1.4: update version to 1.4.0+svn.
-------- diffstat follows --------
/branches/1.4/.version | 2 1 1 0 +-
1 file changed, 1 insertion(+), 1 deletion(-)
1 File.........: overview.txt
2 Content......: Overview of how crosstool-NG works.
3 Copyrigth....: (C) 2007 Yann E. MORIN <yann.morin.1998@anciens.enib.fr>
4 License......: Creative Commons Attribution Share Alike (CC-by-sa), v2.5
14 Installing crosstool-NG
17 Preparing for packaging
20 Configuring crosstool-NG
21 Interesting config options
22 Re-building an existing toolchain
24 Stopping and restarting a build
25 Testing all toolchains at once
26 Overriding the number of // jobs
33 Adding a new version of a component
41 crosstool-NG aims at building toolchains. Toolchains are an essential component
42 in a software development project. It will compile, assemble and link the code
43 that is being developed. Some pieces of the toolchain will eventually end up
44 in the resulting binary/ies: static libraries are but an example.
46 So, a toolchain is a very sensitive piece of software, as any bug in one of the
47 components, or a poorly configured component, can lead to execution problems,
48 ranging from poor performance, to applications ending unexpectedly, to
49 mis-behaving software (which more than often is hard to detect), to hardware
50 damage, or even to human risks (which is more than regrettable).
52 Toolchains are made of different piece of software, each being quite complex
53 and requiring specially crafted options to build and work seamlessly. This
54 is usually not that easy, even in the not-so-trivial case of native toolchains.
55 The work reaches a higher degree of complexity when it comes to cross-
56 compilation, where it can become quite a nightmare...
58 Some cross-toolchains exist on the internet, and can be used for general
59 development, but they have a number of limitations:
60 - they can be general purpose, in that they are configured for the majority:
61 no optimisation for your specific target,
62 - they can be prepared for a specific target and thus are not easy to use,
63 nor optimised for, or even supporting your target,
64 - they often are using aging components (compiler, C library, etc...) not
65 supporting special features of your shiny new processor;
66 On the other side, these toolchain offer some advantages:
67 - they are ready to use and quite easy to install and setup,
68 - they are proven if used by a wide community.
70 But once you want to get all the juice out of your specific hardware, you will
71 want to build your own toolchain. This is where crosstool-NG comes into play.
73 There are also a number of tools that build toolchains for specific needs,
74 which are not really scalable. Examples are:
75 - buildroot (buildroot.uclibc.org) whose main purpose is to build root file
76 systems, hence the name. But once you have your toolchain with buildroot,
77 part of it is installed in the root-to-be, so if you want to build a whole
78 new root, you either have to save the existing one as a template and
79 restore it later, or restart again from scratch. This is not convenient,
80 - ptxdist (www.pengutronix.de/software/ptxdist), whose purpose is very
82 - other projects (openembedded.org for example), which are again used to
83 build root file systems.
85 crosstool-NG is really targeted at building toolchains, and only toolchains.
86 It is then up to you to use it the way you want.
93 crosstool was first 'conceived' by Dan Kegel, who offered it to the community
94 as a set of scripts, a repository of patches, and some pre-configured, general
95 purpose setup files to be used to configure crosstool. This is available at
96 http://www.kegel.com/crosstool, and the subversion repository is hosted on
97 google at http://code.google.com/p/crosstool/.
99 I once managed to add support for uClibc-based toolchains, but it did not make
100 into mainline, mostly because I didn't have time to port the patch forward to
101 the new versions, due in part to the big effort it was taking.
103 So I decided to clean up crosstool in the state it was, re-order the things
104 in place, add appropriate support for what I needed, that is uClibc support
105 and a menu-driven configuration, named the new implementation crosstool-NG,
106 (standing for crosstool Next Generation, as many other comunity projects do,
107 and as a wink at the TV series "Star Trek: The Next Generation" ;-) ) and
108 made it available to the community, in case it was of interest to any one.
110 ___________________________
112 Installing crosstool-NG /
113 ________________________/
115 There are two ways you can use crosstool-NG:
116 - build and install it, then get rid of the sources like you'd do for most
118 - or only build it and run from the source directory.
