Building error: unknown type name 'size_t'

[prashanthumbre4]

Hello,
I am facing this issue from yesterday. It was working perfectly from last 2-3 months until yesterday afternoon and without any change in my code bulk errors are popping up while building the project.
Approximately 400-500 same kind of errors are popping up.

After that, I close my current project and open an example project of gatt_server in Bluetooth(just because this was the base of my project and it was working fine). But still, the same errors are there.

My observations:
- stddef.h not getting recognised.
- Yesterday espressif updated esp-idf on the master branch, maybe after that, I am facing this issue.
- Attaching the logs of example project after the clean build.
- I also downloaded a fresh copy of esp-idf and set up the same but didn't work.