make -f makefile.unix
Building LevelDB ...
/bin/sh: 1: ./build_detect_platform: Permission denied
make[1]: Entering directory `/home/mobgod/megacoin-0.8.992-source/src/leveldb'
Makefile:18: build_config.mk: No such file or directory
make[1]: *** No rule to make target `build_config.mk'. Stop.
make[1]: Leaving directory `/home/mobgod/megacoin-0.8.992-source/src/leveldb'
make: *** [leveldb/libleveldb.a] Error 2
chmod 755 src/leveldb/build_detect_platform
ya that should fix the issue
chmod 755 src/leveldb/build_detect_platform
chmod: cannot access `src/leveldb/build_detect_platform': No such file or directory
chmod 755 ~/megacoin/src/leveldb/build_detect_platform <---works