MCU_realloc is a tad ugly but better just to use it for now:
```
MCU_realloc((char **)&MCstacknames, MCnstacks, MCnstacks + 1, sizeof(MCStringRef));
/* UNCHECKED */ MCStringCreateWithCString(v, MCstacknames[MCnstacks++]);
```
Note it takes a char ** pointer as it is expecting a pointer to a data pointer. MCU_realloc doesn't really care what the array is an array of (char * is just used here as a pointer).