Summary of difference points for GDB
The ported version of GDB for VE provides the functionality of source level debugging and symbolic debugging of a VE
program written in C, C++ or Fortran language. You can insert a break point specifying a source line or a symbol of a
function, start a VE program, attach GDB to an already running VE process, step through a VE program, examine a variable
specifying a symbol, examine a scalar or vector register, change a variable or  a register, and invoke a function of a VE
program. You can also analyze a core file of a VE program.
There are the following difference points between the ported version of GDB for VE and GDB for Linux:
1.  GDB internally executes "ve_exec" command with "--traceme" option in order to execute VE program.
2. VE_NODE_NUMBER environment variable can be used to specify VE node to execute VE program.
If the environment variable is not set, VE program is executed on VE node 0.
3. Only local debugging is supported. Remote debugging using GDB server or GDB stub is not supported.
4. The directory where separate debug symbols are searched for is "/opt/nec/ve/lib/debug".
5. GDB can not deals with thread-local variables correctly, because DWARF information about them is invalid.
6. The following commands don't show information for VE side but show for VH(Vector Host) side using procfs of it.
info proc
info proc all
info proc cmdline
info proc cwd
info proc exe
info proc mappings
info proc stat
info proc status
7. "info auxv" command is available only in debugging with core file.
8. GDB and VEOS does not handle invocation of execve() system call from a VE program properly.
When a VE program invokes execve() system call, GDB detects SIGTRAP , or can not find the process or the thread
 , and then it does not reload a new program.
In this case, "quit" command need to be executed to terminate GDB.  
The debugged process will be killed when GDB terminates, if it have been executed from GDB .
9. "call" command can be used to invoke a function of a VE program. But, if stack area beyond page boundary
is required, "call" command fails due to access error.
10. VE specific commands are added.
See "VE specific commands" sheet.
11. Some of commands are not supported. 
See "GDB commands" sheet and "MI commands".
12. Instruction Counter (IC) will be far from the address which causes a HW exception when the program is
stopped by the HW exception.
"advance off" mode can be set in order to check the precise state when HW exception occurs.
In this mode, instruction execution is held until the preceding instructions have completed.
As the result, GDB shows the precise state when HW exception occurs.
See "How to set advance off mode" sheet.