[build] Move unwinder to toplevel libgcc (v2)

[Joseph S. Myers]

On Wed, 10 Aug 2011, Rainer Orth wrote:

> "Joseph S. Myers" <joseph@codesourcery.com> writes:
> 
> > This appears to have brought back PR 26478, build failure with readonly 
> > source directory:
> >
> > cp unwind.h ../../.././gcc/include/unwind.h
> > cp: cannot create regular file `../../.././gcc/include/unwind.h': Permission denied
> > make[4]: *** [install-unwind_h] Error 1
> 
> This is strange: they copy explicitly goes into $(gcc_objdir): from
> libgcc/Makefile.in:
> 
> install-unwind_h:
>         cp unwind.h $(gcc_objdir)/include/unwind.h
>         chmod a+r $(gcc_objdir)/include/unwind.h
> 
> For an in-tree build, the source directory cannot be read-only, for a
> VPATH build I don't see how this can happen.  Could you please check?

This is a VPATH build and the issue is that the *file* unwind.h is 
readonly having been copied from a readonly source (and install-unwind_h 
must, I suppose, end up getting called more than once so that the second 
copy tries to copy over a readonly file; the 26478 fix was to remove the 
target of the copy with rm -f before copying).

-- 
Joseph S. Myers
joseph@codesourcery.com