Bech32 support was only added to CpuMiner in January, 2019 in 7e8960212f0055d6dafaa3c80812c50cec291de3.
v2.5.0 is a release form 2017, and looks to be the latest precompiled release.
You will need to mine to a p2sh or p2pkh address, or compile a newer version yourself.
In any case, CPU mining bitcoin is a waste of time, you will never see any ROI ...
For development it's often helpful to start both nodes in regression test mode (regtest mode). The developer has his own private blockchain and can choose when to create a new block. You can use bitcoin-cli -regtest generate 1 to generate a new block.
For more information see Developer Examples - Regtest Mode.
These games do not actually generate any Bitcoin. No Bitcoin is being mined in these games; that's not how Bitcoin works.
The Bitcoin comes from the service running the game. They are doing something other than running the game that is earning them Bitcoin. They then use that Bitcoin to give small amounts to their users. The Bitcoin is typically earned ...
I can confirm your code works. I implented your code into a few projects that, in turn, forked from PIVX.
I wasn't able to generate genesis blocks in every project - which would suggest there is a bit more to this then just chainparams.cpp. However I was succesful in having the daemon produce genesis blocks that were also usable in some of these projects ...
-t 6 threads should be the best setting, half of the L3 cache. Give it a try and let us know how it goes. Also, see what the developer of xmrig (cpuminer 'competitor') says about it:
xmrig commented on Aug 29, 2017
"...Also 6 threads per CPU/Node is optimal, because of 12 MB L3 cache, each thread required 2 MB cache for optimal performance, more threads ...
minerd -a scrypt --threads=1 -o stratum+tcp://us.litecoinpool.org:3333 -O ab1jx.4:4
From a script and it works fine. ab1jx is my username on litecoinpool, worker is 4, password is 4. Only 1 thread to make it sort of a background process, leave that out to run at full throttle.
I don't get accepted lines often either with cpuminer, I assume ...
Q: What happened to CPU and GPU mining?
A: Their efficiency makes them irrelevant in the bitcoin mining world today
and the author has no interest in supporting alternative coins that are better
mined by these devices
The E7-4830v3 has 10 physical cores and 20MB of L3 cache. With two CPUs, you'd only have 20 physical cores and 40MB of L3. Since every thread is doing exactly the same thing, hyper-threading is virtually useless. It wouldn't help you anyway since you only have 2MiB per physical core and that's exactly what cryptonight requires.
So, short answer, with 40MB ...