`--prefix=PATHNAME' switch described above. TARGET is the target system triple, such as `sparc-sun-solaris2.7', and VERSION denotes the GCC version, such as 3.0. * If the target system is the same that you are building on, check operating system specific directories (e.g. `/usr/ccs/bin' on Sun Solaris 2). * Check in the `PATH' for a tool whose name is prefixed by the target system triple. * Check in the `PATH' for a tool whose name is not prefixed by the target system triple, if the host and target system triple are the same (in other words, we use a host tool if it can be used for the target as well). You may want to use `--with-as' if no assembler is installed in the directories listed above, or if you have multiple assemblers installed and want to choose one that is not found by the above rules. `--with-gnu-ld' Same as `--with-gnu-as' but for the linker. `--with-ld=PATHNAME' Same as `--with-as' but for the linker. `--with-stabs' Specify that stabs debugging information should be used instead of whatever format the host normally uses. Normally GCC uses the same debug format as the host system. On MIPS based systems and on Alphas, you must specify whether you want GCC 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, GCC uses the ECOFF debugging format by default; if you prefer BSD stabs, specify `--with-stabs' when you configure GCC. No matter which default you choose when you configure GCC, 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. `--with-stabs' is also meaningful on 386 systems running SVR4. It selects use of stabs debugging information embedded in ELF output. The C++ compiler currently (2.6.0) does not support the DWARF debugging information normally used on 386 SVR4 platforms; stabs provide a workable alternative. This requires gas and gdb, as the normal SVR4 tools can not generate or interpret stabs. `--disable-multilib' Specify that multiple target libraries to support different target variants, calling conventions, etc. should not be built. The default is to build a predefined set of them. Some targets provide finer-grained control over which multilibs are built (e.g., `--disable-softfloat'): `arc-*-elf*' biendian. `arm-*-*' fpu, 26bit, underscore, interwork, biendian, nofmult. `m68*-*-*' softfloat, m68881, m68000, m68020. `mips*-*-*' single-float, biendian, softfloat. `powerpc*-*-*, rs6000*-*-*' aix64, pthread, softfloat, powercpu, powerpccpu, powerpcos, biendian, sysv, aix. `--enable-threads' Specify that the target supports threads. This affects the Objective-C compiler and runtime library, and exception handling for other languages like C++ and Java. On some systems, this is the default. In general, the best (and, in many cases, the only known) threading model available will be configured for use. Beware that on some systems, GCC has not been taught what threading models are generally available for the system. In this case, `--enable-threads' is an alias for `--enable-threads=single'. `--disable-threads' Specify that threading support should be disabled for the system. This is an alias for `--enable-threads=single'. `--enable-threads=LIB' Specify that LIB is the thread support library. This affects the Objective-C compiler and runtime library, and exception handling for other languages like C++ and Java. The possibilities for LIB are: `aix' AIX thread support. `dce' DCE thread support. `gnat' Ada tasking support. For non-Ada programs, this setting is equivalent to `single'. When used in conjunction with the Ada run time, it causes GCC to use the same thread primitives as Ada uses. This option is necessary when using both Ada and the back end exception handling, which is the default for most Ada targets. `mach' Generic MACH thread support, known to work on NeXTSTEP. (Please note that the file needed to support this configuration, `gthr-mach.h', is missing and thus this setting will cause a known bootstrap failure.) `no' This is an alias for `single'. `posix' Generic POSIX/Unix98 thread support. `posix95' Generic POSIX/Unix95 thread support. `rtems' RTEMS thread support. `single' Disable thread support, should work for all platforms. `solaris' Sun Solaris 2 thread support. `vxworks' VxWorks thread support. `win32' Microsoft Win32 API thread support. `nks' Novell Kernel Services thread support. `--enable-tls' Specify that the target supports TLS (Thread Local Storage). Usually configure can correctly determine if TLS is supported. In cases where it guesses incorrectly, TLS can be explicitly enabled or disabled with `--enable-tls' or `--disable-tls'. This can happen if the assembler supports TLS but the C library does not, or if the assumptions made by the configure test are incorrect. `--disable-tls' Specify that the target does not support TLS. This is an alias for `--enable-tls=no'. `--with-cpu=CPU' Specify which cpu variant the compiler should generate code for by default. CPU will be used as the default value of the `-mcpu=' switch. This option is only supported on some targets, including ARM, i386, M68k, PowerPC, and SPARC. `--with-schedule=CPU' `--with-arch=CPU' `--with-tune=CPU' `--with-abi=ABI' `--with-fpu=TYPE' `--with-float=TYPE' These configure options provide default values for the `-mschedule=', `-march=', `-mtune=', `-mabi=', and `-mfpu=' options and for `-mhard-float' or `-msoft-float'. As with `--with-cpu', which switches will be accepted and acceptable values of the arguments depend on the target. `--with-mode=MODE' Specify if the compiler should default to `-marm' or `-mthumb'. This option is only supported on ARM targets. `--with-divide=TYPE' Specify how the compiler should generate code for checking for division by zero. This option is only supported on the MIPS target. The possibilities for TYPE are: `traps' Division by zero checks use conditional traps (this is the default on systems that support conditional traps). `breaks' Division by zero checks use the break instruction. `--with-llsc' On MIPS targets, make `-mllsc' the default when no `-mno-lsc' option is passed. This is the default for Linux-based targets, as the kernel will emulate them if the ISA does not provide them. `--without-llsc' On MIPS targets, make `-mno-llsc' the default when no `-mllsc' option is passed. `--enable-__cxa_atexit' Define if you want to use __cxa_atexit, rather than atexit, to register C++ destructors for local statics and global objects. This is essential for fully standards-compliant handling of destructors, but requires __cxa_atexit in libc. This option is currently only available on systems with GNU libc. When enabled, this will cause `-fuse-cxa-atexit' to be passed by default. `--enable-target-optspace' Specify that target libraries should be optimized for code space instead of code speed. This is the default for the m32r platform. `--disable-cpp' Specify that a user visible `cpp' program should not be installed. `--with-cpp-install-dir=DIRNAME' Specify that the user visible `cpp' program should be installed in `PREFIX/DIRNAME/cpp', in addition to BINDIR. `--enable-initfini-array' Force the use of sections `.init_array' and `.fini_array' (instead of `.init' and `.fini') for constructors and destructors. Option `--disable-initfini-array' has the opposite effect. If neither option is specified, the configure script will try to guess whether the `.init_array' and `.fini_array' sections are supported and, if they are, use them. `--enable-maintainer-mode' The build rules that regenerate the GCC master message catalog `gcc.pot' are normally disabled. This is because it can only be rebuilt if the complete source