I have two machines with Rx570s in them, both 4GB.

One is Windows.. One is Linux.

The Linux version crashes with this error, but ONLY if export GPU_FORCE_64BIT_PTR=0..
if I set it to export GPU_FORCE_64BIT_PTR=1, it works fine..?

Is this possibly a driver issue? Ubuntu 18.04.3, repo cl drivers

error:
$ ./start.sh

����������������������������������������������������������������ͻ
�                Claymore's Dual GPU Miner - v15.0               �
�              ETH + DCR/SIA/LBC/PASC/BLAKE2S/KECCAK             �
����������������������������������������������������������������ͼ

ETH: 1 pool is specified
Main Ethereum pool is daggerhashimoto.usa-new.nicehash.com:3353
DCR: 0 pool is specified
At least 16 GB of Virtual Memory is required for multi-GPU systems
Make sure you defined GPU_MAX_ALLOC_PERCENT 100
Be careful with overclocking, use default clocks for first tests
Press "s" for current statistics, "0".."9" to turn on/off cards, "r" to reload pools, "e" or "d" to select current pool, "x" to select GPU, "z" to find best -dcri values
OpenCL initializing...

AMD Cards available: 1
GPU #0: Ellesmere (Radeon RX 570 Series), 3072 MB available, 32 compute units (pci bus 8:0:0)
GPU #0 recognized as Radeon RX 470/570
POOL/SOLO version
AMD ADL library not found.
Cannot build OpenCL program for GPU 0
./start.sh: line 9: 13998 Segmentation fault      (core dumped) ./ethdcrminer64 -asm 1 -dcri 8 -epool stratum+tcp://XX -eworker XX -ewal XX -epsw x -esm 3 -allpools 1 -estale 0