On Thursday, 10 July 2014 at 15:36:53 UTC, francesco cattoglio
wrote:
A code I'm working on stops working and starts printing an
infinite loop of
core.exception.InvalidMemoryOperationError
to the command line output. The code is quite complex and the
bug seems to present itself almost in random situation so I
would like to try to understand the issue better before looking
for the wrong line of code hiding somewhere. I've read it might
be that something is trying to allocate during a destructor
call, but it sounds really strange to me that there's a
neverending amount of exceptions being thrown. This is the
first exception being thrown (nothing is thrown before the
infinite loop begins).
Anyone has suggestions/ideas/heard of a similar stuff before?
If you look at the source for the garbage collector, the only
place that error is called is if the gc is trying to malloc or
execute other memory operations while the collector is running.
I ran across this myself because an assert was getting triggered
in a destructor. Since an assert tries to malloc and the
destructor is called by the GC, I got an
InvalidMemoryOperationError which swallowed up the message from
the original assert.
By putting printfs in the code path in druntime, I was able to
track it down to that destructor, otherwise I had no idea where
the invalid memory error was getting triggered. You can probably
do the same, but you can be sure it's a GC issue, and I would
guess tied to allocating in a destructor (unless you happen to be
calling InvalidMemoryOperationErrors somewhere in your own code
or some library that you're using, which is unlikely).