120 The former should be used if you got crosstool-NG from a packaged tarball, see
121 "Install method", below, while the latter is most useful for developpers that
122 checked the code out from SVN, and want to submit patches, see "The Hacker's
128 If you go for the install, then you just follow the classical, but yet easy
130 ./configure --prefix=/some/place
133 export PATH="${PATH}:/some/place/bin"
135 You can then get rid of crosstool-NG source. Next create a directory to serve
136 as a working place, cd in there and run:
139 See below for complete usage.
144 If you go the hacker's way, then the usage is a bit different, although very
149 Now, *do not* remove crosstool-NG sources. They are needed to run crosstool-NG!
150 Stay in the directory holding the sources, and run:
153 See below for complete usage.
155 Now, provided you checked-out the code, you can send me your interesting changes
159 and mailing me the result! :-P
161 Preparing for packaging |
162 ------------------------+
164 If you plan on packaging crosstool-NG, you surely don't want to install it
165 in your root file system. The install procedure of crosstool-NG honors the
168 ./configure --prefix=/usr
170 make DESTDIR=/packaging/place install
175 crosstool-NG comes with a shell script fragment that defines bash-compatible
176 completion. That shell fragment is currently not installed automatically, but
179 To install the shell script fragment, you have two options:
180 - install system-wide, most probably by copying ct-ng.comp into
181 /etc/bash_completion.d/
182 - install for a single user, by copying ct-ng.comp into ${HOME}/ and
183 sourcing this file from your ${HOME}/.bashrc
188 Some people contibuted code that couldn't get merged for various reasons. This
189 code is available as patches in the contrib/ sub-directory. These patches are
190 to be applied to the source of crosstool-NG, prior to installing.
192 An easy way to use contributed code is to pass the --with-contrib= option to
193 ./configure. The possible values depend upon which contributions are packaged
194 with your version, but you can get with it with passing one of those two
197 will list all available contributions
200 will select all avalaible contributions
202 There is no guarantee that a particuliar contribution applies to the current
203 version of crosstool-ng, or that it will work at all. Use contributions at
206 ____________________________
208 Configuring crosstool-NG /
209 _________________________/
211 crosstool-NG is configured with a configurator presenting a menu-stuctured set
212 of options. These options let you specify the way you want your toolchain
213 built, where you want it installed, what architecture and specific processor it
214 will support, the version of the components you want to use, etc... The
215 value for those options are then stored in a configuration file.
217 The configurator works the same way you configure your Linux kernel. It is
218 assumed you now how to handle this.
220 To enter the menu, type:
223 Almost every config item has a help entry. Read them carefully.
225 String and number options can refer to environment variables. In such a case,
226 you must use the shell syntax: ${VAR}. You shall neither single- nor double-
227 quote the string/number options.
229 There are three environment variables that are computed by crosstool-NG, and
233 It represents the target tuple you are building for. You can use it for
234 example in the installation/prefix directory, such as:
235 /opt/x-tools/${CT_TARGET}
238 The top directory where crosstool-NG is running. You shouldn't need it in
239 most cases. There is one case where you may need it: if you have local
240 patches and you store them in your running directory, you can refer to them
241 by using CT_TOP_DIR, such as:
242 ${CT_TOP_DIR}/patches.myproject
245 The version of crosstool-NG you are using. Not much use for you, but it's
246 there if you need it.
248 Interesting config options |
249 ---------------------------+
251 CT_LOCAL_TARBALLS_DIR:
252 If you already have some tarballs in a direcotry, enter it here. That will
253 speed up the retrieving phase, where crosstool-NG would otherwise download
257 This is where the toolchain will be installed in (and for now, where it
258 will run from). Common use is to add the target tuple in the directory
259 path, such as (see above):
260 /opt/x-tools/${CT_TARGET}
263 An identifier for your toolchain, will take place in the vendor part of the
264 target tuple. It shall *not* contain spaces or dashes. Usually, keep it
265 to a one-word string, or use underscores to separate words if you need.
266 Avoid dots, commas, and special characters.
269 An alias for the toolchian. It will be used as a prefix to the toolchain
270 tools. For example, you will have ${CT_TARGET_ALIAS}-gcc
272 Also, if you think you don't see enough versions, you can try to enable one of
276 Show obsolete versions or tools. Most of the time, you don't want to base
277 your toolchain on too old a version (of gcc, for example). But at times, it
278 can come handy to use such an old version for regression tests. Those old
279 versions are hidden behind CT_OBSOLETE. Those versions (or features) are so
280 marked because maintaining support for those in crosstool-NG would be too
281 costly, time-wise, and time is dear.
