esp32: Reduce binary size of RISC-V boards including ESP32-C6 #17994
+18
−0
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Summary
This PR switches all esp32 RISC-V boards to optimise for size (-0s) instead of performance (-O2). This also reduces the static D/IRAM usage, which translates to more free RAM at runtime.
On ESP32-C6 this PR also switches to using the SPI flash driver from ROM, which saves about an extra 10KB of flash. There is some risk of a regression due to this change, but we already use this option on ESP32-C2 so it should be safe enough.
Testing
Trade-offs and Alternatives