Deterministic package files break lldb #9512
Description
Problem
#8864 introduced deterministic packaging. One of the key aspects is that the mtime of every file is set to 0. Unfortunately, this seems to prevent lldb from reading the file. This means that stepping into dependencies from crates.io won't show any source information.
Arguably this is a bug in lldb. This does not seem to affect gdb. Unfortunately I feel like the likelyhood of fixing this in lldb is low (and even if it does get fixed, I imagine it would take years to trickle into Apple's release).
Steps
cargo new foo
cd foo
cargo package --allow-dirty
tar -xzvf target/package/foo-0.1.0.crate
cd foo-0.1.0
ls -al src # verify that timestamp is Dec 31 1969 main.rs
cargo build
lldb target/debug/foo
b main.rs:2
run
######
# You should see output like this, notice there is no source information.
# Process 176294 launched: '/home/eric/Temp/foo/foo-0.1.0/target/debug/foo' (x86_64)
# Process 176294 stopped
# * thread #1, name = 'foo', stop reason = breakpoint 1.1
# frame #0: 0x000055555555b9d4 foo`foo::main::h2ffdc3ce2a8b2165 at main.rs:2:5
quit
touch src/main.rs
cargo build
lldb target/debug/foo
b main.rs:2
run
######
# You should see output like this, notice we now have source!
# Process 176406 launched: '/home/eric/Temp/foo/foo-0.1.0/target/debug/foo' (x86_64)
# Process 176406 stopped
# * thread #1, name = 'foo', stop reason = breakpoint 1.1
# frame #0: 0x000055555555b9d4 foo`foo::main::h2ffdc3ce2a8b2165 at main.rs:2:5
# 1 fn main() {
# -> 2 println!("Hello, world!");
# 3 }Possible Solution(s)
I'm not sure. Cargo could set the timestamp of files when they are extracted. Would just need to be careful with #7590. I think setting all files to the same timestamp should be sufficient?
Notes
Output of cargo version: cargo 1.54.0-nightly (070e459 2021-05-11)
Seems to affect lldb on both macOS and Linux.
Linux: lldb version 10.0.0 and lldb version 11.0.0 and lldb version 12.0.1
macOS: lldb-1200.0.44.2 (Xcode 12.4 (12D4e))