reset pin not activated properly on stm32 bluepill

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setup: I am using STM32 to drive an ssd1306 display with 128x64 pixels. The reset pin is connected to PA3.
Observation: The display is not going out of reset even when calling Adafruit_SSD1306::begin with reset param = true.
Analysis: PA3 in STM32 is assigned to pin number 0xC3 (-61) which is higher than 80 -> sign bit is 1.
In Adafruit_SSD1306::begin, the code is doing 'rstPin >= 0' to check if reset pin was configured. rstPin value is -61, therefore it is considered as not configured and the library is not resetting the display.
Solution: replace 'if (reset && (rstPin >= 0))' by 'if (reset && (rstPin != -1))' in Adafruit_SSD1306::begin