Fixed ModuleInfo generation to no longer use the ModuleInfo class' default initializer for types/defaults, it's unsafe as initializers don't necesarily match the "formal" type. There might be explicit padding. Changed -g switch to emit DW_LANG_D debug info, make demangling work with a patched GDB, still more work to do for full support of D's Dwarf extensions. Added getNullValue helper method.

module bug79;
import std.c.linux.linux;
void main()
{
    timespec ts; 
    ts.tv_nsec -= 1;
    //auto t = ts.tv_nsec - 1;
    //t -= 1;
}