The short answer for why we need to do this is so we can consistently do
`#include "nix/..."`. Without this change, there are ways to still make
that work, but they are hacky, and they have downsides such as making it
harder to make sure headers from the wrong Nix library (e..g.
`libnixexpr` headers in `libnixutil`) aren't being used.
The C API alraedy used `nix_api_*`, so its headers are *not* put in
subdirectories accordingly.
Progress on #7876
We resisted doing this for a while because it would be annoying to not
have the header source file pairs close by / easy to change file
path/name from one to the other. But I am ameliorating that with
symlinks in the next commit.
(cherry picked from commit f3e1c47f47)
This fixes a few of the property tests, now that the property tests
are actually generating arbitrary data - some of that data now
requiring experimental features to function properly.
(cherry picked from commit c82ef825d4)
The underlying issue is that debugger code path was
calling PosTable::operator[] in each eval method.
This has become incredibly expensive since 5d9fdab3de.
While we are it it, I've reworked the code to
not use std::shared_ptr where it really isn't necessary.
As I've documented in previous commits, this is actually
more a workaround for recursive header dependencies now
and is only necessary in `error.hh` code.
Some ad-hoc benchmarking:
After this commit:
```
Benchmark 1: nix eval nixpkgs#hello --impure --ignore-try --no-eval-cache --debugger
Time (mean ± σ): 784.2 ms ± 7.1 ms [User: 561.4 ms, System: 147.7 ms]
Range (min … max): 773.5 ms … 792.6 ms 10 runs
```
On master 3604c7c51:
```
Benchmark 1: nix eval nixpkgs#hello --impure --ignore-try --no-eval-cache --debugger
Time (mean ± σ): 22.914 s ± 0.178 s [User: 18.524 s, System: 4.151 s]
Range (min … max): 22.738 s … 23.290 s 10 runs
```
(cherry picked from commit adbd08399c)
All of this code doesn't actually depend on anything from
libexpr. Because Pos is so tigtly coupled with Error, it
makes sense to have in the same library.
(cherry picked from commit a53b184e63)
It's not very clear what the ownership model is here, but one thing
is certain: `.up` can't be destroyed before the StaticEnv that refers
to it is.
Changing a non-owning pointer to taking shared ownership of the parent
`StaticEnv` prevents the `.up` from being freed.
I'm not a huge fan of the inverted ownership, where child `StaticEnv`
takes a refcount of the parent, but this seems like the least intrusive
way to fix the use-after-free.
This shouldn't cause any shared_ptr cycles to appear (hopefully).
Note that in pure mode, we don't need to use the union FS even when
using a chroot store, since the user shouldn't have access to the
physical /nix/store.
E.g. in a derivation attribute `foo = ./bar`, if ./bar is a symlink,
we should copy the symlink to the store, not its target. This restores
the behaviour of Nix <= 2.19.
This is a big step documenting the store layer on its own, separately from the evaluator (and `builtins.derivation`).
Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
