[RFC PATCH] Optionally use -mlong-double-128 by default on {powerpc{,64},s390{,x},sparc,alpha}-linux

[Daniel Jacobowitz]

On Fri, Jan 27, 2006 at 11:58:08AM -0500, Jakub Jelinek wrote:
> For libstdc++.so, the header __asm redirect stuff just won't work,
> C++ doesn't allow that.  But that's not that big deal, I expect
> all distros that switch to glibc 2.4 will switch to 128-bit long double
> and mass rebuild everything.  If someone wants to compile/link a
> -mlong-double-64 program, he can use some compatibility compiler,
> or even just a contemporary gcc configured with --without-long-double-128
> installed in a separate prefix or something.

Are you _trying_ to have a horde of Debian developers lynch you?  Many
commercial distributions operate on the "it's OK to rebuild everything"
principal, but Debian doesn't.

Can you be more specific about which conditions would require a
rebuild?

> But, with shared libraries we need just one library with a given SONAME
> that is backwards compatible, DT_RPATH hacks would just lead to extreme
> insanity and wouldn't really work.
> So, I want to do the symbol versioning part of 1) in libstdc++ too
> (but don't do any header redirections).

The ICC folks at last year's GCC summit talked about a more
C++-friendly way to solve this sort of problem; is that suitable here?
I don't remember whether it could be incrementally adopted.


-- 
Daniel Jacobowitz
CodeSourcery