JS_ReportError(cx, "internal error compiling %s: stack underflow at pc %d", cg->filename ? cg->filename : "stdin", target);
char numBuf[12]; sprintf(numBuf, "%d", target); JS_ReportErrorNumber(cx, NULL, JSMSG_STACK_UNDERFLOW, cg->filename ? cg->filename : "stdin", numBuf);
UpdateDepth(JSContext *cx, JSCodeGenerator *cg, ptrdiff_t target){    jsbytecode *pc;    JSCodeSpec *cs;    intN nuses;    pc = CG_CODE(cg, target);    cs = &js_CodeSpec[pc[0]];    nuses = cs->nuses;    if (nuses < 0)        nuses = 2 + GET_ARGC(pc);	/* stack: fun, this, [argc arguments] */    cg->stackDepth -= nuses;    if (cg->stackDepth < 0) {        JS_ReportError(cx,		       "internal error compiling %s: stack underflow at pc %d",		       cg->filename ? cg->filename : "stdin", target);    }    cg->stackDepth += cs->ndefs;    if ((uintN)cg->stackDepth > cg->maxStackDepth)        cg->maxStackDepth = cg->stackDepth;}