ESP32 Arduino core gives less available RAM on ESP32-S2

[technoblogy]

I tested the latest release of uLisp on an ESP32-S2 board (Adafruit ESP32-S2 Feather) with the current Arduino core, 2.0.9, and found I have over 8Kbytes less available RAM than under the previous core I tested, 2.0.5.

This doesn't seem to happen with ESP32 boards (eg Adafruit ESP32 Feather).

In ESP uLisp release 4.4d I've therefore reduced the amount of Lisp workspace on the ESP32-S2 boards from 9216 objects to 8160 objects. Otherwise compilation fails with the error:

error: ld returned 1 exit status

I've tried to track down what's causing this, but without success. I suspect it may be the Wi-Fi libraries.

Can anyone can shed any light on this?