Bug#905598: llvm-bcanalyzer diffs its own tempfile names

[Christoph Berg]

Package: diffoscope
Version: 99
Severity: normal

Hi,

just when postgresql-10 was almost reproducible (and I hope to really
weed the remaining `uname -m` bits in the upload on Thursday),
postgresql-11 came around which adds JIT for SQL queries via LLVM. For
this, LLVM bytecode (.bc) files are stored which are then compiled at
runtime.

Looking at
https://tests.reproducible-builds.org/debian/rb-pkg/experimental/amd64/postgresql-11.html
I noticed that the diff of the .bc files (which differ because they
store the build paths), there's a bit there the `llvm-bcanalyzer -dump`
output itself introduces a path, which is then reported as difference:

Summary of /srv/reproducible-results/rbuild-debian/tmp.Xss3ZdRPQz/dbd-tmp-3DqxLmN/diffoscope_wmjtu2i8/tmpdktglxs6/0/8.bc:
Summary of /srv/reproducible-results/rbuild-debian/tmp.Xss3ZdRPQz/dbd-tmp-3DqxLmN/diffoscope_wmjtu2i8/tmpwintfm2m/0/8.bc:

Christoph