Using Github Actions to evaluate Flash / RAM size constraints, when using C++ features in ESP-IDF Projects

Results

ESP-IDF Version 5.4

ESP32S3

Feature	D/IRAM	diff to base	Flash	diff to base	Heap alloc	diff to base
(base C)	54283	0	138998	0	13500	0
string	54435	152	144806	5808	13596	96
vector	54435	152	143590	4592	13596	96
exceptions	54587	304	165746	26748	14752	1252
iostream	60627	6344	354102	215104	13676	176

Notes

ESP-IDF C++ Support doc

Exceptions

Exception-throwing code should never be used in real-time critical code paths. C++ Exceptions should only be used for exceptional cases, i.e., something happening unexpectedly and occurs rarely.

iostream

Simply including <iostream> header in one of the source files significantly increases the binary size by about 200 kB. (Keep C based ESP_LOG module for logging)