1 File.........: 5 - Using the toolchain.txt
2 Copyright....: (C) 2010 Yann E. MORIN <yann.morin.1998@anciens.enib.fr>
3 License......: Creative Commons Attribution Share Alike (CC-by-sa), v2.5
10 Using the toolchain is as simple as adding the toolchain's bin directory in
12 export PATH="${PATH}:/your/toolchain/path/bin"
14 and then using the '--host' tuple to tell the build systems to use your
15 toolchain (if the software package uses the autotools system you should
16 also pass --build, for completeness):
17 ./configure --host=your-host-tuple --build=your-build-tuple
19 make CC=your-host-tuple-gcc
21 make CROSS_COMPILE=your-host-tuple-
24 (Note: in the above example, 'host' refers to the host of your program,
25 not the host of the toolchain; and 'build' refers to the machine where
26 you build your program, that is the host of the toolchain.)
28 It is strongly advised not to use the toolchain sysroot directory as an
29 install directory for your programs/packages. If you do so, you will not be
30 able to use your toolchain for another project. It is even strongly advised
31 that your toolchain is chmod-ed to read-only once successfully build, so that
32 you don't go polluting your toolchain with your programs/packages' files.
34 Thus, when you build a program/package, install it in a separate directory,
35 eg. /your/root. This directory is the /image/ of what would be in the root file
36 system of your target, and will contain all that your programs/packages have
40 The 'populate' script |
41 ----------------------+
43 When your root directory is ready, it is still missing some important bits: the
44 toolchain's libraries. To populate your root directory with those libs, just
46 your-target-tuple-populate -s /your/root -d /your/root-populated
48 This will copy /your/root into /your/root-populated, and put the needed and only
49 the needed libraries there. Thus you don't pollute /your/root with any cruft that
50 would no longer be needed should you have to remove stuff. /your/root always
51 contains only those things you install in it.
53 You can then use /your/root-populated to build up your file system image, a
54 tarball, or to NFS-mount it from your target, or whatever you need.
56 The populate script accepts the following options:
59 Use 'src_dir' as the un-populated root directory.
62 Put the populated root directory in 'dst_dir'.
65 Always add specified libraries.
68 Always add libraries listed in 'file'.
71 Remove 'dst_dir' if it previously existed; continue even if any library
72 specified with -l or -L is missing.
75 Be verbose, and tell what's going on (you can see exactly where libs are
81 See 'your-target-tuple-populate -h' for more information on the options.
83 Here is how populate works:
85 1) performs some sanity checks:
86 - src_dir and dst_dir are specified
88 - unless forced, dst_dir does not exist
91 2) copy src_dir to dst_dir
93 3) add forced libraries to dst_dir
94 - build the list from -l and -L options
95 - get forced libraries from the sysroot (see below for heuristics)
96 - abort on the first missing library, unless -f is specified
98 4) add all missing libraries to dst_dir
99 - scan dst_dir for every ELF files that are 'executable' or
101 - list the "NEEDED Shared library" fields
102 - check if the library is already in dst_dir/lib or dst_dir/usr/lib
103 - if not, get the library from the sysroot
104 - if it's in sysroot/lib, copy it to dst_dir/lib
105 - if it's in sysroot/usr/lib, copy it to dst_dir/usr/lib
106 - in both cases, use the SONAME of the library to create the file
108 - if it was not found in the sysroot, this is an error.