Thanks for your reply.
Not sure. I’m using esp8266 v3.0.2 from the boards manager. How do I find my xtensa version?
EDIT: in the Arduino log I see “10.3-1757bed” which matches the toolchain version listed against the Espressif 8266 platform.
As far as I can tell, yes. There are a lot fewer libraries in this than I thought.
C:\Program Files (x86)\Arduino\arduino-builder -dump-prefs -logger=machine -hardware C:\Program Files (x86)\Arduino\hardware -hardware C:\Users\Someone\AppData\Local\Arduino15\packages -tools C:\Program Files (x86)\Arduino\tools-builder -tools C:\Program Files (x86)\Arduino\hardware\tools\avr -tools C:\Users\Someone\AppData\Local\Arduino15\packages -built-in-libraries C:\Program Files (x86)\Arduino\libraries -libraries D:\Someone\Documents\Arduino\libraries -fqbn=esp8266:esp8266:d1_mini:xtal=80,vt=flash,exception=disabled,stacksmash=disabled,ssl=all,mmu=3232,non32xfer=fast,eesz=4M3M,ip=lm2f,dbg=Disabled,lvl=None____,wipe=none,baud=921600 -vid-pid=1A86_7523 -ide-version=10813 -build-path C:\Users\Someone\AppData\Local\Temp\arduino_build_730264 -warnings=none -build-cache C:\Users\Someone\AppData\Local\Temp\arduino_cache_431172 -prefs=build.warn_data_percentage=75 -prefs=runtime.tools.xtensa-lx106-elf-gcc.path=C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\tools\xtensa-lx106-elf-gcc\3.0.4-gcc10.3-1757bed -prefs=runtime.tools.xtensa-lx106-elf-gcc-3.0.4-gcc10.3-1757bed.path=C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\tools\xtensa-lx106-elf-gcc\3.0.4-gcc10.3-1757bed -prefs=runtime.tools.mklittlefs.path=C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\tools\mklittlefs\3.0.4-gcc10.3-1757bed -prefs=runtime.tools.mklittlefs-3.0.4-gcc10.3-1757bed.path=C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\tools\mklittlefs\3.0.4-gcc10.3-1757bed -prefs=runtime.tools.python3.path=C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\tools\python3\3.7.2-post1 -prefs=runtime.tools.python3-3.7.2-post1.path=C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\tools\python3\3.7.2-post1 -prefs=runtime.tools.mkspiffs.path=C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\tools\mkspiffs\3.0.4-gcc10.3-1757bed -prefs=runtime.tools.mkspiffs-3.0.4-gcc10.3-1757bed.path=C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\tools\mkspiffs\3.0.4-gcc10.3-1757bed -verbose D:\Someone\Documents\github\core\ESP_IoT_Core\ESP_IoT_Core.ino
C:\Program Files (x86)\Arduino\arduino-builder -compile -logger=machine -hardware C:\Program Files (x86)\Arduino\hardware -hardware C:\Users\Someone\AppData\Local\Arduino15\packages -tools C:\Program Files (x86)\Arduino\tools-builder -tools C:\Program Files (x86)\Arduino\hardware\tools\avr -tools C:\Users\Someone\AppData\Local\Arduino15\packages -built-in-libraries C:\Program Files (x86)\Arduino\libraries -libraries D:\Someone\Documents\Arduino\libraries -fqbn=esp8266:esp8266:d1_mini:xtal=80,vt=flash,exception=disabled,stacksmash=disabled,ssl=all,mmu=3232,non32xfer=fast,eesz=4M3M,ip=lm2f,dbg=Disabled,lvl=None____,wipe=none,baud=921600 -vid-pid=1A86_7523 -ide-version=10813 -build-path C:\Users\Someone\AppData\Local\Temp\arduino_build_730264 -warnings=none -build-cache C:\Users\Someone\AppData\Local\Temp\arduino_cache_431172 -prefs=build.warn_data_percentage=75 -prefs=runtime.tools.xtensa-lx106-elf-gcc.path=C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\tools\xtensa-lx106-elf-gcc\3.0.4-gcc10.3-1757bed -prefs=runtime.tools.xtensa-lx106-elf-gcc-3.0.4-gcc10.3-1757bed.path=C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\tools\xtensa-lx106-elf-gcc\3.0.4-gcc10.3-1757bed -prefs=runtime.tools.mklittlefs.path=C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\tools\mklittlefs\3.0.4-gcc10.3-1757bed -prefs=runtime.tools.mklittlefs-3.0.4-gcc10.3-1757bed.path=C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\tools\mklittlefs\3.0.4-gcc10.3-1757bed -prefs=runtime.tools.python3.path=C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\tools\python3\3.7.2-post1 -prefs=runtime.tools.python3-3.7.2-post1.path=C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\tools\python3\3.7.2-post1 -prefs=runtime.tools.mkspiffs.path=C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\tools\mkspiffs\3.0.4-gcc10.3-1757bed -prefs=runtime.tools.mkspiffs-3.0.4-gcc10.3-1757bed.path=C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\tools\mkspiffs\3.0.4-gcc10.3-1757bed -verbose D:\Someone\Documents\github\core\ESP_IoT_Core\ESP_IoT_Core.ino
Using board 'd1_mini' from platform in folder: C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\3.0.2
Using core 'esp8266' from platform in folder: C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\3.0.2
Detecting libraries used...
