This fixes a segfault on infinite function call recursion (rather than
infinite thunk recursion) by tracking the function call depth in
`EvalState`.
Additionally, to avoid printing extremely long stack traces, stack
frames are now deduplicated, with a `(19997 duplicate traces omitted)`
message. This should only really be triggered in infinite recursion
scenarios.
Before:
$ nix-instantiate --eval --expr '(x: x x) (x: x x)'
Segmentation fault: 11
After:
$ nix-instantiate --eval --expr '(x: x x) (x: x x)'
error: stack overflow
at «string»:1:14:
1| (x: x x) (x: x x)
| ^
$ nix-instantiate --eval --expr '(x: x x) (x: x x)' --show-trace
error:
… from call site
at «string»:1:1:
1| (x: x x) (x: x x)
| ^
… while calling anonymous lambda
at «string»:1:2:
1| (x: x x) (x: x x)
| ^
… from call site
at «string»:1:5:
1| (x: x x) (x: x x)
| ^
… while calling anonymous lambda
at «string»:1:11:
1| (x: x x) (x: x x)
| ^
… from call site
at «string»:1:14:
1| (x: x x) (x: x x)
| ^
(19997 duplicate traces omitted)
error: stack overflow
at «string»:1:14:
1| (x: x x) (x: x x)
| ^
Previously, IFDs would be built within the eval store, even though one
is typically using `--eval-store` precisely to *avoid* local builds.
Because the resulting Nix expression must be copied back to the eval
store in order to be imported, this requires the eval store to trust
the build store's signatures.
On macOS in the `nix develop` shell, `make
tests/functional/logging.sh.test` errors:
++(logging.sh:18) mktemp
+(logging.sh:18) builder=/var/folders/z5/fclwwdms3r1gq4k4p3pkvvc00000gn/T/tmp.StuabKUhMh
+(logging.sh:19) echo -e '#!/bin/sh\nmkdir $out'
+++(logging.sh:22) mktemp -d
++(logging.sh:22) nix-build -E 'with import ./config.nix; mkDerivation { name = "fnord"; builder = /var/folders/z5/fclwwdms3r1gq4k4p3pkvvc00000gn/T/tmp.StuabKUhMh; }' --out-link /var/folders/z5/fclwwdms3r1gq4k4p3pkvvc00000gn/T/tmp.oaKcy0NXqC/result
error:
… while calling the 'derivationStrict' builtin
at <nix/derivation-internal.nix>:9:12:
8|
9| strict = derivationStrict drvAttrs;
| ^
10|
… while evaluating derivation 'fnord'
whose name attribute is located at «string»:1:42
… while evaluating attribute 'args' of derivation 'fnord'
at /Users/wiggles/nix/tests/functional/config.nix:23:7:
22| builder = shell;
23| args = ["-e" args.builder or (builtins.toFile "builder-${args.name}.sh" ''
| ^
24| if [ -e "$NIX_ATTRS_SH_FILE" ]; then source $NIX_ATTRS_SH_FILE; fi;
error: path '/var' is a symlink
+(logging.sh:22) outp=
++(logging.sh:22) onError
++(/Users/wiggles/nix/tests/functional/common/vars-and-functions.sh:237) set +x
logging.sh: test failed at:
main in logging.sh:22
This is because `mktemp` returns a path like
`/var/folders/z5/fclwwdms3r1gq4k4p3pkvvc00000gn/T/tmp.qDY24l6bIM`,
where `/var` is a symlink to `/private/var`.
Then, we attempt to use that path as a `builder`, which errors because
symlinks are impure or whatever.
Anyways, we can fix this by using `realpath "$(mktemp)"` instead of
`mktemp` directly.
NB: This error doesn't seem to happen when I run the tests through `nix
flake check`. I'm not sure if Nix does something to `TMP` in that case.
`nix flake check` had these warnings:
trace: warning: Module argument `nodes.client.config` is deprecated. Use `nodes.client` instead.
trace: warning: Module argument `nodes.client.config` is deprecated. Use `nodes.client` instead.
trace: warning: The option `services.openssh.permitRootLogin' defined in `/nix/store/3m3hfpmbjdf4w39qfjami7ljhvhczay1-source/tests/nixos/nix-copy.nix' has been renamed to `services.openssh.settings.PermitRootLogin'.
trace: warning: Module argument `nodes.http_dns.config` is deprecated. Use `nodes.http_dns` instead.
trace: warning: Module argument `nodes.github.config` is deprecated. Use `nodes.github` instead.
trace: warning: Module argument `nodes.sourcehut.config` is deprecated. Use `nodes.sourcehut` instead.
