Re: PG versus libxml2 2.12.x

On 27.01.24 20:04, Tom Lane wrote:
> Buildfarm member caiman has been failing build for a couple weeks now.
> The reason turns out to be that recent libxml2 has decided to throw
> a "const" into the signature required for custom error handlers.
> (API compatibility?  What's that?)
> 
> I don't mind adopting the "const" --- it's a good idea in isolation.
> The trouble is in fixing our code to work with both old and new
> libxml2 versions.  We could thrash around with a configure test or
> something, but I think the most expedient answer is just to insert
> some explicit casts, as shown in the attached.  It's possible though
> that some compilers will throw a cast-away-const warning.  I'm
> not seeing any, but ...

In PL/Tcl, we used to have these CONST84 and CONST86 things, for similar 
reasons.  Maybe that would be another approach.