If I need a pin on an IC to be a constant high, is is 'safe' to connect these to vcc? Or is there some other way that this should be done?

 

If the device is CMOS, that is safe to do. If the pin can be switched to an output, then you need to use a pullup resistor of around 100K to prevent damage should the pin ever get wrongly set.

 

Thanks. That is all I needed to know. The pins are input only (latch enable) on a 4511 chip.