Re: Question regarding 'Conditional jump or move depends on uninitialised value(s)'
John Reiser <[email protected]> Sun, 16 Jun 2024 13:03:56 -0700
| Newsgroups | gmane.comp.debugging.valgrind |
|---|---|
| Message-ID | <[email protected]> |
> What happens is that a rather large class is allocated via operator new > which comes with tons of subsequent data. Unfortunately, a lot of that > data isn't default initialized so it's rather impossible to go by trial > and error. Valgrind does report the place where the condition is but > it's a super busy loop that works on tons of templated data. The "ultimate hammer" or "magic wand" is 'rr', which is "Record and Replay". By using it you can execute *backwards*, that is "back up" from the point of error to as far back as you want, examining memory as you go; or even setting breakpoints or watchpoints to see when (in the past!) state changed. See https://rr-project.org ; also search the 'net for "rr record replay". You'll have to learn this new style of debugging, and you will need a lot of disk space: 100GB is typical. But you *will* find the bug!