So, I'm using Quartus for a school project but I keep getting this error. Anyone familiar with quartus that could help me?
Info: *******************************************************************
Info: Running Quartus Prime Analysis & Synthesis
Info: Version 15.1.0 Build 185 10/21/2015 SJ Lite Edition
Info: Processing started: Tue Feb 09 23:02:18 2016
Info: Command: quartus_map --read_settings_files=on --write_settings_files=off TOP_VHDL_4BITALU -c TOP_VHDL_4BITALU
Warning (20028): Parallel compilation is not licensed and has been disabled
Info (12021): Found 2 design units, including 1 entities, in source file top_vhdl_4bitalu.vhd
Info (12022): Found design unit 1: TOP_VHDL_4BITALU-Behavioral
Info (12023): Found entity 1: TOP_VHDL_4BITALU
Error (12049): Can't compile duplicate declarations of entity "TOP_VHDL_4BITALU" into library "work"
Error (12180): Instance could be entity "TOP_VHDL_4BITALU" in file TOP_VHDL_4BITALU.vhd compiled in library work
Error (12180): Instance could be entity "TOP_VHDL_4BITALU" in file TOP_VHDL_4BITALU.bdf compiled in library work
Info (12021): Found 1 design units, including 1 entities, in source file top_vhdl_4bitalu.bdf
Error: Quartus Prime Analysis & Synthesis was unsuccessful. 3 errors, 1 warning
Error: Peak virtual memory: 891 megabytes
Error: Processing ended: Tue Feb 09 23:02:30 2016
Error: Elapsed time: 00:00:12
Error: Total CPU time (on all processors): 00:00:27
Error (293001): Quartus Prime Full Compilation was unsuccessful. 5 errors, 1 warning