tree is present. If you have changed the sources and want to rebuild the catalog, configuring with `--enable-maintainer-mode' will enable this. Note that you need a recent version of the `gettext' tools to do so. `--disable-bootstrap' For a native build, the default configuration is to perform a 3-stage bootstrap of the compiler when `make' is invoked, testing that GCC can compile itself correctly. If you want to disable this process, you can configure with `--disable-bootstrap'. `--enable-bootstrap' In special cases, you may want to perform a 3-stage build even if the target and host triplets are different. This could happen when the host can run code compiled for the target (e.g. host is i686-linux, target is i486-linux). Starting from GCC 4.2, to do this you have to configure explicitly with `--enable-bootstrap'. `--enable-generated-files-in-srcdir' Neither the .c and .h files that are generated from Bison and flex nor the info manuals and man pages that are built from the .texi files are present in the SVN development tree. When building GCC from that development tree, or from one of our snapshots, those generated files are placed in your build directory, which allows for the source to be in a readonly directory. If you configure with `--enable-generated-files-in-srcdir' then those generated files will go into the source directory. This is mainly intended for generating release or prerelease tarballs of the GCC sources, since it is not a requirement that the users of source releases to have flex, Bison, or makeinfo. `--enable-version-specific-runtime-libs' Specify that runtime libraries should be installed in the compiler specific subdirectory (`LIBDIR/gcc') rather than the usual places. In addition, `libstdc++''s include files will be installed into `LIBDIR' unless you overruled it by using `--with-gxx-include-dir=DIRNAME'. Using this option is particularly useful if you intend to use several versions of GCC in parallel. This is currently supported by `libgfortran', `libjava', `libmudflap', `libstdc++', and `libobjc'. `--enable-languages=LANG1,LANG2,...' Specify that only a particular subset of compilers and their runtime libraries should be built. For a list of valid values for LANGN you can issue the following command in the `gcc' directory of your GCC source tree: grep language= */config-lang.in Currently, you can use any of the following: `all', `ada', `c', `c++', `fortran', `java', `objc', `obj-c++', `treelang'. Building the Ada compiler has special requirements, see below. If you do not pass this flag, or specify the option `all', then all default languages available in the `gcc' sub-tree will be configured. Ada, Objective-C++, and treelang are not default languages; the rest are. Re-defining `LANGUAGES' when calling `make' *does not* work anymore, as those language sub-directories might not have been configured! `--enable-stage1-languages=LANG1,LANG2,...' Specify that a particular subset of compilers and their runtime libraries should be built with the system C compiler during stage 1 of the bootstrap process, rather than only in later stages with the bootstrapped C compiler. The list of valid values is the same as for `--enable-languages', and the option `all' will select all of the languages enabled by `--enable-languages'. This option is primarily useful for GCC development; for instance, when a development version of the compiler cannot bootstrap due to compiler bugs, or when one is debugging front ends other than the C front end. When this option is used, one can then build the target libraries for the specified languages with the stage-1 compiler by using `make stage1-bubble all-target', or run the testsuite on the stage-1 compiler for the specified languages using `make stage1-start check-gcc'. `--disable-libada' Specify that the run-time libraries and tools used by GNAT should not be built. This can be useful for debugging, or for compatibility with previous Ada build procedures, when it was required to explicitly do a `make -C gcc gnatlib_and_tools'. `--disable-libssp' Specify that the run-time libraries for stack smashing protection should not be built. `--disable-libgomp' Specify that the run-time libraries used by GOMP should not be built. `--with-dwarf2' Specify that the compiler should use DWARF 2 debugging information as the default. `--enable-targets=all' `--enable-targets=TARGET_LIST' Some GCC targets, e.g. powerpc64-linux, build bi-arch compilers. These are compilers that are able to generate either 64-bit or 32-bit code. Typically, the corresponding 32-bit target, e.g. powerpc-linux for powerpc64-linux, only generates 32-bit code. This option enables the 32-bit target to be a bi-arch compiler, which is useful when you want a bi-arch compiler that defaults to 32-bit, and you are building a bi-arch or multi-arch binutils in a combined tree. Currently, this option only affects powerpc-linux and x86-linux. `--enable-secureplt' This option enables `-msecure-plt' by default for powerpc-linux. *Note RS/6000 and PowerPC Options: (gcc)RS/6000 and PowerPC Options, `--enable-cld' This option enables `-mcld' by default for 32-bit x86 targets. *Note i386 and x86-64 Options: (gcc)i386 and x86-64 Options, `--enable-win32-registry' `--enable-win32-registry=KEY' `--disable-win32-registry' The `--enable-win32-registry' option enables Microsoft Windows-hosted GCC to look up installations paths in the registry using the following key: `HKEY_LOCAL_MACHINE\SOFTWARE\Free Software Foundation\KEY' KEY defaults to GCC version number, and can be overridden by the `--enable-win32-registry=KEY' option. Vendors and distributors who use custom installers are encouraged to provide a different key, perhaps one comprised of vendor name and GCC version number, to avoid conflict with existing installations. This feature is enabled by default, and can be disabled by `--disable-win32-registry' option. This option has no effect on the other hosts. `--nfp' Specify that the machine does not have a floating point unit. This option only applies to `m68k-sun-sunosN'. On any other system, `--nfp' has no effect. `--enable-werror' `--disable-werror' `--enable-werror=yes' `--enable-werror=no' When you specify this option, it controls whether certain files in the compiler are built with `-Werror' in bootstrap stage2 and later. If you don't specify it, `-Werror' is turned on for the main development trunk. However it defaults to off for release branches and final releases. The specific files which get `-Werror' are controlled by the Makefiles. `--enable-checking' `--enable-checking=LIST' When you specify this option, the compiler is built to perform internal consistency checks of the requested complexity. This does not change the generated code, but adds error checking within the compiler. This will slow down the compiler and may only work properly if you are building the compiler with GCC. This is `yes' by default when building from SVN or snapshots, but `release' for releases. More control over the checks may be had by specifying LIST. The categories of checks available are `yes' (most common checks `assert,misc,tree,gc,rtlflag,runtime'), `no' (no checks at all), `all' (all but `valgrind'), `release' (cheapest checks `assert,runtime') or `none' (same as `no'). Individual checks can be enabled with these flags `assert', `df', `fold', `gc', `gcac' `misc', `rtl', `rtlflag', `runtime', `tree', and `valgrind'. The `valgrind' check requires the external `valgrind' simulator, available from `http://valgrind.org/'. The `df', `rtl', `gcac' and `valgrind' checks are