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
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
jade
alois31
Qyriad