These stack traces kind of suck for the reasons mentioned on the
CppTrace page here (no symbols for inline functions is a major one):
https://github.com/jeremy-rifkin/cpptrace
I would consider using CppTrace if it were packaged, but to be honest, I
think that the more reasonable option is actually to move entirely to
out-of-process crash handling and symbolization.
The reason for this is that if you want to generate anything of
substance on SIGSEGV or really any deadly signal, you are stuck in
async-signal-safe land, which is not a place to be trying to run a
symbolizer. LLVM does it anyway, probably carefully, and chromium *can*
do it on debug builds but in general uses crashpad:
https://source.chromium.org/chromium/chromium/src/+/main:base/debug/stack_trace_posix.cc;l=974;drc=82dff63dbf9db05e9274e11d9128af7b9f51ceaa;bpv=1;bpt=1
However, some stack traces are better than *no* stack traces when we get
mystery exceptions falling out the bottom of the program. I've also
promoted the path for "mystery exceptions falling out the bottom of the
program" to hard crash and generate a core dump because although there's
been some months since the last one of these, these are nonetheless
always *atrociously* diagnosed.
We can't improve the crash handling further until either we use Crashpad
(which involves more C++ deps, no thanks) or we put in the ostensibly
work in progress Rust minidump infrastructure, in which case we need to
finish full support for Rust in libutil first.
Sample report:
Lix crashed. This is a bug. We would appreciate if you report it at https://git.lix.systems/lix-project/lix/issues with the following information included:
Exception: std::runtime_error: lol
Stack trace:
0# nix::printStackTrace() in /home/jade/lix/lix3/build/src/nix/../libutil/liblixutil.so
1# 0x000073C9862331F2 in /home/jade/lix/lix3/build/src/nix/../libmain/liblixmain.so
2# 0x000073C985F2E21A in /nix/store/p44qan69linp3ii0xrviypsw2j4qdcp2-gcc-13.2.0-lib/lib/libstdc++.so.6
3# 0x000073C985F2E285 in /nix/store/p44qan69linp3ii0xrviypsw2j4qdcp2-gcc-13.2.0-lib/lib/libstdc++.so.6
4# nix::handleExceptions(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::function<void ()>) in /home/jade/lix/lix3/build/src/nix/../libmain/liblixmain.so
5# 0x00005CF65B6B048B in /home/jade/lix/lix3/build/src/nix/nix
6# 0x000073C985C8810E in /nix/store/dbcw19dshdwnxdv5q2g6wldj6syyvq7l-glibc-2.39-52/lib/libc.so.6
7# __libc_start_main in /nix/store/dbcw19dshdwnxdv5q2g6wldj6syyvq7l-glibc-2.39-52/lib/libc.so.6
8# 0x00005CF65B610335 in /home/jade/lix/lix3/build/src/nix/nix
Change-Id: I1a9f6d349b617fd7145a37159b78ecb9382cb4e9
When generating shell completions, no logging output should be visible because
it would destroy the shell prompt. Originally this was attempted to be done by
simply disabling the progress bar (ca946860ce),
since the situation is particularly bad there (the screen clearing required for
the rendering ends up erasing the shell prompt). Due to overlooking the
implementation of this hack, it was accidentally undone during a later change
(0dd1d8ca1c).
Since even with the hack correctly in place, it is still possible to mess up
the prompt by logging output (for example warnings for disabled experimental
features, or messages generated by `builtins.trace`), simply send it to the bit
bucket where it belongs. This was already done for bash and zsh
(9d840758a8), and it seems that fish was simply
missed at that time. The last trace of the no-longer-working and obsolete hack
is deleted too.
Fixes: #513
Change-Id: I59f1ebf90903034e2059298fa8d76bf970bc3315
When the multi-line log format is enabled, the progress bar usually occupies
multiple lines on the screen. When stopping the progress bar, only the last
line was wiped, leaving all others visible on the screen. Erase all lines
belonging to the progress bar to prevent these leftovers.
Asking the user for input is theoretically affected by a similar issue, but
this is not observed in practice since the only place where the user is asked
(whether configuration options coming from flakes should be accepted) does not
actually have multiple lines on the progress bar. However, there is no real
reason to not fix this either, so let's do it anyway.
