What compilers are people using for FPGAs? It seems all the compilers are proprietary, and not much fun to use on Linux.
There has been significant progress in reverse engineering bitstream formats of some FPGAs which has allowed the development of open source FPGA workflows. If you want to know more, take a look at:
Icestorm http://www.clifford.at/icestorm/
Yosys http://www.clifford.at/yosys/
NextPNR https://github.com/YosysHQ/nextpnr
SymbiFlow https://symbiflow.github.io/