Re: git: 24fd63e0970f - main - mips: Don't set __NO_TLS to disable some uses of TLS.

[Brandon Bergren]

On Thu, Feb 18, 2021, at 3:07 PM, Jessica Clarke wrote:
> > But, I wonder, what does CALL_ELF mean?  Is it for old 64bit PowerPC ABI,
> > that was abandoned with the switch to ELFv2?
> 
> Yes, _CALL_ELF == 2 for ELFv2. I highly doubt the defines were needed
> for the ELFv1 ABI, but they're especially redundant now. Presumably
> David's original fixed commit[1] added powerpc64 to that list because
> TLS wasn't yet supported in LLVM; that happened later in 2012 and our
> wiki changed it to being implemented in December 2012[2]. So I suspect
> it should have been deleted 8 years ago.

FreeBSD 13 will be the first ELFv2 release. FreeBSD 12 and below are ELFv1.

The reason for the line was to avoid breaking things during the development period for ELFv2. Switching TLS on was one of the things I did at the same time as the official ELFv2 transition. See 2db975b0eb0f3378a39d63eeabe4e3617f4557f0.

This is NOT an 8 year old change, but I believe it can go away in HEAD as long as the change isn't MFC'd to 12 or earlier.

-- 
  Brandon Bergren
  bdragon at FreeBSD.org