Change-Id: Iaa5a701874fca32e6f06d85912835d86b8fa7a16
This will stop printing stuff to dumb terminals that they don't support.
I've overall audited usage of isatty and replaced the ones with intent
to mean "is a Real terminal" with checking for that. I've also caught a
case of carelessly assuming "is a tty" means "should be colour" in
nix-env.
Change-Id: I6d83725d9a2d932ac94ff2294f92c0a1100d23c9
This:
- Converts a bunch of C style casts into C++ casts.
- Removes some very silly pointer subtraction code (which is no more or
less busted on i686 than it began)
- Fixes some "technically UB" that never had to be UB in the first
place.
- Makes finally follow the noexcept status of the inner function. Maybe
in the future we should ban the function from not being noexcept, but
that is not today.
- Makes various locally-used exceptions inherit from std::exception.
Change-Id: I22e66972602604989b5e494fd940b93e0e6e9297
SimpleLogger is not fully thread-safe, and all loggers that wrap it are
also not safe accordingly. this does not affect much, but in rare cases
it can cause interleaving of messages on stderr when used with the json
or raw log formats. the fix applied here is a bit of a hack, but fixing
this properly requires rearchitecting the logger infrastructure. nested
loggers are not the most natural abstraction here, and it is biting us.
Change-Id: Ifbf34fe1e85c60e73b59faee50e7411c7b5e7c12
it's only used once, and even that one use is highly questionable. more
instances of warnOnce should be much more principled than this has been
Change-Id: I5856570c99cb44462e700d753d0c706a5db03c4b
Activities can set display attributes in their log output using the "Select
Graphics Rendition" functionality. To prevent interfering with subsequent text
displayed, these should be reset after writing the log line. The multiline
progress bar neglected to do this, resulting for example in a colorised
"building …" header in the next line. Reset the attributes properly, like the
standard progress bar already does.
Change-Id: I1dc69f4a1d747a76b83e8721a72d9bb0e5554488
not printing activities at all when no progress information is available
hides *all* progress information from e.g. flake show. this is not ideal
and needs to be fixed, but the fix *still* has problems with flake show:
in multiline mode we will overwrite all useful flake show output as soon
as the progress bar is redrawn. flake show output is also mangled in any
number of other situations (like -v being set), so we should probably be
not too worried about it and fix progress reporting properly another day
Change-Id: I6d39d670e261bbae00560b6a8e15dec8e16b35c4
Previously, the progress bar had two subtly different states in which the bar
would not actually render, both with their own shortcomings: inactive (which
was irreversible) and paused (reversible, but swallowing logs). Furthermore,
there was no way of resetting the statistics, so a very bad solution was
implemented (243c0f18da) that would create a new
logger for each line of the repl, leaking the previous one and discarding the
value of printBuildLogs. Finally, if stderr was not attached to a TTY, the
update thread was started even though the logger was not active, violating the
invariant required by the destructor (which is not observed because the logger
is leaked).
In this commit, the two aforementioned states are unified into a single one,
which can be exited again, correctly upholds the invariant that the update
thread is only running while the progress bar is active, and does not swallow
logs. The latter change in behavior is not expected to be a problems in the
rare cases where the paused state was used before, since other loggers (like
the simple one) don't exhibit it anyway. The startProgressBar/stopProgressBar
API is removed due to being a footgun, and a new method for properly resetting
the progress is added.
Co-Authored-By: Qyriad <qyriad@qyriad.me>
Change-Id: I2b7c3eb17d439cd0c16f7b896cfb61239ac7ff3a
this most notably affects `nix eval`: if there is no progress bar to be
shown and no activities going on we should not print anything at all. a
progress bar with no activities would print a bunch of terminal escapes
*and a space*, which is not helpful in simple cases like nix eval -E 1.
notably this does *not* affect nix eval called on non-terminal outputs,
but it is slightly confusing nevertheless (and not difficult to avoid).
fixes #424
Change-Id: Iee793c79ba5a485d6606e0d292ed2eae6dfb7216
This is primarily for readability, but iwrc chaining std::string's
operator+ is also pretty scuffed performance-wise, and this was doing a
lot of operator+ chainging.