284 Show experimental versions or tools. Again, you might not want to base your
285 toolchain on too recent tools (eg. gcc) for production. But if you need a
286 feature present only in a recent version, or a new tool, you can find them
287 hidden behind CT_EXPERIMENTAL. Those versions (or features) did not (yet)
288 receive thorough testing in crosstool-NG, and/or are not mature enough to
291 Re-building an existing toolchain |
292 ----------------------------------+
294 If you have an existing toolchain, you can re-use the options used to build it
295 to create a new toolchain. That needs a very little bit of effort on your side
296 but is quite easy. The options to build a toolchain are saved with the
297 toolchain, and you can retrieve this configuration by running:
300 This will dump the configuration to stdout, so to rebuild a toolchain with this
301 configuration, the following is all you need to do:
302 ${CT_TARGET}-config >.config
305 Then, you can review and change the configuration by running:
308 ________________________
310 Running crosstool-NG /
311 _____________________/
313 To build the toolchain, simply type:
316 This will use the above configuration to retrieve, extract and patch the
317 components, build, install and eventually test your newly built toolchain.
319 You are then free to add the toolchain /bin directory in your PATH to use
322 In any case, you can get some terse help. Just type:
327 Stopping and restarting a build |
328 --------------------------------+
330 If you want to stop the build after a step you are debugging, you can pass the
331 variable STOP to make:
334 Conversely, if you want to restart a build at a specific step you are
335 debugging, you can pass the RESTART variable to make:
336 ct-ng RESTART=some_step
338 Alternatively, you can call make with the name of a step to just do that step:
341 ct-ng RESTART=libc_headers STOP=libc_headers
343 The shortcuts +step_name and step_name+ allow to respectively stop or restart
345 ct-ng +libc_headers and: ct-ng libc_headers+
347 ct-ng STOP=libc_headers and: ct-ng RESTART=libc_headers
349 To obtain the list of acceptable steps, please call:
352 Note that in order to restart a build, you'll have to say 'Y' to the config
353 option CT_DEBUG_CT_SAVE_STEPS, and that the previous build effectively went
356 Building all toolchains at once |
357 --------------------------------+
359 You can build all samples; simply call:
362 Overriding the number of // jobs |
363 ---------------------------------+
365 If you want to override the number of jobs to run in // (the -j option to
366 make), you can either re-enter the menuconfig, or simply add it on the command
370 which tells crosstool-NG to override the number of // jobs to 4.
372 You can see the actions that support overriding the number of // jobs in
373 the help menu. Those are the ones with [.#] after them (eg. build[.#] or
374 build-all[.#], and so on...).
379 The crosstool-NG script 'ct-ng' is a Makefile-script. It does *not* execute
380 in parallel (there is not much to gain). When speaking of // jobs, we are
381 refering to the number of // jobs when making the *components*. That is, we
382 speak of the number of // jobs used to build gcc, glibc, and so on...
385 _______________________
387 Using the toolchain /
388 ____________________/
390 Using the toolchain is as simple as adding the toolchain's bin directory in
392 export PATH="${PATH}:/your/toolchain/path/bin"
394 and then using the target tuple to tell the build systems to use your
396 ./configure --target=your-target-tuple
398 make CC=your-target-tuple-gcc
400 make CROSS_COMPILE=your-target-tuple-
403 It is strongly advised not to use the toolchain sys-root directory as an
404 install directory for your programs/packages. If you do so, you will not be
405 able to use your toolchain for another project. It is even strongly advised
406 that your toolchain is chmod-ed to read-only once successfully build, so that
407 you don't go polluting your toolchain with your programs/packages' files.
409 Thus, when you build a program/package, install it in a separate directory,
410 eg. /your/root. This directory is the /image/ of what would be in the root file
411 system of your target, and will contain all that your programs/packages have
414 When your root directory is ready, it is still missing some important bits: the
415 toolchain's libraries. To populate your root directory with those libs, just
417 your-target-tuple-populate -s /your/root -d /your/root-populated
419 This will copy /your/root into /your/root-populated, and put the needed and only
420 the needed libraries there. Thus you don't polute /your/root with any cruft that
421 would no longer be needed should you have to remove stuff. /your/root always
422 contains only those things you install in it.
424 You can then use /your/root-populated to build up your file system image, a
425 tarball, or to NFS-mount it from your target, or whatever you need.
