The following 2 compiler warnings are only reproducible when setting:
OPTIMIZATION_FLAGS = -Ofast
esp-idf/components/soc/esp32/rtc_clk.c:
In function 'rtc_clk_cpu_freq_get':
esp-idf/components/soc/esp32/rtc_clk.c:506:12:
error: 'freq' may be used uninitialized in this function
[-Werror=maybe-uninitialized]
return freq;
esp-idf/components/esp_ringbuf/ringbuf.c:
In function 'xRingbufferReceiveSplitFromISR':
esp-idf/components/esp_ringbuf/ringbuf.c:934:26:
error: 'pvTempTailItem' may be used uninitialized in this function
[-Werror=maybe-uninitialized]
*ppvTailItem = pvTempTailItem;
Closes https://github.com/espressif/esp-idf/pull/2878
