Re: [PATCH] contracts: Stop relying on mangling for naming .pre/.post clones

[Jason Merrill <jason@redhat.com>]

On 12/15/22 13:00, Arsen Arsenović wrote:
> Hi Jason,
> 
> Jason Merrill <jason@redhat.com> writes:
> 
>> On 12/10/22 08:13, Arsen Arsenović wrote:
>>> If the mangler is relied on, functions with extern "C" on them emit multiple
>>> definitions of the same name.
>>
>> But doing it here interferes with lazy mangling.  How about appending the
>> suffix into write_mangled_name instead of write_encoding?  The demangler
>> already expects "clone" suffixes at the end of the mangled name.
> 
> Ah, sorry.  I'm not well versed in the mangler code, so I didn't realize
> (frankly, I was initially surprised when I saw that DECL_ASSEMBLER_NAME
> was set that early, but went with it).  That makes sense.
> 
> How about this?  Tested on x86_64-pc-linux-gnu via check-g++.
> 
> 
> 
> I did run c++filt (afaik, it uses the libiberty demangler) on this
> revision, and I got:
> 
>            .type	f(int) [clone .pre], @function
>    f(int) [clone .pre]:
> 
> out of ``void f(int x) [[ pre: x > 10 ]] {}'', which seems to match your
> description.
> 
> If I understand this right, write_xxx corresponds to xxx in the Itanium
> ABI mangling BNF, in which case, I believe I have the correct spot here.
> In that case, a similar change should happen for coroutines; I think
> Iain was working on that.

> 	* mangle.cc (write_encoding): Move contract pre/post function mangling

It's best to wrap the ChangeLog entry at column 75 so that the extra 
indentation added by git log doesn't push past column 80.

Applied with that change.

Jason