Here is a public report from the TRACTOR evaluation team: https://github.com/DARPA-TRACTOR-Program/Reports/blob/main/F...
There are also some papers being published that were funded by TRACTOR, such as https://homes.cs.washington.edu/~mernst/pubs/c-rust-macros-p...
Evaluations of six translators. That's real progress.
Here are the test cases for evaluation #1.[1] There's good coverage of the C language, but the individual tests are mostly simple exercises of one C feature. The next round of test cases will probably be closer to useful programs.
[1] https://github.com/DARPA-TRACTOR-Program/PUBLIC-Test-Corpus