[PATCH] D105169: [Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default

[Juneyoung Lee via Phabricator via cfe-commits]

aqjune added a comment.

It seems the original code has a use of an uninitialized variable.
Line 4420 at seek-preproc.c (function `ff_seek_frame_binary`):

   int64_t pos_min=pos_min, pos_max=pos_max, pos, pos_limit; // pos_min and pos_max are self-assigned.
  ...
  if (sti->index_entries) {
     ...
  }
  // pos_min and pos_max are used as arguments below
  pos = ff_gen_search(s, stream_index, target_ts, pos_min, pos_max, pos_limit,
                       ts_min, ts_max, flags, &ts, avif->read_timestamp);

https://gist.github.com/aqjune/3bd0ea19bbc12b4744843c0c070e994c

If the branch is not taken, `pos_min` and `pos_max` are read while they are still uninitialized.

I guess the variables are self-assigned to avoid warnings?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D105169/new/

https://reviews.llvm.org/D105169