Re: Compiler ABI changes and XPCOM components

On Mon, 17 Jun 2002 12:08:21 -0700, Doug Turner <[email protected]> wrote:
> It really depends on how much the binary interface is broken.  If the 
> compiler decides to reorders vtables, prebuilt libraries under the old 
> compiler will not work in a xpcom that is compiled under the new compiler.
> 

gcc 3.x is suffiently different to egcs that that won't work. The thunking
is different, to start with, and it goes downhill from there.

On the plus side, theres now a cross platform ABI, which is frozen modulo 
compiler bugs (3.0->3.1 did change stuff, but I don't know if that would 
have affected mozilla)

libstdc++'s ABI isn't frozen, but mozilla doesn't use the STL stuff. We
link to it for operator new + friends, but gcc 3.1 moves that stuff into a
separate library, which will have a stable API, apparently.

Which, in theory, means that once mozilla/netscape/beonix/redhat/etc start 
using gcc3.1.1 for builds, it should, in theory, be stable til gcc 4. In 
theory.

I don't think this will affect people using the old C plugin API, though -
C doesn't have the mangling/etc issues c++ does.

I haven't really tested all of the above options though, so don't take 
what I say as fact...

Bradley