427 populate accepts the following options:
430 Use 'src_dir' as the 'source', un-populated root directory
433 Put the 'destination', populated root directory in 'dst_dir'
436 Remove 'dst_dir' if it previously existed
439 Be verbose, and tell what's going on (you can see exactly where libs are
450 There are four kinds of toolchains you could encounter.
452 First off, you must understand the following: when it comes to compilers there
453 are up to four machines involved:
454 1) the machine configuring the toolchain components: the config machine
455 2) the machine building the toolchain components: the build machine
456 3) the machine running the toolchain: the host machine
457 4) the machine the toolchain is generating code for: the target machine
459 We can most of the time assume that the config machine and the build machine
460 are the same. Most of the time, this will be true. The only time it isn't
461 is if you're using distributed compilation (such as distcc). Let's forget
462 this for the sake of simplicity.
464 So we're left with three machines:
469 Any toolchain will involve those three machines. You can be as pretty sure of
470 this as "2 and 2 are 4". Here is how they come into play:
472 1) build == host == target
473 This is a plain native toolchain, targetting the exact same machine as the
474 one it is built on, and running again on this exact same machine. You have
475 to build such a toolchain when you want to use an updated component, such
476 as a newer gcc for example.
477 crosstool-NG calls it "native".
479 2) build == host != target
480 This is a classic cross-toolchain, which is expected to be run on the same
481 machine it is compiled on, and generate code to run on a second machine,
483 crosstool-NG calls it "cross".
485 3) build != host == target
486 Such a toolchain is also a native toolchain, as it targets the same machine
487 as it runs on. But it is build on another machine. You want such a
488 toolchain when porting to a new architecture, or if the build machine is
489 much faster than the host machine.
490 crosstool-NG calls it "cross-native".
492 4) build != host != target
493 This one is called a canadian-toolchain (*), and is tricky. The three
494 machines in play are different. You might want such a toolchain if you
495 have a fast build machine, but the users will use it on another machine,
496 and will produce code to run on a third machine.
497 crosstool-NG calls it "canadian".
499 crosstool-NG can build all these kinds of toolchains (or is aiming at it,
502 (*) The term Canadian Cross came about because at the time that these issues
503 were all being hashed out, Canada had three national political parties.
504 http://en.wikipedia.org/wiki/Cross_compiler
511 Internally, crosstool-NG is script-based. To ease usage, the frontend is
517 The entry point to crosstool-NG is the Makefile script "ct-ng". Calling this
518 script with an action will act exactly as if the Makefile was in the current
519 working directory and make was called with the action as rule. Thus:
522 is equivalent to having the Makefile in CWD, and calling:
525 Having ct-ng as it is avoids copying the Makefile everywhere, and acts as a
528 ct-ng loads sub- Makefiles from the library directory $(CT_LIB_DIR), as set up
529 at configuration time with ./configure.
531 ct-ng also searches for config files, sub-tools, samples, scripts and patches in
532 that library directory.
534 Because of a stupid make behavior/bug I was unable to track down, implicit make
535 rules are disabled: installing with --local would triger those rules, and mconf
541 The kconfig language is a hacked version, vampirised from the Linux kernel
542 (http://www.kernel.org/), and (heavily) adapted to my needs.
544 The list of the most notable changes (at least the ones I remember) follows:
545 - the CONFIG_ prefix has been replaced with CT_
546 - a leading | in prompts is skipped, and subsequent leading spaces are not
548 - otherwise leading spaces are silently trimmed
550 The kconfig parsers (conf and mconf) are not installed pre-built, but as
551 source files. Thus you can have the directory where crosstool-NG is installed,
552 exported (via NFS or whatever) and have clients with different architectures
553 use the same crosstool-NG installation, and most notably, the same set of
556 Architecture-specific |
557 ----------------------+
559 Note: this chapter is not really well written, and might thus be a little bit
560 complex to understand. To get a better grasp of what an architecture is, the
561 reader is kindly encouraged to look at the "arch/" sub-directory, and to the
562 existing architectures to see how things are laid out.
564 An architecture is defined by:
566 - a human-readable name, in lower case letters, with numbers as appropriate.
567 The underscore is allowed; space and special characters are not.
569 - a file in "config/arch/", named after the architecture's name, and suffixed
571 Eg.: config/arch/arm.in
572 - a file in "scripts/build/arch/", named after the architecture's name, and
574 Eg.: scripts/build/arch/arm.sh
576 The architecture's ".in" file API:
577 > the config option "ARCH_%arch%" (where %arch% is to be replaced with the
578 actual architecture name).
