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ããThe语言c语言编译器JZSearch源码re are two libc libraries commonly used with uClinux. uC-libc and
uClibc. They are quite different despite their similar names. Here is a
quick overview of how they are different.
ããuC-libc is the original library for uClinux. It was based on sources
from the Linux- C library which was part of the ELKs project with m
support added by Jeff Dionne and Kenneth Albanowski. It is a fairly complete
libc implementation, however, some of the API's are a little non-standard
and quite a few common libc routines are not present. Currently it has
stable support for m, ColdFire and ARM (Non-MMU) architectures. It was
primary design goal is to be small and light weight. It does try to conform
to any standards, although its API tries to be compatible with most libcs,
it is not always exactly the same.
ããThe uClinux distribution provides an environment that can compile using
either uC-libc or uClibc depending on your needs. For m and Coldfire
platforms it is generally better to chose uC-libc as it supports shared
libraries and is the most commonly used libc for these CPUs. uClibc also
works quite well with almost all platforms supported by the distribution.
Which libc you choose to use will be decided by your requirements
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Linaro prebuilt toolchain does support both hard and soft floating
point. You can get it from /linaro-toolchain-binaries/+milestone/. try: ./arm-linux-gnueabihf-gcc -print-multi-lib
The default configure is --with-arch=armv7-a --with-tune=cortex-a9
--with-fpu=vfpv3-d --with-float=hard --with-mode=thumb
To use soft floating, you need options: -marm -march=armv4t -mfloat-abi=soft.
In your case, please try to change -march=armv5 to "-march=armv4t"
If you want to change to configure to cortex-a8 and armv5. You need
* Change cortex-a9 to cortex-a8 in
samples/linaro-arm-linux-gnueabihf/crosstool.config
* Change armv4t to armv5 in
contrib/linaro/patches/gcc/linaro-4.7-./multilib.patch,
Then follow the instructions to rebuild the toolchain
(contrib/linaro/doc/README.txt)
BTW: crosstool-ng-linaro does not support multilib for eglibc. It uses
the prebuilt sysroot from Ubuntu Precise. If it does not work for you,
please use the latest crosstool-ng from http://crosstool-ng.org/.