[parisc-linux] We need our own libgcc-compat for a leaked __clz_tab

[parisc-linux] We need our own libgcc-compat for a leaked __clz_tab

[Carlos O'Donell]

PA,

Problem:

- GCC used to export a symbol for __clz_tab (GLOBAL DEFAULT)
- Everything in debian is being built with newer tools (GCC 3.2).
- Symbol is no longer leaked (LOCAL HIDDEN)
- Libraries that had the leadked symbol are rebuilt (e.g. libcrypto)
- Binaries that had relocations against the symbol are failing (e.g.
  wget)

Solution:

- Create a libgcc-compat in glibc for the symbol __clz_tab
	= Various arches have them for certain symbols that were leaked
	= from GCC when we the GNU tools didn't have ".hidden"
	= So examples exist...
- Test the solution to see that atleast "wget" works.
- Put it into Debians glibc as a dpatch.
- Submit upstream for fame and glory.

I'm writing a paper and doing research until Saturday.

If someone feels gutsy enough to attempt a fix, please have at it... 
If not, it's currently the highest priority item on my TODO.

Cheers,
Carlos.

Re: [parisc-linux] We need our own libgcc-compat for a leaked __clz_tab

[John David Anglin]

> Problem:
> 
> - GCC used to export a symbol for __clz_tab (GLOBAL DEFAULT)
> - Everything in debian is being built with newer tools (GCC 3.2).
> - Symbol is no longer leaked (LOCAL HIDDEN)
> - Libraries that had the leadked symbol are rebuilt (e.g. libcrypto)
> - Binaries that had relocations against the symbol are failing (e.g.
>   wget)
> 
> Solution:
> 
> - Create a libgcc-compat in glibc for the symbol __clz_tab
> 	= Various arches have them for certain symbols that were leaked
> 	= from GCC when we the GNU tools didn't have ".hidden"
> 	= So examples exist...
> - Test the solution to see that atleast "wget" works.
> - Put it into Debians glibc as a dpatch.
> - Submit upstream for fame and glory.

As I said, this is a generic problem affecting all GCC ports.  The
correct solution probably isn't adding the symbol to a PA specific
libgcc-compat in glibc.  I think the matter needs discussion on
gcc@gcc.gnu.org.  I'm not sure if there is a reason for hiding this
symbol.  I would file a GCC PR.

Dave
-- 
J. David Anglin                                  dave.anglin@nrc-cnrc.gc.ca
National Research Council of Canada              (613) 990-0752 (FAX: 952-6605)