Stray '\241' in program

I am quite new to ESPhome, I do not know how to solve this compile error:

INFO Installing esphome/AsyncTCP-esphome @ 2.0.1
Unpacking  [####################################]  100%
Library Manager: [email protected] has been installed!
INFO [email protected] has been installed!
Library Manager: Installing esphome/ESPAsyncWebServer-esphome @ 3.1.0
INFO Installing esphome/ESPAsyncWebServer-esphome @ 3.1.0
Unpacking  [####################################]  100%
Library Manager: [email protected] has been installed!
INFO [email protected] has been installed!
Library Manager: Resolving dependencies...
INFO Resolving dependencies...
Library Manager: Installing bblanchon/ArduinoJson @ 6.18.5
INFO Installing bblanchon/ArduinoJson @ 6.18.5
Unpacking  [####################################]  100%
Library Manager: [email protected] has been installed!
INFO [email protected] has been installed!
HARDWARE: ESP32 240MHz, 320KB RAM, 4MB Flash
 - toolchain-xtensa-esp32 @ 8.4.0+2021r2-patch5
Dependency Graph
|-- AsyncTCP-esphome @ 2.0.1
|-- WiFi @ 2.0.0
|-- FS @ 2.0.0
|-- Update @ 2.0.0
|-- ESPAsyncWebServer-esphome @ 3.1.0
|-- ESPmDNS @ 2.0.0
|-- ArduinoJson @ 6.18.5
|-- WiFiClientSecure @ 2.0.0
|-- HTTPClient @ 2.0.0
Compiling .pioenvs/nspanel2/src/esphome/components/adc/adc_sensor.cpp.o
In file included from /data/cache/platformio/packages/toolchain-xtensa-esp32/xtensa-esp32-elf/sys-include/sys/types.h:50,
                 from /data/cache/platformio/packages/framework-arduinoespressif32/tools/sdk/esp32/include/newlib/platform_include/pthread.h:17,
                 from /data/cache/platformio/packages/toolchain-xtensa-esp32/xtensa-esp32-elf/include/c++/8.4.0/xtensa-esp32-elf/no-rtti/bits/gthr-default.h:48,
                 from /data/cache/platformio/packages/toolchain-xtensa-esp32/xtensa-esp32-elf/include/c++/8.4.0/xtensa-esp32-elf/no-rtti/bits/gthr.h:151,
                 from /data/cache/platformio/packages/toolchain-xtensa-esp32/xtensa-esp32-elf/include/c++/8.4.0/ext/atomicity.h:35,
                 from /data/cache/platformio/packages/toolchain-xtensa-esp32/xtensa-esp32-elf/include/c++/8.4.0/bits/basic_string.h:39,
                 from /data/cache/platformio/packages/toolchain-xtensa-esp32/xtensa-esp32-elf/include/c++/8.4.0/string:52,
                 from src/esphome/core/component.h:3,
                 from src/esphome/components/adc/adc_sensor.h:3,
                 from src/esphome/components/adc/adc_sensor.cpp:1:
/data/cache/platformio/packages/framework-arduinoespressif32/tools/sdk/esp32/include/newlib/platform_include/sys/select.h:1:1: error: stray '\241' in program
Compiling .pioenvs/nspanel2/src/esphome/components/api/api_connection.cpp.o
Compiling .pioenvs/nspanel2/src/esphome/components/api/api_frame_helper.cpp.o
Compiling .pioenvs/nspanel2/src/esphome/components/api/api_pb2.cpp.o

There is no explicit error message given, it is just stopping.

Thank for any hint,
Christof

Well. I did a re-install of ESPHome and this solved the problem. Maybe I had a problem with (SD?) storage