very expensive. To disable all checking, `--disable-checking' or `--enable-checking=none' must be explicitly requested. Disabling assertions will make the compiler and runtime slightly faster but increase the risk of undetected internal errors causing wrong code to be generated. `--enable-coverage' `--enable-coverage=LEVEL' With this option, the compiler is built to collect self coverage information, every time it is run. This is for internal development purposes, and only works when the compiler is being built with gcc. The LEVEL argument controls whether the compiler is built optimized or not, values are `opt' and `noopt'. For coverage analysis you want to disable optimization, for performance analysis you want to enable optimization. When coverage is enabled, the default level is without optimization. `--enable-gather-detailed-mem-stats' When this option is specified more detailed information on memory allocation is gathered. This information is printed when using `-fmem-report'. `--with-gc' `--with-gc=CHOICE' With this option you can specify the garbage collector implementation used during the compilation process. CHOICE can be one of `page' and `zone', where `page' is the default. `--enable-nls' `--disable-nls' The `--enable-nls' option enables Native Language Support (NLS), which lets GCC output diagnostics in languages other than American English. Native Language Support is enabled by default if not doing a canadian cross build. The `--disable-nls' option disables NLS. `--with-included-gettext' If NLS is enabled, the `--with-included-gettext' option causes the build procedure to prefer its copy of GNU `gettext'. `--with-catgets' If NLS is enabled, and if the host lacks `gettext' but has the inferior `catgets' interface, the GCC build procedure normally ignores `catgets' and instead uses GCC's copy of the GNU `gettext' library. The `--with-catgets' option causes the build procedure to use the host's `catgets' in this situation. `--with-libiconv-prefix=DIR' Search for libiconv header files in `DIR/include' and libiconv library files in `DIR/lib'. `--enable-obsolete' Enable configuration for an obsoleted system. If you attempt to configure GCC for a system (build, host, or target) which has been obsoleted, and you do not specify this flag, configure will halt with an error message. All support for systems which have been obsoleted in one release of GCC is removed entirely in the next major release, unless someone steps forward to maintain the port. `--enable-decimal-float' `--enable-decimal-float=yes' `--enable-decimal-float=no' `--enable-decimal-float=bid' `--enable-decimal-float=dpd' `--disable-decimal-float' Enable (or disable) support for the C decimal floating point extension that is in the IEEE 754R extension to the IEEE754 floating point standard. This is enabled by default only on PowerPC, i386, and x86_64 GNU/Linux systems. Other systems may also support it, but require the user to specifically enable it. You can optionally control which decimal floating point format is used (either `bid' or `dpd'). The `bid' (binary integer decimal) format is default on i386 and x86_64 systems, and the `dpd' (densely packed decimal) format is default on PowerPC systems. `--enable-fixed-point' `--disable-fixed-point' Enable (or disable) support for C fixed-point arithmetic. This option is enabled by default for some targets (such as MIPS) which have hardware-support for fixed-point operations. On other targets, you may enable this option manually. `--with-long-double-128' Specify if `long double' type should be 128-bit by default on selected GNU/Linux architectures. If using `--without-long-double-128', `long double' will be by default 64-bit, the same as `double' type. When neither of these configure options are used, the default will be 128-bit `long double' when built against GNU C Library 2.4 and later, 64-bit `long double' otherwise. `--with-gmp=PATHNAME' `--with-gmp-include=PATHNAME' `--with-gmp-lib=PATHNAME' `--with-mpfr=PATHNAME' `--with-mpfr-include=PATHNAME' `--with-mpfr-lib=PATHNAME' If you do not have GMP (the GNU Multiple Precision library) and the MPFR Libraries installed in a standard location and you want to build GCC, you can explicitly specify the directory where they are installed (`--with-gmp=GMPINSTALLDIR', `--with-mpfr=MPFRINSTALLDIR'). The `--with-gmp=GMPINSTALLDIR' option is shorthand for `--with-gmp-lib=GMPINSTALLDIR/lib' and `--with-gmp-include=GMPINSTALLDIR/include'. Likewise the `--with-mpfr=MPFRINSTALLDIR' option is shorthand for `--with-mpfr-lib=MPFRINSTALLDIR/lib' and `--with-mpfr-include=MPFRINSTALLDIR/include'. If these shorthand assumptions are not correct, you can use the explicit include and lib options directly. `--with-debug-prefix-map=MAP' Convert source directory names using `-fdebug-prefix-map' when building runtime libraries. `MAP' is a space-separated list of maps of the form `OLD=NEW'. Cross-Compiler-Specific Options ------------------------------- The following options only apply to building cross compilers. `--with-sysroot' `--with-sysroot=DIR' Tells GCC to consider DIR as the root of a tree that contains a (subset of) the root filesystem of the target operating system. Target system headers, libraries and run-time object files will be searched in there. The specified directory is not copied into the install tree, unlike the options `--with-headers' and `--with-libs' that this option obsoletes. The default value, in case `--with-sysroot' is not given an argument, is `${gcc_tooldir}/sys-root'. If the specified directory is a subdirectory of `${exec_prefix}', then it will be found relative to the GCC binaries if the installation tree is moved. `--with-build-sysroot' `--with-build-sysroot=DIR' Tells GCC to consider DIR as the system root (see `--with-sysroot') while building target libraries, instead of the directory specified with `--with-sysroot'. This option is only useful when you are already using `--with-sysroot'. You can use `--with-build-sysroot' when you are configuring with `--prefix' set to a directory that is different from the one in which you are installing GCC and your target libraries. This option affects the system root for the compiler used to build target libraries (which runs on the build system); it does not affect the compiler which is used to build GCC itself. `--with-headers' `--with-headers=DIR' Deprecated in favor of `--with-sysroot'. Specifies that target headers are available when building a cross compiler. The DIR argument specifies a directory which has the target include files. These include files will be copied into the `gcc' install directory. _This option with the DIR argument is required_ when building a cross compiler, if `PREFIX/TARGET/sys-include' doesn't pre-exist. If `PREFIX/TARGET/sys-include' does pre-exist, the DIR argument may be omitted. `fixincludes' will be run on these files to make them compatible with GCC. `--without-headers' Tells GCC not use any target headers from a libc when building a cross compiler. When crossing to GNU/Linux, you need the headers so GCC can build the exception handling for libgcc. `--with-libs' `--with-libs=``DIR1 DIR2 ... DIRN''' Deprecated in favor of `--with-sysroot'. Specifies a list of directories which contain the target runtime libraries. These libraries will be copied into the `gcc' install directory. If the directory list is omitted, this option has no effect. `--with-newlib' Specifies that `newlib' is being used as the target C library. This causes `__eprintf' to be omitted from `libgcc.a' on the assumption that it will be