segfault on Gentoo

[dm9pZCAq]

Describe the bug
segfault when running gitui

To Reproduce
Steps to reproduce the behavior:
run gitui on eny directory

Context (please complete the following information):

• OS/Distro + Version: Gentoo on musl libc
• GitUI Version 0.17.1
• Rust version: 1.54.0
• system libgit2 version: 1.2.0 with remote: Mark git_remote_name_is_valid as GIT_EXTERN libgit2/libgit2#6032 applied
• system openssl version: 1.1.1l
• musl version: 1.2.2

Additional context
with gitui-0.16.2 everything works fine, but with same ebuild but for 0.17.1 after successful build, it's segfaults at runtime

firstly i was think this is because of git_branch name is_valid but my tests compiles and runs fine

C

#include <stdio.h>
#include <git2/branch.h>

#define LEN(X) (sizeof(X) / sizeof *(X))

int
main(void)
{

	size_t	    i;
	int	    status  = -1;
	const char *tests[] = {
		"refs/heads/name",
		"master",
		"-master",
	};

	for (i = 0; i < LEN(tests); i -= (~0L), status = -1) {
		printf("git_branch_name_is_valid(%s) -> %d, ",
		       tests[i],
		       git_branch_name_is_valid(&status, tests[i]));
		printf("status %d\n", status);
	}

	return 0;
}

out:

git_branch_name_is_valid(refs/heads/name) -> -1, status 0
git_branch_name_is_valid(master) -> -1, status 0
git_branch_name_is_valid(-master) -> 0, status 0

lddtree:

a.out => ./a.out (interpreter => /lib/ld-musl-x86_64.so.1)
    libgit2.so.1.2 => /usr/lib/libgit2.so.1.2
        libssl.so.1.1 => /usr/lib/libssl.so.1.1
        libcrypto.so.1.1 => /usr/lib/libcrypto.so.1.1
        libpcre.so.1 => /lib/libpcre.so.1
        libhttp_parser.so.2.9 => /usr/lib/libhttp_parser.so.2.9
        libz.so.1 => /lib/libz.so.1
        libssh2.so.1 => /usr/lib/libssh2.so.1
    libc.so => /usr/lib/libc.so

rust

use git2::Branch;

type BoxedErr = Box<dyn(::std::error::Error)>;
type Result<T> = ::std::result::Result<T, BoxedErr>;

fn main() -> Result<()> {
    for name in ["refs/heads/name", "master", "-master"] {
        let valid = Branch::name_is_valid(name)?;
        println!("{:#?}", valid);
    }

    Ok(())
}

out:

true
true
false

lddtree:

Test => ./target/debug/Test (interpreter => /lib/ld-musl-x86_64.so.1)
    libgit2.so.1.2 => /usr/lib/libgit2.so.1.2
        libpcre.so.1 => /lib/libpcre.so.1
        libhttp_parser.so.2.9 => /usr/lib/libhttp_parser.so.2.9
        libz.so.1 => /lib/libz.so.1
        libssh2.so.1 => /usr/lib/libssh2.so.1
    libssl.so.1.1 => /usr/lib/libssl.so.1.1
    libcrypto.so.1.1 => /usr/lib/libcrypto.so.1.1
    libgcc_s.so.1 => /usr/lib/gcc/x86_64-gentoo-linux-musl/11.2.0/libgcc_s.so.1
    libc.so => /usr/lib/libc.so

strace gitui

maybe you know what it could be?

[extrawurst]

I am clearly not enough of a linux pro for this. on my ubuntu box for dummies everything seems to works. did you try with the stock libgit2 1.2.0?

also can you run it in a debugger so we get a useful callstack where it crashes?

@dm9pZCAq also I am curious: what added value the issue description "yet another" had?

[dm9pZCAq]

also can you run it in a debugger so we get a useful callstack where it crashes?

can you recommend some useful tools for rust debugging?

what added value the issue description "yet another" had?

because that's "yet another" weird segfault on Gentoo (first is here #459)

[dm9pZCAq]

ok, with best debug tool (putting dbg! after each line in fn main) i find out that segfault caused by this line

gitui/src/main.rs

Line 105 in 7dd6b4e

asyncgit::register_tracing_logging();

after i commented it out, everything works fine

[dm9pZCAq]

for me, this causes segfault too

#include <stdio.h>
#include <git2/trace.h>

void
callback(git_trace_level_t level, const char *msg)
{
	puts(msg);
}

int
main(void)
{
	printf("%d\n", git_trace_set(GIT_TRACE_TRACE, callback));
	return 0;
}

i'll go figure it out...

[dm9pZCAq]

ok, i figured out...

the problem was that i compiled libgit2 without tracing support (-DENABLE_TRACE=OFF)

gitui is only package on my system, that requires tracing from libgit

maybe it would be better to add --feature for libgit tracing, and users that don't need it, will be able to disable it?

[extrawurst]

ok, i figured out...

the problem was that i compiled libgit2 without tracing support (-DENABLE_TRACE=OFF)

gitui is only package on my system, that requires tracing from libgit

maybe it would be better to add --feature for libgit tracing, and users that don't need it, will be able to disable it?

afaik tracing is on by default. so yeah maybe a note in the readme to mention that we require this to be enabled would make sense

[dm9pZCAq]

tracing is on by default

on most distros yes, but on Gentoo you have choice what to use and this is not enabled by default

[dm9pZCAq]

this is how i did it:

• dependencies
• sed sources

---

it can be enabled by default, but have this choice will be cool

?

asyncgit/src/lib.rs:

///
#[cfg(feature = "trace-libgit")]
pub fn register_tracing_logging() -> bool {
    fn git_trace(level: git2::TraceLevel, msg: &str) {
        log::info!("[{:?}]: {}", level, msg);
    }
    git2::trace_set(git2::TraceLevel::Trace, git_trace)
}

///
#[cfg(not(feature = "trace-libgit"))]
pub fn register_tracing_logging() -> bool {
    true
}

and add feature to Cargo.toml

[extrawurst]

@dm9pZCAq I gladly accept a PR for this 👍