C++ ABI issues

[Jason Merrill]

>>>>> "Benjamin" == Benjamin Kosnik <bkoz@redhat.com> writes:

>> One answer would be to bump the mangling version for non-ia64 targets,
>> so that incompatible code will fail to link.

> Why just non-ia64 targets?

Because for ia64, the ABI is a cross-vendor standard.  If we bumped the
version, we would be incompatible with all other compilers, which would
subvert the entire point of the ABI.

> Won't the major version number change from .3 to .4 in libstdc++-v3
> also prevent linkage?

For code that uses libstdc++, yes.  Perhaps that is true of most programs,
and the problem is minor.

> I'd feel better if there was a better mechanism for testing the C++
> ABI. Thoughts? 

We have a few tests in the testsuite.  I thought that CodeSourcery had more
internally, but I haven't heard about them in quite a while.

Jason