provided by `newlib'. `--with-build-time-tools=DIR' Specifies where to find the set of target tools (assembler, linker, etc.) that will be used while building GCC itself. This option can be useful if the directory layouts are different between the system you are building GCC on, and the system where you will deploy it. For example, on a `ia64-hp-hpux' system, you may have the GNU assembler and linker in `/usr/bin', and the native tools in a different path, and build a toolchain that expects to find the native tools in `/usr/bin'. When you use this option, you should ensure that DIR includes `ar', `as', `ld', `nm', `ranlib' and `strip' if necessary, and possibly `objdump'. Otherwise, GCC may use an inconsistent set of tools. Java-Specific Options --------------------- The following option applies to the build of the Java front end. `--disable-libgcj' Specify that the run-time libraries used by GCJ should not be built. This is useful in case you intend to use GCJ with some other run-time, or you're going to install it separately, or it just happens not to build on your particular machine. In general, if the Java front end is enabled, the GCJ libraries will be enabled too, unless they're known to not work on the target platform. If GCJ is enabled but `libgcj' isn't built, you may need to port it; in this case, before modifying the top-level `configure.in' so that `libgcj' is enabled by default on this platform, you may use `--enable-libgcj' to override the default. The following options apply to building `libgcj'. General Options ............... `--enable-java-maintainer-mode' By default the `libjava' build will not attempt to compile the `.java' source files to `.class'. Instead, it will use the `.class' files from the source tree. If you use this option you must have executables named `ecj1' and `gjavah' in your path for use by the build. You must use this option if you intend to modify any `.java' files in `libjava'. `--with-java-home=DIRNAME' This `libjava' option overrides the default value of the `java.home' system property. It is also used to set `sun.boot.class.path' to `DIRNAME/lib/rt.jar'. By default `java.home' is set to `PREFIX' and `sun.boot.class.path' to `DATADIR/java/libgcj-VERSION.jar'. `--with-ecj-jar=FILENAME' This option can be used to specify the location of an external jar file containing the Eclipse Java compiler. A specially modified version of this compiler is used by `gcj' to parse `.java' source files. If this option is given, the `libjava' build will create and install an `ecj1' executable which uses this jar file at runtime. If this option is not given, but an `ecj.jar' file is found in the topmost source tree at configure time, then the `libgcj' build will create and install `ecj1', and will also install the discovered `ecj.jar' into a suitable place in the install tree. If `ecj1' is not installed, then the user will have to supply one on his path in order for `gcj' to properly parse `.java' source files. A suitable jar is available from `ftp://sourceware.org/pub/java/'. `--disable-getenv-properties' Don't set system properties from `GCJ_PROPERTIES'. `--enable-hash-synchronization' Use a global hash table for monitor locks. Ordinarily, `libgcj''s `configure' script automatically makes the correct choice for this option for your platform. Only use this if you know you need the library to be configured differently. `--enable-interpreter' Enable the Java interpreter. The interpreter is automatically enabled by default on all platforms that support it. This option is really only useful if you want to disable the interpreter (using `--disable-interpreter'). `--disable-java-net' Disable java.net. This disables the native part of java.net only, using non-functional stubs for native method implementations. `--disable-jvmpi' Disable JVMPI support. `--disable-libgcj-bc' Disable BC ABI compilation of certain parts of libgcj. By default, some portions of libgcj are compiled with `-findirect-dispatch' and `-fno-indirect-classes', allowing them to be overridden at run-time. If `--disable-libgcj-bc' is specified, libgcj is built without these options. This allows the compile-time linker to resolve dependencies when statically linking to libgcj. However it makes it impossible to override the affected portions of libgcj at run-time. `--with-ecos' Enable runtime eCos target support. `--without-libffi' Don't use `libffi'. This will disable the interpreter and JNI support as well, as these require `libffi' to work. `--enable-libgcj-debug' Enable runtime debugging code. `--enable-libgcj-multifile' If specified, causes all `.java' source files to be compiled into `.class' files in one invocation of `gcj'. This can speed up build time, but is more resource-intensive. If this option is unspecified or disabled, `gcj' is invoked once for each `.java' file to compile into a `.class' file. `--with-libiconv-prefix=DIR' Search for libiconv in `DIR/include' and `DIR/lib'. `--enable-sjlj-exceptions' Force use of the `setjmp'/`longjmp'-based scheme for exceptions. `configure' ordinarily picks the correct value based on the platform. Only use this option if you are sure you need a different setting. `--with-system-zlib' Use installed `zlib' rather than that included with GCC. `--with-win32-nlsapi=ansi, unicows or unicode' Indicates how MinGW `libgcj' translates between UNICODE characters and the Win32 API. `ansi' Use the single-byte `char' and the Win32 A functions natively, translating to and from UNICODE when using these functions. If unspecified, this is the default. `unicows' Use the `WCHAR' and Win32 W functions natively. Adds `-lunicows' to `libgcj.spec' to link with `libunicows'. `unicows.dll' needs to be deployed on Microsoft Windows 9X machines running built executables. `libunicows.a', an open-source import library around Microsoft's `unicows.dll', is obtained from `http://libunicows.sourceforge.net/', which also gives details on getting `unicows.dll' from Microsoft. `unicode' Use the `WCHAR' and Win32 W functions natively. Does _not_ add `-lunicows' to `libgcj.spec'. The built executables will only run on Microsoft Windows NT and above. AWT-Specific Options .................... `--with-x' Use the X Window System. `--enable-java-awt=PEER(S)' Specifies the AWT peer library or libraries to build alongside `libgcj'. If this option is unspecified or disabled, AWT will be non-functional. Current valid values are `gtk' and `xlib'. Multiple libraries should be separated by a comma (i.e. `--enable-java-awt=gtk,xlib'). `--enable-gtk-cairo' Build the cairo Graphics2D implementation on GTK. `--enable-java-gc=TYPE' Choose garbage collector. Defaults to `boehm' if unspecified. `--disable-gtktest' Do not try to compile and run a test GTK+ program. `--disable-glibtest' Do not try to compile and run a test GLIB program. `--with-libart-prefix=PFX' Prefix where libart is installed (optional). `--with-libart-exec-prefix=PFX' Exec prefix where libart is installed (optional). `--disable-libarttest' Do not try to compile and run a test libart program.  