rasql - segfault with dem() function

[Bang Pham Huu]

This problem is due to missing option for dem() function. Here it has segfault error:

Request: 'select dem(c) from test_mr as c'... parsing... checking semantics... evaluating...  [INFO] - 2020-05-11 14:01:58,484: r_Conv_DEM::convertTo(NULL)
 [INFO] - 2020-05-11 14:01:58,484: r_Conv_DEM::convertTo(...) src interval=[0:59,0:39]
 [INFO] - 2020-05-11 14:01:58,484: r_Conv_DEM::convertTo(...) src type=char
 [INFO] - 2020-05-11 14:01:58,484: r_Conv_DEM::decodeOptions(NULL)
[ERROR] - 2020-05-11 14:01:58,484, conversion/dem.cc:132: r_Conv_DEM::decodeOptions(...) Error: Some required options are missing!
[ERROR] - 2020-05-11 14:01:58,485, server/rasserver_main.cc:114: Interrupted by signal SIGSEGV (Invalid memory access at address 0)... stacktrace:
 [1] ??:0 in fclose+0x4 [0x7f59b1206f84]
 [2] /home/rasdaman/rasdaman_community/install/bin/rasserver() [0x55b7d8]
 [3] /home/rasdaman/rasdaman_community/install/bin/rasserver() [0x4af645]
 [4] /home/rasdaman/rasdaman_community/install/bin/rasserver() [0x48579c]
 [5] /home/rasdaman/rasdaman_community/install/bin/rasserver() [0x46c86d]
 [6] /home/rasdaman/rasdaman_community/install/bin/rasserver() [0x44a9b4]
 [7] /home/rasdaman/rasdaman_community/install/bin/rasserver() [0x423bd6]
 [8] /home/rasdaman/rasdaman_community/install/bin/rasserver() [0x756cb6]
 [9] /home/rasdaman/rasdaman_community/install/bin/rasserver() [0x706e26]
[10] /home/rasdaman/rasdaman_community/install/bin/rasserver() [0x7168f4]
[11] /home/rasdaman/rasdaman_community/install/bin/rasserver() [0x71fd51]
[12] /home/rasdaman/rasdaman_community/install/bin/rasserver() [0x85b89e]
[13] /home/rasdaman/rasdaman_community/install/bin/rasserver() [0x85dd0b]
[14] /home/rasdaman/rasdaman_community/install/bin/rasserver() [0x85de1c]
[15] /lib64/libstdc++.so.6(+0xb5070) [0x7f59b64db070]
[16] /lib64/libpthread.so.0(+0x7dd5) [0x7f59b6938dd5]
[17] ??:0 in clone+0x6d [0x7f59b129702d]

[ERROR] - 2020-05-11 14:01:58,526, server/rasserver_main.cc:117: Shutting down... rasserver terminated.