Re: @CPP_FOR_BUILD@ problem since binutils-2.38

[Alan Modra <amodra@gmail.com>]

On Mon, Oct 10, 2022 at 03:50:31PM +0900, Tsukasa OI wrote:
> On 2022/10/10 9:43, Alan Modra via Binutils wrote:
> > To merge with gcc's copy of configure.ac we need to revert changes to
> > configure.ac in the following gcc commits:
> > dc832fb39fc0 2022-08-25
> > fc259b522c0f 2022-06-25
> > Then reapply configure.ac changes in binutils from these binutils
> > commits:
> > 50ad1254d503 2021-01-09
> > bb368aad297f 2022-03-11
> > e5f2f7d901ee 2022-07-26
> > 2cac01e3ffff 2022-09-26
> > Plus copy over gcc's config/ax_cxx_compile_stdcxx.m4, then regenerate
> > configure.  configure.ac diff from current binutila shown below.
> 
> Hmm, generally good (I wasn't sure that applying GCC's configuration
> script's DSYMUTIL and OTOOL substitution is safe enough [because I don't
> have any modern Mac].  As long as this is tested on the GCC side, this
> change is okay).
> 
> One thing I have to point out is, this commit creates an unsubstituted
> variable: PKG_CONFIG_PATH.

Commit 2cac01e3ffff you mean.  Fangrui, would you take a look please?

>  So, we have to create a GCC patch to subst
> this and sync with Binutils.  Am I right?

At one time there was interest in combined binutils+gcc builds, but I
think that is no longer supported by gcc.  At least not actively
supported.  That naturally results in less interest by gcc maintainers
in binutils specific top level patches.  Despite that, some of the gcc
maintainers have done a stellar job in the past of handling these sort
of patches.  However, I know at least one of the four binutils
configure patches I identified has been submitted to the gcc project
already.  No OK given.  I can't tell people to submit patches to gcc
that are ignored, and I also can't reasonably expect gcc folk to
review binutils or gdb patches.  If we're going to continue with
shared top level files, with the gcc repo being the master, then I
think the gcc project needs to extend review and commit rights to
binutils and gdb maintainers for areas that affect binutils and gdb.

-- 
Alan Modra
Australia Development Lab, IBM