File: gccinstall.info, Node: Building, Next: Testing, Prev: Configuration, Up: Installing GCC 5 Building ********** Now that GCC is configured, you are ready to build the compiler and runtime libraries. Some commands executed when making the compiler may fail (return a nonzero status) and be ignored by `make'. These failures, which are often due to files that were not found, are expected, and can safely be ignored. It is normal to have compiler warnings when compiling certain files. Unless you are a GCC developer, you can generally ignore these warnings unless they cause compilation to fail. Developers should attempt to fix any warnings encountered, however they can temporarily continue past warnings-as-errors by specifying the configure flag `--disable-werror'. On certain old systems, defining certain environment variables such as `CC' can interfere with the functioning of `make'. If you encounter seemingly strange errors when trying to build the compiler in a directory other than the source directory, it could be because you have previously configured the compiler in the source directory. Make sure you have done all the necessary preparations. If you build GCC on a BSD system using a directory stored in an old System V file system, problems may occur in running `fixincludes' if the System V file system doesn't support symbolic links. These problems result in a failure to fix the declaration of `size_t' in `sys/types.h'. If you find that `size_t' is a signed type and that type mismatches occur, this could be the cause. The solution is not to use such a directory for building GCC. When building from SVN or snapshots and enabling the `treelang' front end, or if you modify `*.y' files, you need the Bison parser generator installed. If you do not modify `*.y' files, releases contain the Bison-generated files and you do not need Bison installed to build them. Note that most front ends now use hand-written parsers, which can be modified with no need for Bison. Similarly, when building from SVN or snapshots, or if you modify `*.l' files, you need the Flex lexical analyzer generator installed. There is still one Flex-based lexical analyzer (part of the build machinery, not of GCC itself) that is used even if you only build the C front end. When building from SVN or snapshots, or if you modify Texinfo documentation, you need version 4.4 or later of Texinfo installed if you want Info documentation to be regenerated. Releases contain Info documentation pre-built for the unmodified documentation in the release. 5.1 Building a native compiler ============================== For a native build, the default configuration is to perform a 3-stage bootstrap of the compiler when `make' is invoked. This will build the entire GCC system and ensure that it compiles itself correctly. It can be disabled with the `--disable-bootstrap' parameter to `configure', but bootstrapping is suggested because the compiler will be tested more completely and could also have better performance. The bootstrapping process will complete the following steps: * Build tools necessary to build the compiler. * Perform a 3-stage bootstrap of the compiler. This includes building three times the target tools for use by the compiler such as binutils (bfd, binutils, gas, gprof, ld, and opcodes) if they have been individually linked or moved into the top level GCC source tree before configuring. * Perform a comparison test of the stage2 and stage3 compilers. * Build runtime libraries using the stage3 compiler from the previous step. If you are short on disk space you might consider `make bootstrap-lean' instead. The sequence of compilation is the same described above, but object files from the stage1 and stage2 of the 3-stage bootstrap of the compiler are deleted as soon as they are no longer needed. If you want to save additional space during the bootstrap and in the final installation as well, you can build the compiler binaries without debugging information as in the following example. This will save roughly 40% of disk space both for the bootstrap and the final installation. (Libraries will still contain debugging information.) make CFLAGS='-O' LIBCFLAGS='-g -O2' \ LIBCXXFLAGS='-g -O2 -fno-implicit-templates' bootstrap If you wish to use non-default GCC flags when compiling the stage2 and stage3 compilers, set `BOOT_CFLAGS' on the command line when doing `make'. Non-default optimization flags are less well tested here than the default of `-g -O2', but should still work. In a few cases, you may find that you need to specify special flags such as `-msoft-float' here to complete the bootstrap; or, if the native compiler miscompiles the stage1 compiler, you may need to work around this, by choosing `BOOT_CFLAGS' to avoid the parts of the stage1 compiler that were miscompiled, or by using `make bootstrap4' to increase the number of stages of bootstrap. Note that using non-standard `CFLAGS' can cause bootstrap to fail if these trigger a warning with the new compiler. For example using `-O2 -g -mcpu=i686' on `i686-pc-linux-gnu' will cause bootstrap failure as `-mcpu=' is deprecated in 3.4.0 and above. If you used the flag `--enable-languages=...' to restrict the compilers to be built, only those you've actually enabled will be built. This will of course only build those runtime libraries, for which the particular compiler has been built. Please note, that re-defining `LANGUAGES' when calling `make' *does not* work anymore! If the comparison of stage2 and stage3 fails, this normally indicates that the stage2 compiler has compiled GCC incorrectly, and is therefore a potentially serious bug which you should investigate and report. (On a few systems, meaningful comparison of object files is impossible; they always appear "different". If you encounter this problem, you will need to disable comparison in the `Makefile'.) If you do not want to bootstrap your compiler, you can configure with `--disable-bootstrap'. In particular cases, you may want to bootstrap your compiler even if the target system is not the same as the one you are building on: for example, you could build a `powerpc-unknown-linux-gnu' toolchain on a `powerpc64-unknown-linux-gnu' host. In this case, pass `--enable-bootstrap' to the configure script. 5.2 Building a cross compiler ============================= When building a cross compiler, it is not generally possible to do a 3-stage bootstrap of the compiler. This makes for an interesting problem as parts of GCC can only be built with GCC. To build a cross compiler, we first recommend building and installing a native compiler. You can then use the native GCC compiler to build the cross compiler. The installed native compiler needs to be GCC version 2.95 or later. If the cross compiler is to be built with support for the Java programming language and the ability to compile .java source files is desired, the installed native compiler used to build the cross compiler needs to be the same GCC version as the cross compiler. In addition the cross compiler needs to be configured with `--with-ecj-jar=...'