Re: [PATCH 17/17] Add RISC-V to build-many-glibcs.py

[Joseph Myers <joseph at codesourcery dot com>]

On Wed, 24 Jan 2018, Palmer Dabbelt wrote:

> diff --git a/scripts/build-many-glibcs.py b/scripts/build-many-glibcs.py
> index 28c04e66fd52..e3113599beb1 100755
> --- a/scripts/build-many-glibcs.py
> +++ b/scripts/build-many-glibcs.py
> @@ -329,6 +329,12 @@ class Context(object):
>                          os_name='linux-gnuspe',
>                          variant='e500v1',
>                          gcc_cfg=['--disable-multilib', '--enable-secureplt'])
> +        self.add_config(arch='riscv64',
> +                        os_name='linux-gnu',
> +                        glibcs=[{'variant': 'rv64imafdc-lp64d',
> +                                 'ccopts': '-march=rv64imafdc -mabi=lp64d'},
> +                                {'variant': 'rv64imac-lp64',
> +                                 'ccopts': '-march=rv64imac -mabi=lp64'}])

Are you sure this actually works with this version of the port, and 
current upstream GCC?

In patch 16, in this version of the port, the preconfigure script 
disallows soft-float, "glibc does not yet support systems without the F 
extension".  Apart from a few other places in the port with soft-float 
support (again, the port should be consistent about what is or is not 
supported - either have the soft-float support, or not include the code at 
all because it can't be tested - of course most places are actually 
testing for the ABI, but it seems there are a few testing __riscv_flen), 
as I understand it -march=rv64imac means soft-float so wouldn't build 
given patch 16.  *And* GCC's t-linux-multilib looks like it expects both 
32-bit and 64-bit, hard-float and soft-float ABI multilibs:

MULTILIB_REQUIRED = march=rv32imac/mabi=ilp32 \
march=rv32imafdc/mabi=ilp32d \
march=rv64imac/mabi=lp64 \
march=rv64imafdc/mabi=lp64d

So I'd expect the second GCC build to run into problems when only RV64 
multilibs of glibc but not RV32 ones have been built, because it would try 
to build the RV32 shared libraries of libgcc, libstdc++ etc., which depend 
on glibc having been built.

-- 
Joseph S. Myers
joseph@codesourcery.com