hangs in v0.3.0

[matthiaskrgr]

since the update to v0.3.0, I noticed that treereduce-rust would often start reducing but then just hang in the middle and no longer make any progress.

treereduce-rust  --passes=10  --min-reduction=10 --interesting-exit-code=101 --stats --source  /home/matthias/vcs/github/RUST_CODE/ALL_TESTS/icemaker/04FCCD075E8AFA9FB081E547DEE5329C2F2F0AF68FD1649DF975149BE0F1E10D.rs  -- ~/.rustup/toolchains/local-debug-assertions/bin/rustc   @@.rs
[INFO] Starting pass 1 / 10
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Downgrading to 0.2.2 fixed this for me :/

treereduce_hang.rs.zip

[langston-barrett]

@matthiaskrgr Thanks for the report, will look into this!

[vext01]

I've encountered the same.

I notice that it terminates fine with -j 1, so I assume it's to do with threading, maybe a deadlock.

[j2kun]

I also hit this, with the following repro:

#include <stdio.h>

int main() {
  char * hello = "hello, world!" + 3;
  char * charstring = 'h' + "ello, world!";

  printf("hello=%s, charstring=%s.\n", hello, charstring);
  return 0;
}

test:

#!/bin/bash

set -eoux pipefail

cat <&0 > tmp.c
clang -s tmp.c -o tmp
./tmp | grep -q "=lo, world"

Command:

treereduce-c --fast -s test.c test.sh

Adding -j 1 causes it to finish in 2s, otherwise it hangs for over 30 minutes (at which point I killed the process).

[langston-barrett]

Thank you all very much for the reports and for your interest in the project! This looks like a very silly mistake on my part. I have a candidate fix in #221 that fixes @j2kun's test-case for me, though I'm also seeing a debug assertion failing that I'd like to investigate.

[langston-barrett]

I've published v0.3.1 with both fixes. Thanks again y'all!