This is because a dynamic_cast<nix::RootArgs *> of a (n-e-j) MyArgs
returns nullptr even though MyArgs has virtual nix::RootArgs as a
parent.
class MyArgs : virtual public nix::MixEvalArgs,
virtual public nix::MixCommonArgs,
virtual nix::RootArgs { ... };
So this should work right?? But it does not. We found out that it's
caused by -fvisibility=hidden in n-e-j, but honestly this code was bad
anyway.
The trivial solution is to simply stop relying on RTTI working properly
here, which is probably better OO architecture anyway. However, I am not
100% confident *this* is sound, since we have this horrible hierarchy:
Args (defines getRoot)
/ | \
RootArgs MixCommonArgs MixEvalArgs
(overrides)
I am not confident that this is guaranteed to resolve from Args always
in the case of this override.
Assertion failed: (res), function getRoot, file src/libutil/args.cc, line 67.
6MyArgsProcess 60503 stopped
* thread #1, queue = 'com.apple.main-thread', stop reason = hit program assert
frame #4: 0x0000000100b1a41c liblixutil.dylib`nix::Args::processArgs(std::__1::list<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>, std::__1::allocator<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>>> const&, bool) [inlined] nix::Args::getRoot(this=0x00000001000d0688) at args.cc:67:5 [opt]
64 std::cout << typeid(*p).name();
65
66 auto * res = dynamic_cast<RootArgs *>(p);
-> 67 assert(res);
68 return *res;
69 }
70
Target 0: (nix-eval-jobs) stopped.
(lldb) p this
(MyArgs *) 0x00000001000d0688
(lldb) p *this
(nix::Args) {
longFlags = size=180 { ... }
shortFlags = size=4 { ... }
expectedArgs = size=1 { ... }
processedArgs = size=0 {}
hiddenCategories = size=1 {
[0] = "Options to override configuration settings"
}
parent = nullptr
}
We also found that if we did this:
class [[gnu::visibility("default")]] RootArgs : virtual public Args
it would work properly (???!). This is of course, very strange, because
objdump -Ct output on liblixexpr.dylib is identical both with and
without it.
Possibly related: https://www.qt.io/blog/quality-assurance/one-way-dynamic_cast-across-library-boundaries-can-fail-and-how-to-fix-it
Fixes: lix-project/nix-eval-jobs#2
Change-Id: I6b9ed968ed56420a9c4d2dffd18999d78c2761bd
Before:
$ nix flake lock --override-input nixpkgs gitlab:simple-nixos-mailserver/nixos-mailserver/nonexistent
fetching git input 'git+file:///home/linus/projects/lix'
fetching gitlab input 'gitlab:simple-nixos-mailserver/nixos-mailserver/nonexistent'
error: [json.exception.type_error.302] type must be string, but is null
After:
$ outputs/out/bin/nix flake lock --override-input nixpkgs gitlab:simple-nixos-mailserver/nixos-mailserver/nonexistent
fetching git input 'git+file:///home/linus/projects/lix'
fetching gitlab input 'gitlab:simple-nixos-mailserver/nixos-mailserver/nonexistent'
error:
… while updating the lock file of flake 'git+file:///home/linus/projects/lix?ref=refs/heads/fix-gitlab-nonexistent&rev=915f16a619a36237a099b9aa9afed6d14ff613b4'
… while updating the flake input 'nixpkgs'
… while fetching the input 'gitlab:simple-nixos-mailserver/nixos-mailserver/nonexistent'
error: No commits returned by GitLab API -- does the ref really exist?
Change-Id: Id9bc79d98348500e152ed519bb3ac79a3d15c38d
This reverts commit 285bc67318.
Reason for revert: lix-project/lix#364
For some reason this broke `main` even though the change we are reverting passed CI! Mysterious, haunted, etc. Needs more debugging, let's turn it off for now.
Change-Id: Ica4819d61cd35b83eb52985bfcb657e858f025a9
If our shellHook is being run from a nested nix-shell (see 7a12bc200¹),
then (I think) it is run from a bash function due to the nesting, then
`return` is correct. If its `eval`'d though, then there isn't really a
correct way to early exit. So we can just unconditionally be executed in
a function.
Basically, we have IIFE at home.
