notice: if you are cross build, please follow step
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define SRC_DIR you sdk root dir
SRC_DIR=$($READLINK -f "`dirname $0`")
source $SRC_DIR/megbrain/scripts/cmake-build/utils/utils.sh
build_flatc $SRC_DIR/megbrain false

your build code
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GitOrigin-RevId: ad97860f5ffc1128a8c177f0822c02e240634716