Not necessarily. A decent percentage of the time someone is experiencing a "heisenbug" it's because there are some stale object files sitting around, and the b

Not necessarily. A decent percentage of the time someone is experiencing a "heisenbug" it's because there are some stale object files sitting around, and the build state has gotten inconsistent (makefile bugs, bad tracking of dependencies, or what have you). You go to build debug, everything works, you shrug, make clean, remake, and then you're golden again. Obviously that's really not the way to go, though, because you risk mistaking an uncommon crash for "just had to rebuild, I guess" - but if you're comfortable reading assembly or what-have-you, you can usually confirm the "stale object files" thing easily - and then fix your build ;)