. Assuming you have already installed a native copy of GCC and configured your cross compiler, issue the command `make', which performs the following steps: * Build host tools necessary to build the compiler. * Build target tools for use by the compiler such as binutils (bfd, binutils, gas, gprof, ld, and opcodes) if they have been individually linked or moved into the top level GCC source tree before configuring. * Build the compiler (single stage only). * Build runtime libraries using the compiler from the previous step. Note that if an error occurs in any step the make process will exit. If you are not building GNU binutils in the same source tree as GCC, you will need a cross-assembler and cross-linker installed before configuring GCC. Put them in the directory `PREFIX/TARGET/bin'. Here is a table of the tools you should put in this directory: `as' This should be the cross-assembler. `ld' This should be the cross-linker. `ar' This should be the cross-archiver: a program which can manipulate archive files (linker libraries) in the target machine's format. `ranlib' This should be a program to construct a symbol table in an archive file. The installation of GCC will find these programs in that directory, and copy or link them to the proper place to for the cross-compiler to find them when run later. The easiest way to provide these files is to build the Binutils package. Configure it with the same `--host' and `--target' options that you use for configuring GCC, then build and install them. They install their executables automatically into the proper directory. Alas, they do not support all the targets that GCC supports. If you are not building a C library in the same source tree as GCC, you should also provide the target libraries and headers before configuring GCC, specifying the directories with `--with-sysroot' or `--with-headers' and `--with-libs'. Many targets also require "start files" such as `crt0.o' and `crtn.o' which are linked into each executable. There may be several alternatives for `crt0.o', for use with profiling or other compilation options. Check your target's definition of `STARTFILE_SPEC' to find out what start files it uses. 5.3 Building in parallel ======================== GNU Make 3.79 and above, which is necessary to build GCC, support building in parallel. To activate this, you can use `make -j 2' instead of `make'. You can also specify a bigger number, and in most cases using a value greater than the number of processors in your machine will result in fewer and shorter I/O latency hits, thus improving overall throughput; this is especially true for slow drives and network filesystems. 5.4 Building the Ada compiler ============================= In order to build GNAT, the Ada compiler, you need a working GNAT compiler (GNAT version 3.14 or later, or GCC version 3.1 or later). This includes GNAT tools such as `gnatmake' and `gnatlink', since the Ada front end is written in Ada and uses some GNAT-specific extensions. In order to build a cross compiler, it is suggested to install the new compiler as native first, and then use it to build the cross compiler. `configure' does not test whether the GNAT installation works and has a sufficiently recent version; if too old a GNAT version is installed, the build will fail unless `--enable-languages' is used to disable building the Ada front end. `ADA_INCLUDE_PATH' and `ADA_OBJECT_PATH' environment variables must not be set when building the Ada compiler, the Ada tools, or the Ada runtime libraries. You can check that your build environment is clean by verifying that `gnatls -v' lists only one explicit path in each section. 5.5 Building with profile feedback ================================== It is possible to use profile feedback to optimize the compiler itself. This should result in a faster compiler binary. Experiments done on x86 using gcc 3.3 showed approximately 7 percent speedup on compiling C programs. To bootstrap the compiler with profile feedback, use `make profiledbootstrap'. When `make profiledbootstrap' is run, it will first build a `stage1' compiler. This compiler is used to build a `stageprofile' compiler instrumented to collect execution counts of instruction and branch probabilities. Then runtime libraries are compiled with profile collected. Finally a `stagefeedback' compiler is built using the information collected. Unlike standard bootstrap, several additional restrictions apply. The compiler used to build `stage1' needs to support a 64-bit integral type. It is recommended to only use GCC for this. Also parallel make is currently not supported since collisions in profile collecting may occur.  File: gccinstall.info, Node: Testing, Next: Final install, Prev: Building, Up: Installing GCC 6 Installing GCC: Testing ************************* Before you install GCC, we encourage you to run the testsuites and to compare your results with results from a similar configuration that have been submitted to the gcc-testresults mailing list. Some of these archived results are linked from the build status lists at `http://gcc.gnu.org/buildstat.html', although not everyone who reports a successful build runs the testsuites and submits the results. This step is optional and may require you to download additional software, but it can give you confidence in your new GCC installation or point out problems before you install and start using your new GCC. First, you must have downloaded the testsuites. These are part of the full distribution, but if you downloaded the "core" compiler plus any front ends, you must download the testsuites separately. Second, you must have the testing tools installed. This includes DejaGnu, Tcl, and Expect; the DejaGnu site has links to these. If the directories where `runtest' and `expect' were installed are not in the `PATH', you may need to set the following environment variables appropriately, as in the following example (which assumes that DejaGnu has been installed under `/usr/local'): TCL_LIBRARY = /usr/local/share/tcl8.0 DEJAGNULIBS = /usr/local/share/dejagnu (On systems such as Cygwin, these paths are required to be actual paths, not mounts or links; presumably this is due to some lack of portability in the DejaGnu code.) Finally, you can run the testsuite (which may take a long time): cd OBJDIR; make -k check This will test various components of GCC, such as compiler front ends and runtime libraries. While running the testsuite, DejaGnu might emit some harmless messages resembling `WARNING: Couldn't find the global config file.' or `WARNING: Couldn't find tool init file' that can be ignored. If you are testing a cross-compiler, you may want to run the testsuite on a simulator as described at `http://gcc.gnu.org/simtest-howto.html'. 6.1 How can you run the testsuite on selected tests? ==================================================== In order to run sets of tests selectively, there are targets `make check-gcc' and `make check-g++' in the `gcc' subdirectory of the object directory. You can also just run `make check' in a subdirectory of the object directory. A more selective way to just run all `gcc' execute tests in the testsuite is to use make check-gcc RUNTESTFLAGS="execute.exp OTHER-OPTIONS" Likewise, in order to run only the `g++' "old-deja" tests in the testsuite with filenames matching `9805*', you would use make check-g++ RUNTESTFLAGS="old-deja.exp=9805* OTHER-OPTIONS" The `*.exp' files are located in the testsuite directories of the GCC source, the most important ones being `compile.exp', `execute.exp', `dg.exp' and `old-deja.exp'. To get a list of the possible `*.exp' files, pipe the output of `make check' into a file and look at the `Running ... .exp' lines. 6.2 Passing options and running multiple testsuites =================================================== You can pass multiple options to the testsuite using the `--target_board' option of DejaGNU, either passed as part of `RUNTESTFLAGS', or directly to `runtest' if you prefer to work outside the makefiles. For example, make check-g++ RUNTESTFLAGS="--target_board=unix/-O3/-fmerge-constants" will run the standard `g++' testsuites ("unix" is the target name for a standard native testsuite situation), passing `-O3 -fmerge-constants' to the compiler on every test, i.e., slashes separate options. You can run the testsuites multiple times using combinations of options with a syntax similar to the brace expansion of popular shells: ..."