conflicting declaration 'arduino::HardwareSerial Serial1'

[acronis2000]

Hi !
Version 3.0.0 throws an error

`
#define Serial1_RX PA10 // Serial1 RX
#define Serial1_TX PA9 // Serial1 TX

HardwareSerial Serial1(Serial1_RX, Serial1_TX);

void setup() {
// put your setup code here, to run once:
}

void loop() {
// put your main code here, to run repeatedly:
}

C:\Users\Admin\AppData\Local\Temp.arduinoIDE-unsaved2026625-8432-6liyya.ubz86\sketch_jul25a\sketch_jul25a.ino:4:16: error: conflicting declaration 'arduino::HardwareSerial Serial1'
4 | HardwareSerial Serial1(Serial1_RX, Serial1_TX);
| ^~~~~~~
In file included from C:\Users\Admin\AppData\Local\Arduino15\packages\STMicroelectronics\hardware\stm32\3.0.0\cores\arduino/WSerial.h:5,
from C:\Users\Admin\AppData\Local\Arduino15\packages\STMicroelectronics\hardware\stm32\3.0.0\cores\arduino/wiring.h:103,
from C:\Users\Admin\AppData\Local\Arduino15\packages\STMicroelectronics\hardware\stm32\3.0.0\cores\arduino/Arduino.h:37,
from C:\Users\Admin\AppData\Local\arduino\sketches\870FFC002468014B87DE5543024610EC\sketch\sketch_jul25a.ino.cpp:1:
C:\Users\Admin\AppData\Local\Arduino15\packages\STMicroelectronics\hardware\stm32\3.0.0\cores\arduino/Serial.h:226:15: note: previous declaration as 'Uart Serial1'
226 | extern Uart Serial1;
| ^~~~~~~
exit status 1

Compilation error: conflicting declaration 'arduino::HardwareSerial Serial1'
`

[fpistm]

Hi @acronis2000
3.0.0 release deployed the ArduinoCore-API.
HardwareSerial has been renamed Uart.

That's why major release number changed. See #2879.