Error on Quartus 12

[Altera_Forum]

Hi, all. The project was created by Quartus 10, and it has been compiled successfully. But when I try to compile it on Quartus 12, it has an error as follow. 

Anyone can help me to explain the problem and give some suggestions to solve it? Thank you very much!    --- Quote Start ---  Internal Error: Sub-system: QTL, File: /quartus/h/qtl_bool_vector_sys.h, Line: 333 index >= 0 && (QTL_BOOL_VECTOR::size_type)index < this->m_size Stack Trace:  0x262d: err_report_internal_error + 0x2d (CCL_ERR)  0x18840: QTL_BOOL_VECTOR::operator[] + 0xe7c0 (ccl_qtl)  0x15326: OPT_RAM_AI::OPT_RAM_AI + 0x11e76 (SYNTH_INFER)  0xbfa8: OPT_RAM_AI::OPT_RAM_AI + 0x8af8 (SYNTH_INFER)  0xa4a9: OPT_RAM_AI::OPT_RAM_AI + 0x6ff9 (SYNTH_INFER)  0x9735: OPT_RAM_AI::OPT_RAM_AI + 0x6285 (SYNTH_INFER)  0x14411b: opt_sea_of_mux + 0xd9b0b (SYNTH_OPT)  0x14739b: opt_sea_of_mux + 0xdcd8b (SYNTH_OPT)  0x142d74: opt_sea_of_mux + 0xd8764 (SYNTH_OPT)  0x3bdd: RTL_ROOT::RTL_ROOT + 0x2bdd (SYNTH_OPT)  0x4723: RTL_ROOT::process_sgate_netlist + 0x533 (SYNTH_OPT)  0x152808: sgn_clear_check_ip_functor + 0xbf5a8 (synth_sgn)  0x153ed2: sgn_clear_check_ip_functor + 0xc0c72 (synth_sgn)  0xae192: sgn_clear_check_ip_functor + 0x1af32 (synth_sgn)  0xb0d54: sgn_clear_check_ip_functor + 0x1daf4 (synth_sgn)  0xb1750: sgn_clear_check_ip_functor + 0x1e4f0 (synth_sgn)  0x10c2b: sgn_qic_full + 0x23b (synth_sgn)     0x1297b: qexe_get_tcl_sub_option + 0x1f2b (comp_qexe)  0x15bad: qexe_process_cmdline_arguments + 0x5ad (comp_qexe)  0x15cc1: qexe_standard_main + 0xa1 (comp_qexe)   0x17b8: MSG_INITIALIZER::~MSG_INITIALIZER + 0x118 (CCL_MSG)  0x175c: MSG_INITIALIZER::~MSG_INITIALIZER + 0xbc (CCL_MSG)  0x3c04: MEM_SEGMENT_INTERNAL::free_interthread_delete_queue + 0x94 (ccl_mem)  0x2d20f: msg_exe_main + 0x8f (CCL_MSG)   0x196ab: BaseProcessStart + 0x2b (kernel32)  End-trace  Quartus II 64-Bit Version 12.0 Build 178 05/31/2012 SJ Full Version  --- Quote End ---  

[Altera_Forum]

try cleaning your project by deleting the "db" and "db_incremental" folders and compile again.

[Altera_Forum]

Yeah, I tried. But it doesn't work.

[Altera_Forum]

I ran into a bunch of internal errors on 12.0 and 12.0Sp1, less so on 12.0Sp2. I'd recommend trying an upgrade.

[Altera_Forum]

if the upgrade doesnt work, raise a support request with altera via mysupport.

[Altera_Forum]

I encounter many crashes too. 

Some were due to the fact that somemegawizards functions were not upgraded, others that in my top sdc constraint file, little sdc scripts in sub directories were executed without going back to the project directory after that. Try to compile with a very light sdc file for example.

[Altera_Forum]

--- Quote Start ---  I ran into a bunch of internal errors on 12.0 and 12.0Sp1, less so on 12.0Sp2. I'd recommend trying an upgrade.  --- Quote End ---   Thank you for your suggestion. I tried an upgrade. The same error happens again. Some of my codes are system verilog. I don't if it is caused by the incompatibility of System Verilog.