Change-Id: I9f25235df153eb2bbb491f1ff7ebbeed9a8ec985
copy-constructing or assigning from pid_t can easily lead to duplicate
Pid instances for the same process if a pid_t was used carelessly, and
Pid itself was copy-constructible. both could cause surprising results
such as killing processes twice (which could become very problemantic,
but luckily modern systems don't reuse PIDs all that quickly), or more
than one piece of the code believing it owns a process when neither do
Change-Id: Ifea7445f84200b34c1a1d0acc2cdffe0f01e20c6
Add the log-formats `multiline` and `multiline-with-logs` which offer
multiple current active building status lines.
Change-Id: Idd8afe62f8591b5d8b70e258c5cefa09be4cab03
This was generating an out-of-range verbosity value. We should just
process it as an int and then convert to verbosity with a clamping
function, which trivially avoids any domain type violations.
Change-Id: I0ed20da8e1496a1225ff3008b76827d99265d404
They are enabled by default, and Meson will also prints whether or not
they're enabled at the bottom at the end of configuration.
Change-Id: I48db238510bf9e74340b86f243f4bbe360794281
Here's my guide so far:
$ rg '((?!(recursive).*) Nix
(?!(daemon|store|expression|Rocks!|Packages|language|derivation|archive|account|user|sandbox|flake).*))'
-g '!doc/' --pcre2
All items from this query have been tackled. For the documentation side:
that's for #162.
Additionally, all remaining references to github.com/NixOS/nix which
were not relevant were also replaced.
Fixes: #148.
Fixes: #162.
Change-Id: Ib3451fae5cb8ab8cd9ac9e4e4551284ee6794545
Signed-off-by: Raito Bezarius <raito@lix.systems>
It seems like someone implemented precompiled headers a long time ago
and then it never got ported to meson or maybe didn't work at all.
This is, however, blessedly easy to simply implement. I went looking for
`#define` that could affect the result of precompiling the headers, and
as far as I can tell we aren't doing any of that, so this should truly
just be free build time savings.
Previous state:
Compilation (551 times):
Parsing (frontend): 1302.1 s
Codegen & opts (backend): 956.3 s
New state:
**** Time summary:
Compilation (567 times):
Parsing (frontend): 1123.0 s
Codegen & opts (backend): 1078.1 s
I wonder if the "regression" in codegen time is just doing the PCH
operation a few times, because meson does it per-target.
Change-Id: I664366b8069bab4851308b3a7571bea97ac64022
This breaks downstreams linking to us on purpose to make sure that if
someone is linking to Lix they're doing it on purpose and crucially not
mixing up Nix and Lix versions in compatibility code.
We still need to fix the internal includes to follow the same schema so
we can drop the single-level include system entirely. However, this
requires a little more effort.
This adds pkg-config for libfetchers and config.h.
Migration path:
expr.hh -> lix/libexpr/expr.hh
nix/config.h -> lix/config.h
To apply this migration automatically, remove all `<nix/>` from
includes, so: `#include <nix/expr.hh>` -> `#include <expr.hh>`. Then,
the correct paths will be resolved from the tangled mess, and the
clang-tidy automated fix will work.
Then run the following for out of tree projects:
```
lix_root=$HOME/lix
(cd $lix_root/clang-tidy && nix develop -c 'meson setup build && ninja -C build')
run-clang-tidy -checks='-*,lix-fixincludes' -load=$lix_root/clang-tidy/build/liblix-clang-tidy.so -p build/ -fix src
```
Related: lix-project/nix-eval-jobs#5
Fixes: #279
Change-Id: I7498e903afa6850a731ef8ce77a70da6b2b46966
The interrupt-blocking code was originally introduced 20 years ago so that
trying to log an error message does not result in an interrupt exception being
thrown and then going unhandled (c8d3882cdc).
However, the logging code does not check for interrupts any more
(054be50257), so this reasoning is no longer
applicable. Delete this code so that later interrupts are unblocked again, for
example in the next line entered into the repl.