--target_board=arm-sim\{-mhard-float,-msoft-float\}\{-O1,-O2,-O3,\}" (Note the empty option caused by the trailing comma in the final group.) The following will run each testsuite eight times using the `arm-sim' target, as if you had specified all possible combinations yourself: --target_board=arm-sim/-mhard-float/-O1 --target_board=arm-sim/-mhard-float/-O2 --target_board=arm-sim/-mhard-float/-O3 --target_board=arm-sim/-mhard-float --target_board=arm-sim/-msoft-float/-O1 --target_board=arm-sim/-msoft-float/-O2 --target_board=arm-sim/-msoft-float/-O3 --target_board=arm-sim/-msoft-float They can be combined as many times as you wish, in arbitrary ways. This list: ..."--target_board=unix/-Wextra\{-O3,-fno-strength\}\{-fomit-frame,\}" will generate four combinations, all involving `-Wextra'. The disadvantage to this method is that the testsuites are run in serial, which is a waste on multiprocessor systems. For users with GNU Make and a shell which performs brace expansion, you can run the testsuites in parallel by having the shell perform the combinations and `make' do the parallel runs. Instead of using `--target_board', use a special makefile target: make -jN check-TESTSUITE//TEST-TARGET/OPTION1/OPTION2/... For example, make -j3 check-gcc//sh-hms-sim/{-m1,-m2,-m3,-m3e,-m4}/{,-nofpu} will run three concurrent "make-gcc" testsuites, eventually testing all ten combinations as described above. Note that this is currently only supported in the `gcc' subdirectory. (To see how this works, try typing `echo' before the example given here.) 6.3 Additional testing for Java Class Libraries =============================================== The Java runtime tests can be executed via `make check' in the `TARGET/libjava/testsuite' directory in the build tree. The Mauve Project provides a suite of tests for the Java Class Libraries. This suite can be run as part of libgcj testing by placing the Mauve tree within the libjava testsuite at `libjava/testsuite/libjava.mauve/mauve', or by specifying the location of that tree when invoking `make', as in `make MAUVEDIR=~/mauve check'. 6.4 How to interpret test results ================================= The result of running the testsuite are various `*.sum' and `*.log' files in the testsuite subdirectories. The `*.log' files contain a detailed log of the compiler invocations and the corresponding results, the `*.sum' files summarize the results. These summaries contain status codes for all tests: * PASS: the test passed as expected * XPASS: the test unexpectedly passed * FAIL: the test unexpectedly failed * XFAIL: the test failed as expected * UNSUPPORTED: the test is not supported on this platform * ERROR: the testsuite detected an error * WARNING: the testsuite detected a possible problem It is normal for some tests to report unexpected failures. At the current time the testing harness does not allow fine grained control over whether or not a test is expected to fail. This problem should be fixed in future releases. 6.5 Submitting test results =========================== If you want to report the results to the GCC project, use the `contrib/test_summary' shell script. Start it in the OBJDIR with SRCDIR/contrib/test_summary -p your_commentary.txt \ -m gcc-testresults@gcc.gnu.org |sh This script uses the `Mail' program to send the results, so make sure it is in your `PATH'. The file `your_commentary.txt' is prepended to the testsuite summary and should contain any special remarks you have on your results or your build environment. Please do not edit the testsuite result block or the subject line, as these messages may be automatically processed.  File: gccinstall.info, Node: Final install, Prev: Testing, Up: Installing GCC 7 Installing GCC: Final installation ************************************ Now that GCC has been built (and optionally tested), you can install it with cd OBJDIR; make install We strongly recommend to install into a target directory where there is no previous version of GCC present. Also, the GNAT runtime should not be stripped, as this would break certain features of the debugger that depend on this debugging information (catching Ada exceptions for instance). That step completes the installation of GCC; user level binaries can be found in `PREFIX/bin' where PREFIX is the value you specified with the `--prefix' to configure (or `/usr/local' by default). (If you specified `--bindir', that directory will be used instead; otherwise, if you specified `--exec-prefix', `EXEC-PREFIX/bin' will be used.) Headers for the C++ and Java libraries are installed in `PREFIX/include'; libraries in `LIBDIR' (normally `PREFIX/lib'); internal parts of the compiler in `LIBDIR/gcc' and `LIBEXECDIR/gcc'; documentation in info format in `INFODIR' (normally `PREFIX/info'). When installing cross-compilers, GCC's executables are not only installed into `BINDIR', that is, `EXEC-PREFIX/bin', but additionally into `EXEC-PREFIX/TARGET-ALIAS/bin', if that directory exists. Typically, such "tooldirs" hold target-specific binutils, including assembler and linker. Installation into a temporary staging area or into a `chroot' jail can be achieved with the command make DESTDIR=PATH-TO-ROOTDIR install where PATH-TO-ROOTDIR is the absolute path of a directory relative to which all installation paths will be interpreted. Note that the directory specified by `DESTDIR' need not exist yet; it will be created if necessary. There is a subtle point with tooldirs and `DESTDIR': If you relocate a cross-compiler installation with e.g. `DESTDIR=ROOTDIR', then the directory `ROOTDIR/EXEC-PREFIX/TARGET-ALIAS/bin' will be filled with duplicated GCC executables only if it already exists, it will not be created otherwise. This is regarded as a feature, not as a bug, because it gives slightly more control to the packagers using the `DESTDIR' feature. If you are bootstrapping a released version of GCC then please quickly review the build status page for your release, available from `http://gcc.gnu.org/buildstat.html'. If your system is not listed for the version of GCC that you built, send a note to indicating that you successfully built and installed GCC. Include the following information: * Output from running `SRCDIR/config.guess'. Do not send that file itself, just the one-line output from running it. * The output of `gcc -v' for your newly installed `gcc'. This tells us which version of GCC you built and the options you passed to configure. * Whether you enabled all languages or a subset of them. If you used a full distribution then this information is part of the configure options in the output of `gcc -v', but if you downloaded the "core" compiler plus additional front ends then it isn't apparent which ones you built unless you tell us about it. * If the build was for GNU/Linux, also include: * The distribution name and version (e.g., Red Hat 7.1 or Debian 2.2.3); this information should be available from `/etc/issue'. * The version of the Linux kernel, available from `uname --version' or `uname -a'. * The version of glibc you used; for RPM-based systems like Red Hat, Mandrake, and SuSE type `rpm -q glibc' to get the glibc version, and on systems like Debian and Progeny use `dpkg -l libc6'. For other systems, you can include similar information if you think it is relevant. * Any other information that you think would be useful to people building GCC on the same configuration. The new entry in the build status list will include a link to the archived copy of your message. We'd also like to know if the *note host/target specific installation notes: Specific. didn't include your host/target information or if that information is incomplete or out of date. Send a note to detailing how the information should be changed. If you find a bug, please report it following the bug reporting guidelines. If you want to print the GCC manuals, do `cd OBJDIR; make dvi'. You will need to have `texi2dvi' (version at least 4.4) and TeX installed. This creates a number of `.dvi' files in subdirectories of `OBJDIR'; these may be converted for printing with programs such as `dvips'. Alternately, by using `make pdf' in place of `make dvi', you can create documentation in the form of `.pdf' files; this requires `texi2pdf', which is included with Texinfo version 4.8 and later. You can also buy printed manuals from the Free Software Foundation, though such manuals may not be for the most recent version of GCC. If you would like to generate online HTML documentation, do `cd OBJDIR; make html' and HTML will be generated for the gcc manuals in `OBJDIR/gcc/HTML'.  