579 That config option must have *neither* a type, *nor* a prompt! Also, it can
580 *not* depend on any other config option (EXPERIMENTAL is managed as above).
584 defines a (terse) help entry for this architecture:
588 The ARM architecture.
590 selects adequate associated config options.
591 Note: 64-bit architectures *shall* select ARCH_64
594 select ARCH_SUPPORTS_BOTH_ENDIAN
595 select ARCH_DEFAULT_LE
597 The ARM architecture.
602 The x86_64 architecture.
604 > other target-specific options, at your discretion. Note however that to
605 avoid name-clashing, such options shall be prefixed with "ARCH_%arch%",
606 where %arch% is again replaced by the actual architecture name.
607 (Note: due to historical reasons, and lack of time to clean up the code,
608 I may have left some config options that do not completely conform to
609 this, as the architecture name was written all upper case. However, the
610 prefix is unique among architectures, and does not cause harm).
612 The architecture's ".sh" file API:
613 > the function "CT_DoArchTupleValues"
616 - all variables from the ".config" file,
617 - the two variables "target_endian_eb" and "target_endian_el" which are
618 the endianness suffixes
619 + return value: 0 upon success, !0 upon failure
622 - the environment variable CT_TARGET_ARCH
624 the architecture part of the target tuple.
625 Eg.: "armeb" for big endian ARM
629 - the environment variable CT_TARGET_SYS
631 the sytem part of the target tuple.
632 Eg.: "gnu" for glibc on most architectures
633 "gnueabi" for glibc on an ARM EABI
635 - for glibc-based toolchain: "gnu"
636 - for uClibc-based toolchain: "uclibc"
639 - the environment variable CT_KERNEL_ARCH
641 the architecture name as understandable by the Linux kernel build
643 Eg.: "arm" for an ARM
644 "powerpc" for a PowerPC
650 - the environment variables to configure the cross-gcc (defaults)
651 - CT_ARCH_WITH_ARCH : the gcc ./configure switch to select architecture level ( "--with-arch=${CT_ARCH_ARCH}" )
652 - CT_ARCH_WITH_ABI : the gcc ./configure switch to select ABI level ( "--with-abi=${CT_ARCH_ABI}" )
653 - CT_ARCH_WITH_CPU : the gcc ./configure switch to select CPU instruction set ( "--with-cpu=${CT_ARCH_CPU}" )
654 - CT_ARCH_WITH_TUNE : the gcc ./configure switch to select scheduling ( "--with-tune=${CT_ARCH_TUNE}" )
655 - CT_ARCH_WITH_FPU : the gcc ./configure switch to select FPU type ( "--with-fpu=${CT_ARCH_FPU}" )
656 - CT_ARCH_WITH_FLOAT : the gcc ./configure switch to select floating point arithmetics ( "--with-float=soft" or /empty/ )
659 - the environment variables to pass to the cross-gcc to build target binaries (defaults)
660 - CT_ARCH_ARCH_CFLAG : the gcc switch to select architecture level ( "-march=${CT_ARCH_ARCH}" )
661 - CT_ARCH_ABI_CFLAG : the gcc switch to select ABI level ( "-mabi=${CT_ARCH_ABI}" )
662 - CT_ARCH_CPU_CFLAG : the gcc switch to select CPU instruction set ( "-mcpu=${CT_ARCH_CPU}" )
663 - CT_ARCH_TUNE_CFLAG : the gcc switch to select scheduling ( "-mtune=${CT_ARCH_TUNE}" )
664 - CT_ARCH_FPU_CFLAG : the gcc switch to select FPU type ( "-mfpu=${CT_ARCH_FPU}" )
665 - CT_ARCH_FLOAT_CFLAG : the gcc switch to choose floating point arithmetics ( "-msoft-float" or /empty/ )
666 - CT_ARCH_ENDIAN_CFLAG : the gcc switch to choose big or little endian ( "-mbig-endian" or "-mlittle-endian" )
671 - the environement variables to configure the core and final compiler, specific to this architecture:
672 - CT_ARCH_CC_CORE_EXTRA_CONFIG : additional, architecture specific core gcc ./configure flags
673 - CT_ARCH_CC_EXTRA_CONFIG : additional, architecture specific final gcc ./configure flags
678 - the architecture-specific CFLAGS and LDFLAGS:
679 - CT_ARCH_TARGET_CLFAGS
680 - CT_ARCH_TARGET_LDFLAGS
684 You can have a look at "config/arch/arm.in" and "scripts/build/arch/arm.sh" for
685 a quite complete example of what an actual architecture description looks like.