Closes: #296
Change-Id: I48253f5f4272e75001148c13046e709ef5427fbd
As I complained in
https://github.com/NixOS/nix/pull/6784#issuecomment-1421777030 (a
comment on the wrong PR, sorry again!), #6693 introduced a second
completions mechanism to fix a bug. Having two completion mechanisms
isn't so nice.
As @thufschmitt also pointed out, it was a bummer to go from `FlakeRef`
to `std::string` when collecting flake refs. Now it is `FlakeRefs`
again.
The underlying issue that sought to work around was that completion of
arguments not at the end can still benefit from the information from
latter arguments.
To fix this better, we rip out that change and simply defer all
completion processing until after all the (regular, already-complete)
arguments have been passed.
In addition, I noticed the original completion logic used some global
variables. I do not like global variables, because even if they save
lines of code, they also obfuscate the architecture of the code.
I got rid of them moved them to a new `RootArgs` class, which now has
`parseCmdline` instead of `Args`. The idea is that we have many argument
parsers from subcommands and what-not, but only one root args that owns
the other per actual parsing invocation. The state that was global is
now part of the root args instead.
This did, admittedly, add a bunch of new code. And I do feel bad about
that. So I went and added a lot of API docs to try to at least make the
current state of things clear to the next person.
--
This is needed for RFC 134 (tracking issue #7868). It was very hard to
modularize `Installable` parsing when there were two completion
arguments. I wouldn't go as far as to say it is *easy* now, but at least
it is less hard (and the completions test finally passed).
Co-authored-by: Valentin Gagarin <valentin.gagarin@tweag.io>
Change-Id: If18cd5be78da4a70635e3fdcac6326dbfeea71a5
(cherry picked from commit 67eb37c1d0de28160cd25376e51d1ec1b1c8305b)
This commit adds several meson.build, which successfully build and
install Lix executables, libraries, and headers. Meson does not yet
build docs, Perl bindings, or run tests, which will be added in
following commits. As such, this commit does not remove the existing
build system, or make it the default, and also as such, this commit has
several FIXMEs and TODOs as notes for what should be done before the
existing autoconf + make buildsystem can be removed and Meson made the
default. This commit does not modify any source files.
A Meson-enabled build is also added as a Hydra job, and to
`nix flake check`.
Change-Id: I667c8685b13b7bab91e281053f807a11616ae3d4
These now have equivalents in the standard lib in C++20. This change was
performed with a custom clang-tidy check which I will submit later.
Executed like so:
ninja -C build && run-clang-tidy -checks='-*,nix-*' -load=build/libnix-clang-tidy.so -p .. -fix ../tests | tee -a clang-tidy-result
Change-Id: I62679e315ff9e7ce72a40b91b79c3e9fc01b27e9
While preparing PRs like #9753, I've had to change error messages in
dozens of code paths. It would be nice if instead of
EvalError("expected 'boolean' but found '%1%'", showType(v))
we could write
TypeError(v, "boolean")
or similar. Then, changing the error message could be a mechanical
refactor with the compiler pointing out places the constructor needs to
be changed, rather than the error-prone process of grepping through the
codebase. Structured errors would also help prevent the "same" error
from having multiple slightly different messages, and could be a first
step towards error codes / an error index.
This PR reworks the exception infrastructure in `libexpr` to
support exception types with different constructor signatures than
`BaseError`. Actually refactoring the exceptions to use structured data
will come in a future PR (this one is big enough already, as it has to
touch every exception in `libexpr`).
The core design is in `eval-error.hh`. Generally, errors like this:
state.error("'%s' is not a string", getAttrPathStr())
.debugThrow<TypeError>()
are transformed like this:
state.error<TypeError>("'%s' is not a string", getAttrPathStr())
.debugThrow()
The type annotation has moved from `ErrorBuilder::debugThrow` to
`EvalState::error`.
(cherry picked from commit c6a89c1a1659b31694c0fbcd21d78a6dd521c732)
Change-Id: Iced91ba4e00ca9e801518071fb43798936cbd05a
jade
alois31
eldritch horrors
Qyriad
kloenk
raito
Tom Hubrecht
