error in paste mode

[dhalbert]

Reproducible on ESP32-C3 and ESP32-C6:

A code error during paste mode or raw mode causes a hard crash when exiting the mode with ctrl-D.

This does not occur when using the regular REPL input mode.

Simplest example (x is an unassigned variable):

Adafruit CircuitPython 10.0.0-alpha.2 on 2025-04-04; Adafruit QT Py ESP32C3 with ESP32-C3FN4
>>> 
paste mode; Ctrl-C to cancel, Ctrl-D to finish
=== x
=== [type ctrl-D here]
ESP-ROM:esp32c3-api1-20210207
Build:Feb  7 2021
rst:0xc (RTC_SW_CPU_RST),boot:0xd (SPI_FAST_FLASH_BOOT)
Saved PC:0x40382ab0
SPIWP:0xee
mode:DIO, clock div:1
load:0x3fcd5820,len:0x120
load:0x403cc710,len:0x900
load:0x403ce710,len:0x2178
entry 0x403cc710

Auto-reload is off.
Running in safe mode! Not running saved code.

You are in safe mode because:
CircuitPython core code crashed hard. Whoops!
Hard fault: memory access or instruction error.
Please file an issue with your program at github.com/adafruit/circuitpython/issues.
Press reset to exit safe mode.

Press any key to enter the REPL. Use CTRL-D to reload.

One hypothesis is that the ctrl-D causes an EOF exception during read, and so there is a double exception (the first is due to the code error).

This does not occur on boards with native USB CDC REPL. The only such boards I have to test right now are ESP32-C3 and ESP32-C6, which are RISCV, but that may be a coincidence. Or it may be due to nlr handling on RISCV.

EDITS:

Could not reproduce on ESP32 Feather HUZZAH32 or V2, or micro:bit V2, so it's not just serial-only boards.

1/0 is also a very simple error. Interestingly, raise ValueError or similar does not provoke the crash.