This keeps hint messages, source location information, and source code
snippets grouped together, while making stack traces shorter (so that
more stack frames can be viewed on the same terminal).
Before:
error:
… while evaluating the attribute 'body'
at /Users/wiggles/nix/tests/functional/lang/eval-fail-assert.nix:4:3:
3|
4| body = x "x";
| ^
5| }
… from call site
at /Users/wiggles/nix/tests/functional/lang/eval-fail-assert.nix:4:10:
3|
4| body = x "x";
| ^
5| }
… while calling 'x'
at /Users/wiggles/nix/tests/functional/lang/eval-fail-assert.nix:2:7:
1| let {
2| x = arg: assert arg == "y"; 123;
| ^
3|
error: assertion '(arg == "y")' failed
at /Users/wiggles/nix/tests/functional/lang/eval-fail-assert.nix:2:12:
1| let {
2| x = arg: assert arg == "y"; 123;
| ^
3|
After:
error:
… while evaluating the attribute 'body'
at /Users/wiggles/nix/tests/functional/lang/eval-fail-assert.nix:4:3:
3|
4| body = x "x";
| ^
5| }
… from call site
at /Users/wiggles/nix/tests/functional/lang/eval-fail-assert.nix:4:10:
3|
4| body = x "x";
| ^
5| }
… while calling 'x'
at /Users/wiggles/nix/tests/functional/lang/eval-fail-assert.nix:2:7:
1| let {
2| x = arg: assert arg == "y"; 123;
| ^
3|
error: assertion '(arg == "y")' failed
at /Users/wiggles/nix/tests/functional/lang/eval-fail-assert.nix:2:12:
1| let {
2| x = arg: assert arg == "y"; 123;
| ^
3|
`eval-system` option overrides just the value of `builtins.currentSystem`.
This is more useful than overriding `system` since you can build these
derivations on remote builders which can work on the given system.
Co-authored-by: John Ericson <John.Ericson@Obsidian.Systems>
Co-authored-by: Valentin Gagarin <valentin.gagarin@tweag.io>
It works with both `ssh://` and `ssh-ng://` now since #9600 (and
`ssh-ng:// didn't work before that).
Also, by making the two tests share code, we nudge ourselves towards
making sure there is feature parity.
I don't love the way this code looks. There are two larger problems:
- eval, build/scratch, destination stores (#5025) should have different
types to reflect the fact that they are used for different purposes
and those purposes correspond to different operations. It should be
impossible to "use the wrong store" in my cases.
- Since drvs can end up in both the eval and build/scratch store, we
should have some sort of union/layered store (not on the file sytem
level, just conceptual level) that allows accessing both. This would
get rid of the ugly "check both" boilerplate in this PR.
Still, it might be better to land this now / soon after minimal cleanup,
so we have a concrete idea of what problem better abstractions are
supposed to solve.
* Print the value in `error: cannot coerce` messages
This extends the `error: cannot coerce a TYPE to a string` message
to print the value that could not be coerced. This helps with debugging
by making it easier to track down where the value is being produced
from, especially in errors with deep or unhelpful stack traces.
Co-authored-by: Valentin Gagarin <valentin.gagarin@tweag.io>
This includes position information in more places, making debugging
easier.
Before:
```
$ nix-instantiate --show-trace --eval tests/functional/lang/eval-fail-using-set-as-attr-name.nix
error:
… while evaluating an attribute name
at «none»:0: (source not available)
error: value is a set while a string was expected
```
After:
```
error:
… while evaluating an attribute name
at /pwd/lang/eval-fail-using-set-as-attr-name.nix:5:10:
4| in
5| attr.${key}
| ^
6|
error: value is a set while a string was expected
```
In the process, partially undo e89b5bd0bf
in that the ancient < 2.4 version is now supported again by the
serializer again. `LegacySSHStore`, instead of also asserting that the
version is at least 4, just checks that `narHash` is set.
This allows us to better test the serializer in isolation for both
versions (< 4 and >= 4).