mirror of
https://gitlab.com/buildroot.org/buildroot.git
synced 2026-09-09 07:51:59 -09:00
826f315d5f
Description in uClibc for this optoin is: --->--- bool "Use faster (but larger) generic string functions" default y help Answer Y to use the (tweaked) glibc generic string functions. In general, they are faster (but 3-5K larger) than the base uClibc string functions which are optimized solely for size. Many people will answer Y. --->--- Additional 3-5K of size is not that important if resulting libuClibc.so is of size about 300k. But benefits in terms of performance could be pretty significant. For example on ARC in LMbench we see more than 3 times bump in some tests --->--- libc bcopy unaligned ... 8.39 - 6.76 (UCLIBC_HAS_STRING_GENERIC_OPT=no) 8.39 - 23.86 (UCLIBC_HAS_STRING_GENERIC_OPT=yes) --->--- Also since the option in question is default in uClibc I don't expect if enabled back (it was silently disabled in http://git.buildroot.net/buildroot/commit/?id=cfbf8abc33d86a0cf5c1bb3e0817a22009b7f301 on introduction of NPTL in uClibc by Khem Raj) it to introduce problems. Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Cc: Anton Kolesov <anton.kolesov@synopsys.com> Cc: Peter Korsgaard <peter@korsgaard.com> Cc: Khem Raj <raj.khem@gmail.com> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
To build and use the buildroot stuff, do the following:
1) run 'make menuconfig'
2) select the packages you wish to compile
3) run 'make'
4) wait while it compiles
5) Use your shiny new root filesystem. Depending on which sort of
root filesystem you selected, you may want to loop mount it,
chroot into it, nfs mount it on your target device, burn it
to flash, or whatever is appropriate for your target system.
You do not need to be root to build or run buildroot. Have fun!
Offline build:
==============
In order to do an offline-build (not connected to the net), fetch all
selected source by issuing a
$ make source
before you disconnect.
If your build-host is never connected, then you have to copy buildroot
and your toplevel .config to a machine that has an internet-connection
and issue "make source" there, then copy the content of your dl/ dir to
the build-host.
Building out-of-tree:
=====================
Buildroot supports building out of tree with a syntax similar
to the Linux kernel. To use it, add O=<directory> to the
make command line, E.G.:
$ make O=/tmp/build
And all the output files (including .config) will be located under /tmp/build.
More finegrained configuration:
===============================
You can specify a config-file for uClibc:
$ make UCLIBC_CONFIG_FILE=/my/uClibc.config
And you can specify a config-file for busybox:
$ make BUSYBOX_CONFIG_FILE=/my/busybox.config
To use a non-standard host-compiler (if you do not have 'gcc'),
make sure that the compiler is in your PATH and that the library paths are
setup properly, if your compiler is built dynamically:
$ make HOSTCC=gcc-4.3.orig HOSTCXX=gcc-4.3-mine
Depending on your configuration, there are some targets you can use to
use menuconfig of certain packages. This includes:
$ make HOSTCC=gcc-4.3 linux-menuconfig
$ make HOSTCC=gcc-4.3 uclibc-menuconfig
$ make HOSTCC=gcc-4.3 busybox-menuconfig
Please feed suggestions, bug reports, insults, and bribes back to the
buildroot mailing list: buildroot@buildroot.org