File: gccinstall.info, Node: Binaries, Next: Specific, Prev: Installing GCC, Up: Top 8 Installing GCC: Binaries ************************** We are often asked about pre-compiled versions of GCC. While we cannot provide these for all platforms, below you'll find links to binaries for various platforms where creating them by yourself is not easy due to various reasons. Please note that we did not create these binaries, nor do we support them. If you have any problems installing them, please contact their makers. * AIX: * Bull's Freeware and Shareware Archive for AIX; * UCLA Software Library for AIX. * DOS--DJGPP. * Renesas H8/300[HS]--GNU Development Tools for the Renesas H8/300[HS] Series. * HP-UX: * HP-UX Porting Center; * Binaries for HP-UX 11.00 at Aachen University of Technology. * Motorola 68HC11/68HC12--GNU Development Tools for the Motorola 68HC11/68HC12. * SCO OpenServer/Unixware. * Solaris 2 (SPARC, Intel)--Sunfreeware. * SGI--SGI Freeware. * Microsoft Windows: * The Cygwin project; * The MinGW project. * The Written Word offers binaries for AIX 4.3.2. IRIX 6.5, Digital UNIX 4.0D and 5.1, GNU/Linux (i386), HP-UX 10.20, 11.00, and 11.11, and Solaris/SPARC 2.5.1, 2.6, 7, 8, and 9. * OpenPKG offers binaries for quite a number of platforms. * The GFortran Wiki has links to GNU Fortran binaries for several platforms. In addition to those specific offerings, you can get a binary distribution CD-ROM from the Free Software Foundation. It contains binaries for a number of platforms, and includes not only GCC, but other stuff as well. The current CD does not contain the latest version of GCC, but it should allow bootstrapping the compiler. An updated version of that disk is in the works.  File: gccinstall.info, Node: Specific, Next: Old, Prev: Binaries, Up: Top 9 Host/target specific installation notes for GCC ************************************************* Please read this document carefully _before_ installing the GNU Compiler Collection on your machine. Note that this list of install notes is _not_ a list of supported hosts or targets. Not all supported hosts and targets are listed here, only the ones that require host-specific or target-specific information are. alpha*-*-* ========== This section contains general configuration information for all alpha-based platforms using ELF (in particular, ignore this section for DEC OSF/1, Digital UNIX and Tru64 UNIX). In addition to reading this section, please read all other sections that match your target. We require binutils 2.11.2 or newer. Previous binutils releases had a number of problems with DWARF 2 debugging information, not the least of which is incorrect linking of shared libraries. alpha*-dec-osf* =============== Systems using processors that implement the DEC Alpha architecture and are running the DEC/Compaq Unix (DEC OSF/1, Digital UNIX, or Compaq Tru64 UNIX) operating system, for example the DEC Alpha AXP systems. As of GCC 3.2, versions before `alpha*-dec-osf4' are no longer supported. (These are the versions which identify themselves as DEC OSF/1.) In Digital Unix V4.0, virtual memory exhausted bootstrap failures may be fixed by configuring with `--with-gc=simple', reconfiguring Kernel Virtual Memory and Swap parameters per the `/usr/sbin/sys_check' Tuning Suggestions, or applying the patch in `http://gcc.gnu.org/ml/gcc/2002-08/msg00822.html'. In Tru64 UNIX V5.1, Compaq introduced a new assembler that does not currently (2001-06-13) work with `mips-tfile'. As a workaround, we need to use the old assembler, invoked via the barely documented `-oldas' option. To bootstrap GCC, you either need to use the Compaq C Compiler: % CC=cc SRCDIR/configure [OPTIONS] [TARGET] or you can use a copy of GCC 2.95.3 or higher built on Tru64 UNIX V4.0: % CC=gcc -Wa,-oldas SRCDIR/configure [OPTIONS] [TARGET] As of GNU binutils 2.11.2, neither GNU `as' nor GNU `ld' are supported on Tru64 UNIX, so you must not configure GCC with `--with-gnu-as' or `--with-gnu-ld'. GCC writes a `.verstamp' directive to the assembler output file unless it is built as a cross-compiler. It gets the version to use from the system header file `/usr/include/stamp.h'. If you install a new version of DEC Unix, you should rebuild GCC to pick up the new version stamp. `make compare' may fail on old versions of DEC Unix unless you add `-save-temps' to `CFLAGS'. On these systems, the name of the assembler input file is stored in the object file, and that makes comparison fail if it differs between the `stage1' and `stage2' compilations. The option `-save-temps' forces a fixed name to be used for the assembler input file, instead of a randomly chosen name in `/tmp'. Do not add `-save-temps' unless the comparisons fail without that option. If you add `-save-temps', you will have to manually delete the `.i' and `.s' files after each series of compilations. GCC now supports both the native (ECOFF) debugging format used by DBX and GDB and an encapsulated STABS format for use only with GDB. See the discussion of the `--with-stabs' option of `configure' above for more information on these formats and how to select them. There is a bug in DEC's assembler that produces incorrect line numbers for ECOFF format when the `.align' directive is used. To work around this problem, GCC will not emit such alignment directives while writing ECOFF format debugging information even if optimization is being performed. Unfortunately, this has the very undesirable side-effect that code addresses when `-O' is specified are different depending on whether or not `-g' is also specified. To avoid this behavior, specify `-gstabs+' and use GDB instead of DBX. DEC is now aware of this problem with the assembler and hopes to provide a fix shortly. alphaev5-cray-unicosmk* ======================= Cray T3E systems running Unicos/Mk. This port is incomplete and has many known bugs. We hope to improve the support for this target soon. Currently, only the C front end is supported, and it is not possible to build parallel applications. Cray modules are not supported; in particular, Craylibs are assumed to be in `/opt/ctl/craylibs/craylibs'. On this platform, you need to tell GCC where to find the assembler and the linker. The simplest way to do so is by providing `--with-as' and `--with-ld' to `configure', e.g. configure --with-as=/opt/ctl/bin/cam --with-ld=/opt/ctl/bin/cld \ --enable-languages=c The comparison test at the end of the bootstrapping process fails on Unicos/Mk because the assembler inserts timestamps into object files. You should be able to work around this by doing `make all' after getting this failure. arc-*-elf ========= Argonaut ARC processor. This configuration is intended for embedded systems. arm-*-elf ======