690 A kernel is defined by:
692 - a human-readable name, in lower case letters, with numbers as appropriate.
693 The underscore is allowed; space and special characters are not (although
694 they are internally replaced with underscores.
695 Eg.: linux, bare-metal
696 - a file in "config/kernel/", named after the kernel name, and suffixed with
698 Eg.: config/kernel/linux.in, config/kernel/bare-metal.in
699 - a file in "scripts/build/kernel/", named after the kernel name, and suffixed
701 Eg.: scripts/build/kernel/linux.sh, scripts/build/kernel/bare-metal.sh
703 The kernel's ".in" file must contain:
704 > an optional lines containing exactly "# EXPERIMENTAL", starting on the
705 first column, and without any following space or other character.
706 If this line is present, then this kernel is considered EXPERIMENTAL,
707 and correct dependency on EXPERIMENTAL will be set.
709 > the config option "KERNEL_%kernel_name%" (where %kernel_name% is to be
710 replaced with the actual kernel name, with all special characters and
711 spaces replaced by underscores).
712 That config option must have *neither* a type, *nor* a prompt! Also, it can
713 *not* depends on EXPERIMENTAL.
714 Eg.: KERNEL_linux, KERNEL_bare_metal
716 defines a (terse) help entry for this kernel.
718 config KERNEL_bare_metal
720 Build a compiler for use without any kernel.
722 selects adequate associated config options.
724 config KERNEL_bare_metal
727 Build a compiler for use without any kernel.
729 > other kernel specific options, at your discretion. Note however that, to
730 avoid name-clashing, such options should be prefixed with
731 "KERNEL_%kernel_name%", where %kernel_name% is again tp be replaced with
732 the actual kernel name.
733 (Note: due to historical reasons, and lack of time to clean up the code,
734 I may have left some config options that do not completely conform to
735 this, as the kernel name was written all upper case. However, the prefix
736 is unique among kernels, and does not cause harm).
738 The kernel's ".sh" file API:
739 > is a bash script fragment
741 > defines the function CT_DoKernelTupleValues
742 + see the architecture's CT_DoArchTupleValues, except for:
743 + set the environment variable CT_TARGET_KERNEL, the kernel part of the
745 + return value: ignored
747 > defines the function "do_kernel_get":
750 - all variables from the ".config" file.
751 + return value: 0 for success, !0 for failure.
752 + behavior: download the kernel's sources, and store the tarball into
753 "${CT_TARBALLS_DIR}". To this end, a functions is available, that
754 abstracts downloading tarballs:
755 - CT_DoGet <tarball_base_name> <URL1 [URL...]>
756 Eg.: CT_DoGet linux-2.6.26.5 ftp://ftp.kernel.org/pub/linux/kernel/v2.6
757 Note: retrieving sources from svn, cvs, git and the likes is not supported
758 by CT_DoGet. You'll have to do this by hand, as it is done for eglibc in
759 "scripts/build/libc/eglibc.sh"
761 > defines the function "do_kernel_extract":
764 - all variables from the ".config" file,
765 + return value: 0 for success, !0 for failure.
766 + behavior: extract the kernel's tarball into "${CT_SRC_DIR}", and apply
767 required patches. To this end, a function is available, that abstracts
769 - CT_ExtractAndPatch <tarball_base_name>
770 Eg.: CT_ExtractAndPatch linux-2.6.26.5
772 > defines the function "do_kernel_headers":
775 - all variables from the ".config" file,
776 + return value: 0 for success, !0 for failure.
777 + behavior: install the kernel headers (if any) in "${CT_SYSROOT_DIR}/usr/include"
779 > defines any kernel-specific helper functions
780 These functions, if any, must be prefixed with "do_kernel_%CT_KERNEL%_",
781 where '%CT_KERNEL%' is to be replaced with the actual kernel name, to avoid
784 You can have a look at "config/kernel/linux.in" and "scripts/build/kernel/linux.sh"
785 as an example of what a complex kernel description looks like.
787 Adding a new version of a component |
788 ------------------------------------+
790 When a new component, such as the Linux kernel, gcc or any other is released,
791 adding the new version to crosstool-NG is quite easy. There is a script that
792 will do all that for you:
793 scripts/addToolVersion.sh
795 Run it with no option to get some help.
800 To Be Written later...