
- `xm-MACHINE.h', but there are some exceptions.
-
- If your system does not support symbolic links, you might
- want to set up `config.h' to contain a `#include' command
- which refers to the appropriate file.
-
- * A symbolic link named `tconfig.h' is made to the top-level
- config file for your target machine. This is used for
- compiling certain programs to run on that machine.
-
- * A symbolic link named `tm.h' is made to the
- machine-description macro file for your target machine. It
- should be in the subdirectory `config' and its name is often
- `MACHINE.h'.
-
- * A symbolic link named `md' will be made to the machine
- description pattern file. It should be in the `config'
- subdirectory and its name should be `MACHINE.md'; but MACHINE
- is often not the same as the name used in the `tm.h' file
- because the `md' files are more general.
-
- * A symbolic link named `aux-output.c' will be made to the
- output subroutine file for your machine. It should be in the
- `config' subdirectory and its name should be `MACHINE.c'.
-
- * The command file `configure' also constructs the file
- `Makefile' by adding some text to the template file
- `Makefile.in'. The additional text comes from files in the
- `config' directory, named `t-TARGET' and `x-HOST'. If these
- files do not exist, it means nothing needs to be added for a
- given target or host.
-
- 4. The standard directory for installing GNU CC is `/usr/local/lib'.
- If you want to install its files somewhere else, specify
- `--prefix=DIR' when you run `configure'. Here DIR is a directory
- name to use instead of `/usr/local' for all purposes with one
- exception: the directory `/usr/local/include' is searched for
- header files no matter where you install the compiler. To override
- this name, use thge `--local-prefix' option below.
-
- 5. Specify `--local-prefix=DIR' if you want the compiler to search
- directory `DIR/include' for header files *instead* of
- `/usr/local/include'. (This is for systems that have different
- conventions for where to put site-specific things.)
-
- Unless you have a convention other than `/usr/local' for
- site-specific files, it is a bad idea to specify `--local-prefix'.
-
- 6. Make sure the Bison parser generator is installed. (This is
- unnecessary if the Bison output files `c-parse.c' and `cexp.c' are
- more recent than `c-parse.y' and `cexp.y' and you do not plan to
- change the `.y' files.)
-
- Bison versions older than Sept 8, 1988 will produce incorrect
- output for `c-parse.c'.
-
- 7. If you have chosen a configuration for GNU CC which requires other
- GNU tools (such as GAS or the GNU linker) instead of the standard
- system tools, install the required tools in the build directory
- under the names `as', `ld' or whatever is appropriate. This will
- enable the compiler to find the proper tools for compilation of
- the program `enquire'.
-
- Alternatively, you can do subsequent compilation using a value of
- the `PATH' environment variable such that the necessary GNU tools
- come before the standard system tools.
-
- 8. Build the compiler. Just type `make LANGUAGES=c' in the compiler
- directory.
-
- `LANGUAGES=c' specifies that only the C compiler should be
- compiled. The makefile normally builds compilers for all the
- supported languages; currently, C, C++ and Objective C. However,
- C is the only language that is sure to work when you build with
- other non-GNU C compilers. In addition, building anything but C
- at this stage is a waste of time.
-
- In general, you can specify the languages to build by typing the
- argument `LANGUAGES="LIST"', where LIST is one or more words from
- the list `c', `c++', and `objective-c'. If you have any
- additional GNU compilers as subdirectories of the GNU CC source
- directory, you may also specify their names in this list.
-
- Ignore any warnings you may see about "statement not reached" in
- `insn-emit.c'; they are normal. Also, warnings about "unknown
- escape sequence" are normal in `genopinit.c' and perhaps some
- other files. Likewise, you should ignore warnings about "constant
- is so large that it is unsigned" in `insn-emit.c' and
- `insn-recog.c'. Any other compilation errors may represent bugs in
- the port to your machine or operating system, and should be
- investigated and reported (*note Bugs::.).
-
- Some commercial compilers fail to compile GNU CC because they have
- bugs or limitations. For example, the Microsoft compiler is said
- to run out of macro space. Some Ultrix compilers run out of
- expression space; then you need to break up the statement where
- the problem happens.
-
- If you are building with a previous GNU C compiler, do not use
- `CC=gcc' on the make command or by editing the Makefile. Instead,
- use a full pathname to specify the compiler, such as
- `CC=/usr/local/bin/gcc'. This is because make might execute the
- `gcc' in the current directory before all of the compiler
- components have been built.
-
- 9. If you are building a cross-compiler, stop here. *Note
- Cross-Compiler::.
-
- 10. Move the first-stage object files and executables into a
- subdirectory with this command:
-
- make stage1
-
- The files are moved into a subdirectory named `stage1'. Once
- installation is complete, you may wish to delete these files with
- `rm -r stage1'.
-
- 11. If you have chosen a configuration for GNU CC which requires other
- GNU tools (such as GAS or the GNU linker) instead of the standard
- system tools, install the required tools in the `stage1'
- subdirectory under the names `as', `ld' or whatever is
- appropriate. This will enable the stage 1 compiler to find the
- proper tools in the following stage.
-
- Alternatively, you can do subsequent compilation using a value of
- the `PATH' environment variable such that the necessary GNU tools
- come before the standard system tools.
-
- 12. Recompile the compiler with itself, with this command:
-
- make CC="stage1/xgcc -Bstage1/" CFLAGS="-g -O"
-
- This is called making the stage 2 compiler.
