some xdc compiler error

This error occurs when xdc runs close function but it finds that "Program.system" is null.  Here is the code from xdc/runtime/package.xs:

    /* system cannot be NULL if target modules are present */
    if (Program.system === null) {
        for (var i = 0; i < xdc.om.$modules.length; i++) {
            var mod = xdc.om.$modules[i];
            if (mod.$used && !mod.$hostonly) {
                Program.$logError("target modules are present, but Program.system == null", Program);
                return;
            }
        }
    }

As the comment says, I think you should check whether your target(ti.targets.C64+) is set properly  while running xdc tools.

[edit] For more information on XDC, please refer to XDC Consumer User's Guide

Thanks for Lorry~

Our problem is solved, because each SDK(XDAIS FRAMEWORK,DSP/BIOS, CGT,  ) has some different  dependency, so we made this mistake, Actually, we just re-dowload all  SDK software (DVSDK) that can be solved this problem. 

Here I have some questions for XDC:

1) xdc/runtime/package.xs:   what does "xdc.om" refer to?

2) I know "Program" is an module of XDC, it just like a class in C++. Could anyone tell me where "Program.system" get its value?

3) From a beginner perspective, I find that there are lots of  "xdc"  "xs"  "mak" "bld" "opt" ...  files in dvevm_x_xx  folder.  Could anyone provide me a shortcut to remember the function of these files.  Because I spend much time in writing codec and debug it, however, every time when I see these files again, I think I've forgotten the meaning of them. So I have to back to documents to learn them.  And some of them is related with my codec code or the process of compilation

I want to know if it is necessary to set so many files,  if it is possible to simplify them to just three or four  types of files, I think,  that will be better for understanding.  For example: " .c",".h",".xdc",".ini".