Re: [PATCH] build-many-glibcs: Remove no_isolate from SH config

[Joseph Myers <joseph at codesourcery dot com>]

On Tue, 14 Mar 2017, Adhemerval Zanella wrote:

> So I think we have some options:
> 
>   1. Revert the patch and make SH toolchain compile with
>      -fno-isolate-erroneous-paths-dereference (there is no need for
>      add -fno-isolate-erroneous-paths-attribute).
> 
>   2. Build divdi3 for SH explicit with -fno-isolate-erroneous-paths-attribute.
> 
>   3. Port libgcc r205444 with add an __udivmoddi4 implementation for
>      architectures that do not have division instruction (which does not
>      generate a trap for division by 0).
> 
> I would prefer either 2 or 3.

This code is present in glibc purely for compat symbols, which are only 
exported on a limited number of architectures, which do not include SH.  
Thus, I'd favour arranging for the code only to be built at all for those 
architectures (i386 m68k powerpc32 s390-32; ia64 also exports these 
symbols, but from a separate implementation), and not for any other 32-bit 
architecture (and if such architectures need these functions in glibc, 
they will get them from libgcc.a).  That would of course need 
build-many-glibcs tests to make sure it doesn't break anything.

-- 
Joseph S. Myers
joseph@codesourcery.com