When using Intel® FPGA OpenCL™ SDK 18.1, customer may get error information as "cannot find board_env.xml" during kernel compilation flow when a relative path is used to specify the -board-package parameter.
For example: aoc -no-auto-migrate boardtest.cl -o boardtest_a10soc_noautomigrate/boardtest.aocx -board-package=./board/a10soc
To work around this problem use an absolute path for the the board-package.
aoc -no-auto-migrate boardtest.cl -o boardtest_a10soc_noautomigrate/boardtest.aocx -board-package=/<quartus installation>/hld/board/a10soc