[1]: 7a12bc2007
Change-Id: Iacad25cbbf66cde2911604e6061e56ad6212af7e
We reviewed this code a while ago, and we neglected to get a comment in
saying why it's Like This at the time. Let's fix that, since it is code
that looks very absurd at first glance.
Change-Id: Ib67b49605ef9ef1c84ecda1db16be74fc9105398
* changes:
util.hh: Delete remaining file and clean up headers
util.hh: Move nativeSystem to local-derivation-goal.cc
util.hh: Move stuff to types.hh
util.cc: Delete remaining file
util.{hh,cc}: Move ignoreException to error.{hh,cc}
util.{hh,cc}: Split out namespaces.{hh,cc}
util.{hh,cc}: Split out users.{hh,cc}
util.{hh,cc}: Split out strings.{hh,cc}
util.{hh,cc}: Split out unix-domain-socket.{hh,cc}
util.{hh,cc}: Split out child.{hh,cc}
util.{hh,cc}: Split out current-process.{hh,cc}
util.{hh,cc}: Split out processes.{hh,cc}
util.{hh,cc}: Split out file-descriptor.{hh,cc}
util.{hh,cc}: Split out file-system.{hh,cc}
util.{hh,cc}: Split out terminal.{hh,cc}
util.{hh,cc}: Split out environment-variables.{hh,cc}
Folding by default would prevent things like "Ctrl+F for nix-env" from
working trivially, but the user should be able to fold if they want to.
Change-Id: I5273272289f0f24e1f040c691580acfe33f66bd4
while refactoring the curl wrapper we inadvertently broken the immutable
flake protocol, because the immutable flake protocol accumulates headers
across the entire redirect chain instead of using only the headers given
in the final response of the chain. this is a problem because Some Known
Providers Of Flake Infrastructure set rel=immutable link headers only in
the penultimate entry of the redirect chain, and curl does not regard it
as worth returning to us via its response header enumeration mechanisms.
fixes lix-project/lix#358
Change-Id: I645c3932b465cde848bd6a3565925a1e3cbcdda0
Documents some of the weirdness of __curPos and the or keyword.
This does not fit well into any existing section for either of
them, though the use of or as a quasi-operator is mentioned in
the section on operators.
Addresses lix-project/lix#353
Change-Id: I7c906c8368843dca6944e8b22573b6d201cd9a76
grepQuietInvert is a typo introduced by c11836126b.
The test functional-timeout was failing silently because Bash considered
the command-not-found error as truthy.
Change-Id: Ic13829d02ec55d6ecd63a0f4d34ec0d32379609f
If a nested nix-shell is run inside a nix-shell, then the outer shell's
shellHook will be passed through and run again, unless the nested shell
defines its own.
With lix's hook, this can be annoying: forgetting to exit its nix-shell,
cd'ing to another repository & entering a nested nix-shell will happily
install lix's pre-commit hook in it.
This change makes lix's hook return early in such cases.
Change-Id: I91cb6eb6668f3a8eace36ecbdb01eb367861d77b
According to doc/manual/src/contributing/hacking.md, all development
shells should also be available in classic nix using the -A argument
to nix-shell, e.g.
nix-shell -A native-clangStdenvPackages
This was not actually the case; flake-compat generates attrsets like
nix-shell -A devShells.x86_64-linux.native-clangStdenvPackages
instead. These are unwieldy to use, so rather than changing the docs,
this changes the shell.nix file to result in the documented behavior.
Change-Id: I0920ccbdfddacf371f0aeaae7e290db65cf76ee7
check goals for timeouts first, and their activity fds only if no
timeout has occurred. checking for timeouts *after* activity sets
us up for assertion failures by running multiple build completion
notifiers, the first of which will kill/reap the the goal process
and consuming the Pid instance. when the second notifier attempts
to do the same it will core dump with an assertion failure in Pid
and take down not only the single goal, but the entire daemon and
all goals it was building. luckily this is rare in practice since
it requires a build to both finish and time out at the same time.
writing a test for this is not feasible due to how much it relies
on scheduling to actually trigger the underlying bug, but on idle
machines it can usually be triggered by running multiple sleeping
builds with timeout set to the sleep duration and `--keep-going`:
nix-build --timeout 10 --builders '' --keep-going -E '
with import <nixpkgs> {};
builtins.genList
(i: runCommand "foo-${toString i}" {} "sleep 10")
100
'
Change-Id: I394d36b2e5ffb909cf8a19977d569bbdb71cb67b