The darwin_stop_world implementation is slightly different. sp goes to
altstack_lo instead of lo in this case. Assuming that is an
implementation detail.
But the fix is the same, when we detect alstack_lo outside of the
expected stack range, we reset it to hi - stack_limit.
Here stack_limit is calculated with pthread_get_stacksize_np since
that is the BSD equivalent to pthread_attr_getstacksize.
A [recent-ish change](https://github.com/NixOS/nix/pull/6676) logs a warning when a potentially counterintuitive situation happens.
This now causes the multi-user installer to [emit a warning](https://github.com/NixOS/nixpkgs/issues/189043) when it's doing
the "seed the Nix database" step via a low-level `nix-store --load-db` invocation.
`nix-store` functionality implementations don't actually use profiles or channels or homedir as far as i can tell. So why are we
hitting this code at all?
Well, the current command approach for functionality here builds a [fat `nix` binary](https://github.com/NixOS/nix/blob/master/src/nix/local.mk#L23-L26) which has _all_ the functionality of
previous individual binaries (nix-env, nix-store, etc) bundled in, then [uses the invocation name](https://github.com/NixOS/nix/blob/master/src/nix/main.cc#L274-L277) to select the
set of commands to expose. `nix` itself has this behavior, even when just trying to parse the (sub)command and arguments:
```
dave @ davembp2
$ nix
error: no subcommand specified
Try 'nix --help' for more information.
dave @ davembp2
$ sudo nix
warning: $HOME ('/Users/dave') is not owned by you, falling back to the one defined in the 'passwd' file
error: no subcommand specified
Try 'nix --help' for more information.
dave @ davembp2
$ HOME=~root sudo nix
error: no subcommand specified
Try 'nix --help' for more information.
```
This behavior can also be seen pretty easily with an arbitrary `nix-store` invocation:
```
dave @ davembp2
$ nix-store --realize
dave @ davembp2
$ sudo nix-store --realize # what installer is doing now
warning: $HOME ('/Users/dave') is not owned by you, falling back to the one defined in the 'passwd' file
dave @ davembp2
$ sudo HOME=~root nix-store --realize # what this PR effectively does
dave @ davembp2
$
```
this simplifies the setup a lot, and avoids weird looking `./file.md`
links showing up.
it also does not show regular URLs any more. currently the command
reference only has few of them, and not showing them in the offline
documentation is hopefully not a big deal.
instead of building more special-case solutions, clumsily preprocessing
the input, or issuing verbal rules on dealing with URLs, should better
be solved sustainably by not rendering relative links in `lowdown`:
https://github.com/kristapsdz/lowdown/issues/105
This was caused by -L calling setLogFormat() again, which caused the
creation of a new progress bar without destroying the old one. So we
had two progress bars clobbering each other.
We should change 'logger' to be a smart pointer, but I'll do that in a
future PR.
Fixes#6931.
98e361ad4c introduced a regression where
previously stored attributes were replaced by placeholders. As a
result, a command like 'nix build nixpkgs#hello' had to be executed at
least twice to get caching.
This code does not seem necessary for suggestions to work.
