Re: __atomic_test_and_set() and mips o32 - help wanted

On Thu, 20 Nov 2025, Jason Thorpe wrote:

> > There's no quotation of the link failure message referring the missing 
> > symbol, but I'm fairly sure the symbol is a libcall for an unimplemented 
> > feature of libgcc, a part of the compiler, so hacking the compiler is what 
> > indeed is needed (IOW the missing part needs to be added to libgcc if you 
> > do want to avoid emitting LL/SC from the compiler).
> 
> NetBSD could certainly provide that in its own C run-time.

 Unless it's an internal interface with no public API guarantee; I don't 
think there's one for libcalls (although I can provide examples of abuse).  
In that case though you can surely provide a thin wrapper anyway.  It'll 
prevent the compiler from being self-contained, but I reckon there've been 
precedents with proprietary systems already, so that would be no news.  

 Up to you to decide (and whether to put effort into an LL/SC alternative 
in the first place).

  Maciej