https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109163
Bug ID: 109163
Summary: SARIF (and other JSON) output files are
non-deterministic
Product: gcc
Version: 13.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: other
Assignee: unassigned at gcc dot gnu.org
Reporter: dmalcolm at gcc dot gnu.org
Target Milestone: ---
gcc/json.cc's json::object uses a hash_map for tracking the key/value pairs,
and object::print iterates through them in arbitrary order, so every time we
emit json files they can potentially vary, which makes it much harder to
compare them from run to run (see e.g. PR 105959).
It would probably be much more user-friendly to use an ordered_hash_map here to
preserve insertion order and thus have deterministic output. I don't know if
this would have a noticeable performance hit.
