From GCC's standpoint ARC's multilib items are defined by "mcpu" values
which we have quite a few and for all of them might be built optimized
cross-toolchain.
From Glibc's standpoint multilib is just multi-ABI [1] and so very limited
versions are supposed to co-exist (e.g. arc700 & archs).
Here we force Glibc to install libraries in GCC's multilib folder to create
a universal cross-toolchain that has libs optimized for multiple CPU types.
But note we only need to mess with installation paths in case of real
multilib, otherwise we keep default "lib/" paths so that GCC finds default
(the one and only) libs where it expects them to be.
Also here we add a sample which allows to build universal Glibc Linux
toolchain for ARC.
[1] https://sourceware.org/ml/libc-alpha/2019-06/msg00018.html
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
... parts of the config tuple. While here, remove parts that are
setting portions of the target tuple to a value that's already
the default.
Signed-off-by: Alexey Neyman <stilor@att.net>
In case we build for ARC core which has no support of atomic ops among
other things we need to configure libc to use Linux kernel helper to emulate
HS atomic ops. This is done with disabling of CONFIG_ARC_HAS_ATOMICS in uClibc.
Currently we __remove__ this option from .config but this makes no sense as
its default state is "y" so we need to explicitly disable it instead.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Synopsys' DesignWare ARC Processors are a family of 32-bit CPUs
that SoC designers can optimize for a wide range of uses,
from deeply embedded to high-performance host applications in a variety
of market segments.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
