Since this is a top hit on google for this issue, I'm posting here just to add that you see this error if you add a println() to your finalize function, to check whether it is called :o)
One solution is to increment a global counter in the finalizer and print the counter before and after gc(). Andrew On Sunday, 8 February 2015 16:15:18 UTC-3, Rémi Berson wrote: > > Hi guys, > > While creating a tiny wrapper over the C/C++ primesieve > <https://github.com/kimwalisch/primesieve> library, I encountered an > error while trying to finalize the Ptr returned by a function. This pointer > must be freed by another function from the library, so I tried to wrap it > into a finalizer function but it doesn't work because of the following > error: "task switch not allowed from inside gc finalizer". Could someone > explain how this could be done properly? I would try to avoid the returned > array if possible. Here is the code so far: > > > const LIB_PRIMESIEVE = "libprimesieve.so" > > type C_primesieve_array > handle::Ptr{Int32} > end > > function primes(n::Int) > size = Cint[0] > primes_ptr = ccall( > (:primesieve_generate_primes, LIB_PRIMESIEVE), > C_primesieve_array, > (UInt64, UInt64, Ptr{Cint}, Int), > 1, n, size, 3) > > function primesieve_array_finalizer(primesieve_arr::C_primesieve_array > ) > ccall( > (:primesieve_free, LIB_PRIMESIEVE), > Void, (Ptr{Int32},), primesieve_arr.handle) > end > > finalizer(primes_ptr, primesieve_array_finalizer) > return pointer_to_array(primes_ptr.handle, size[1], false) > end > > > Thank you very much, > Rémi > >
