[PPL-devel] PPL broken for Canadian-cross builds

[Joseph S. Myers]

On Fri, 20 Mar 2009, Roberto Bagnara wrote:

> Hi Joseph,
> 
> thanks for the detailed explanation.  I admit we always have postoponed the
> issue of cross-compilation... to the point we almost forgot it.  We will
> fix the PPL asap.  Can we come back to you in case we are unsure about which
> defaults can be considered safe?

I can test whether a candidate fixed tarball works (to build PPL and GCC 
in such an environment) in this case; telling what is safe is in general 
difficult without knowing the details of PPL internals and how it is used 
by GCC, and I don't have time right now to go through any differences in 
code generation between different hosts to see if they relate to PPL 
issues (and am not set up to build PPL or GCC directly on Windows to 
compare such a GCC with one built with a cross compiler to i686-mingw32 
target).

> > Would it be possible to have an official 0.10.1 bug-fix release with this
> > fixed (and preferably without changes that would affect the code generated
> > by GCC) for use with GCC 4.4 so that it is possible to enable Graphite in
> > such configurations?
> 
> Work has already started for producing an official PPL 0.11 release.
> This will contain fixes for all the problems we discovered since the release
> of PPL 0.10 (mainly portability ones), a new "formatted output" feature
> that is needed in the MELT branch, plus other improvements, none of which
> affecting the code generated by GCC.  I will write again when we can be
> more precise about the release schedule.

I suggested a minimally fixed 0.10.1 to provide something maximally safe 
to use with 4.4 (or 4.4.1, etc., depending on the timing) without needing 
--disable-ppl-version-check; I'd be wary of explicitly approving multiple 
versions for use with 4.4, or increasing the recommended version from 0.10 
to 0.11, at this late stage.  For development for GCC 4.5, increasing the 
recommended version to 0.11 would seem appropriate.

Unfortunately building with a cross-compiler is so much a normal way of 
building GCC and the libraries it uses to me I didn't think PPL would need 
specific testing with it or that the portability testing of PPL done when 
support for using it was added to GCC would not have included it, so 
didn't test it before now.

-- 
Joseph S. Myers
joseph at codesourcery.com