-
- The command shown above builds compilers for all the supported
- languages. If you don't want them all, you can specify the
- languages to build by typing the argument `LANGUAGES="LIST"'. LIST
- should contain one or more words from the list `c', `c++',
- `objective-c', and `proto'. Separate the words with spaces.
- `proto' stands for the programs `protoize' and `unprotoize'; they
- are not a separate language, but you use `LANGUAGES' to enable or
- disable their installation.
-
- If you are going to build the stage 3 compiler, then you might
- want to build only the C language in stage 2.
-
- Once you have built the stage 2 compiler, if you are short of disk
- space, you can delete the subdirectory `stage1'.
-
- On a 68000 or 68020 system lacking floating point hardware, unless
- you have selected a `tm.h' file that expects by default that there
- is no such hardware, do this instead:
-
- make CC="stage1/xgcc -Bstage1/" CFLAGS="-g -O -msoft-float"
-
- 13. If you wish to test the compiler by compiling it with itself one
- more time, install any other necessary GNU tools (such as GAS or
- the GNU linker) in the `stage2' subdirectory as you did in the
- `stage1' subdirectory, then do this:
-
- make stage2
- make CC="stage2/xgcc -Bstage2/" CFLAGS="-g -O"
-
- This is called making the stage 3 compiler. Aside from the `-B'
- option, the compiler options should be the same as when you made
- the stage 2 compiler. But the `LANGUAGES' option need not be the
- same. The command shown above builds compilers for all the
- supported languages; if you don't want them all, you can specify
- the languages to build by typing the argument `LANGUAGES="LIST"',
- as described above.
-
- If you do not have to install any additional GNU tools, you may
- use the command
-
- make bootstrap LANGUAGES=LANGUAGE-LIST BOOT_CFLAGS=OPTION-LIST
-
- instead of making `stage1', `stage2', and performing the two
- compiler builds.
-
- 14. Then compare the latest object files with the stage 2 object
- files--they ought to be identical, aside from time stamps (if any).
-
- On some systems, meaningful comparison of object files is
- impossible; they always appear "different." This is currently
- true on Solaris and probably on all systems that use ELF object
- file format. On some versions of Irix on SGI machines and OSF/1
- on Alpha systems, you will not be able to compare the files
- without specifying `-save-temps'; see the description of
- individual systems above to see if you get comparison failures.
- You may have similar problems on other systems.
-
- Use this command to compare the files:
-
- make compare
-
- This will mention any object files that differ between stage 2 and
- stage 3. Any difference, no matter how innocuous, indicates that
- the stage 2 compiler has compiled GNU CC incorrectly, and is
- therefore a potentially serious bug which you should investigate
- and report (*note Bugs::.).
-
- If your system does not put time stamps in the object files, then
- this is a faster way to compare them (using the Bourne shell):
-
- for file in *.o; do
- cmp $file stage2/$file
- done
-
- If you have built the compiler with the `-mno-mips-tfile' option on
- MIPS machines, you will not be able to compare the files.
-
- 15. Build the Objective C library (if you have built the Objective C
- compiler). Here is the command to do this:
-
- make objc-runtime CC="stage2/xgcc -Bstage2/" CFLAGS="-g -O"
-
- 16. Install the compiler driver, the compiler's passes and run-time
- support with `make install'. Use the same value for `CC',
- `CFLAGS' and `LANGUAGES' that you used when compiling the files
- that are being installed. One reason this is necessary is that
- some versions of Make have bugs and recompile files gratuitously
- when you do this step. If you use the same variable values, those
- files will be recompiled properly.
-
- For example, if you have built the stage 2 compiler, you can use
- the following command:
-
- make install CC="stage2/xgcc -Bstage2/" CFLAGS="-g -O" LANGUAGES="LIST"
-
- This copies the files `cc1', `cpp' and `libgcc.a' to files `cc1',
- `cpp' and `libgcc.a' in the directory
- `/usr/local/lib/gcc-lib/TARGET/VERSION', which is where the
- compiler driver program looks for them. Here TARGET is the target
- machine type specified when you ran `configure', and VERSION is
- the version number of GNU CC. This naming scheme permits various
- versions and/or cross-compilers to coexist.
-
- This also copies the driver program `xgcc' into
- `/usr/local/bin/gcc', so that it appears in typical execution
- search paths.
-
- On some systems, this command causes recompilation of some files.
- This is usually due to bugs in `make'. You should either ignore
- this problem, or use GNU Make.
-
- *Warning: there is a bug in `alloca' in the Sun library. To avoid
- this bug, be sure to install the executables of GNU CC that were
- compiled by GNU CC. (That is, the executables from stage 2 or 3,
- not stage 1.) They use `alloca' as a built-in function and never
- the one in the library.*
-
- (It is usually better to install GNU CC executables from stage 2
- or 3, since they usually run faster than the ones compiled with
- some other compiler.)
-
- 17. Install the Objective C library (if you are installing the
- Objective C compiler). Here is the command to do this:
-
- make install-libobjc CC="stage2/xgcc -Bstage2/" CFLAGS="-g -O"
-
- 18. If you're going to use C++, it's likely that you need to also
- install the libg++ distribution. It should be available from the
- same place where you got the GNU C distribution. Just as GNU C
- does not distribute a C runtime library, it also does not include
- a C++ run-time library. All I/O functionality, special class
- libraries, etc., are available in the libg++ distribution.
-
-