v.add_decl("void show_backtrace (int signo) \{")
if not modelbuilder.toolcontext.opt_no_stacktrace.value then
+ v.add_decl("if(signo == 0)\{exit(0);\}")
v.add_decl("char* opt = getenv(\"NIT_NO_STACK\");")
v.add_decl("unw_cursor_t cursor;")
v.add_decl("if(opt==NULL)\{")