"C:\\Users\\Someone\\AppData\\Local\\Arduino15\\packages\\esp8266\\tools\\xtensa-lx106-elf-gcc\\3.0.4-gcc10.3-1757bed/bin/xtensa-lx106-elf-g++" -D__ets__ -DICACHE_FLASH -U__STRICT_ANSI__ -D_GNU_SOURCE "-IC:\\Users\\Someone\\AppData\\Local\\Arduino15\\packages\\esp8266\\hardware\\esp8266\\3.0.2/tools/sdk/include" "-IC:\\Users\\Someone\\AppData\\Local\\Arduino15\\packages\\esp8266\\hardware\\esp8266\\3.0.2/tools/sdk/lwip2/include" "-IC:\\Users\\Someone\\AppData\\Local\\Arduino15\\packages\\esp8266\\hardware\\esp8266\\3.0.2/tools/sdk/libc/xtensa-lx106-elf/include" "-IC:\\Users\\Someone\\AppData\\Local\\Temp\\arduino_build_730264/core" -c -w -Werror=return-type -Os -g -free -fipa-pta -mlongcalls -mtext-section-literals -fno-rtti -falign-functions=4 -std=gnu++17 -ffunction-sections -fdata-sections -fno-exceptions -DMMU_IRAM_SIZE=0x8000 -DMMU_ICACHE_SIZE=0x8000 -w -x c++ -E -CC -DNONOSDK22x_190703=1 -DF_CPU=80000000L -DLWIP_OPEN_SRC -DTCP_MSS=536 -DLWIP_FEATURES=1 -DLWIP_IPV6=0 -DARDUINO=10813 -DARDUINO_ESP8266_WEMOS_D1MINI -DARDUINO_ARCH_ESP8266 "-DARDUINO_BOARD=\"ESP8266_WEMOS_D1MINI\"" "-DBOARD_VARIANT=\"d1_mini\"" "-DBOARD_FLASH_SIZE=\"4M\"" -DFLASHMODE_DIO -DESP8266 "-IC:\\Users\\Someone\\AppData\\Local\\Arduino15\\packages\\esp8266\\hardware\\esp8266\\3.0.2\\cores\\esp8266" "-IC:\\Users\\Someone\\AppData\\Local\\Arduino15\\packages\\esp8266\\hardware\\esp8266\\3.0.2\\variants\\d1_mini" "C:\\Users\\Someone\\AppData\\Local\\Temp\\arduino_build_730264\\sketch\\ESP_IoT_Core.ino.cpp" -o nul -DARDUINO_LIB_DISCOVERY_PHASE
...
"C:\\Users\\Someone\\AppData\\Local\\Arduino15\\packages\\esp8266\\tools\\python3\\3.7.2-post1/python3" -I "C:\\Users\\Someone\\AppData\\Local\\Arduino15\\packages\\esp8266\\hardware\\esp8266\\3.0.2/tools/elf2bin.py" --eboot "C:\\Users\\Someone\\AppData\\Local\\Arduino15\\packages\\esp8266\\hardware\\esp8266\\3.0.2/bootloaders/eboot/eboot.elf" --app "C:\\Users\\Someone\\AppData\\Local\\Temp\\arduino_build_730264/ESP_IoT_Core.ino.elf" --flash_mode dio --flash_freq 40 --flash_size 4M --path "C:\\Users\\Someone\\AppData\\Local\\Arduino15\\packages\\esp8266\\tools\\xtensa-lx106-elf-gcc\\3.0.4-gcc10.3-1757bed/bin" --out "C:\\Users\\Someone\\AppData\\Local\\Temp\\arduino_build_730264/ESP_IoT_Core.ino.bin"
Creating BIN file "C:\Users\Someone\AppData\Local\Temp\arduino_build_730264/ESP_IoT_Core.ino.bin" using "C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\3.0.2/bootloaders/eboot/eboot.elf" and "C:\Users\Someone\AppData\Local\Temp\arduino_build_730264/ESP_IoT_Core.ino.elf"
"C:\\Users\\Someone\\AppData\\Local\\Arduino15\\packages\\esp8266\\tools\\python3\\3.7.2-post1/python3" -I "C:\\Users\\Someone\\AppData\\Local\\Arduino15\\packages\\esp8266\\hardware\\esp8266\\3.0.2/tools/signing.py" --mode sign --privatekey "D:\\Someone\\Documents\\github\\core\\ESP_IoT_Core/private.key" --bin "C:\\Users\\Someone\\AppData\\Local\\Temp\\arduino_build_730264/ESP_IoT_Core.ino.bin" --out "C:\\Users\\Someone\\AppData\\Local\\Temp\\arduino_build_730264/ESP_IoT_Core.ino.bin.signed" --legacy "C:\\Users\\Someone\\AppData\\Local\\Temp\\arduino_build_730264/ESP_IoT_Core.ino.bin.legacy_sig"
"C:\\Users\\Someone\\AppData\\Local\\Arduino15\\packages\\esp8266\\tools\\python3\\3.7.2-post1/python3" -I "C:\\Users\\Someone\\AppData\\Local\\Arduino15\\packages\\esp8266\\hardware\\esp8266\\3.0.2/tools/sizes.py" --elf "C:\\Users\\Someone\\AppData\\Local\\Temp\\arduino_build_730264/ESP_IoT_Core.ino.elf" --path "C:\\Users\\Someone\\AppData\\Local\\Arduino15\\packages\\esp8266\\tools\\xtensa-lx106-elf-gcc\\3.0.4-gcc10.3-1757bed/bin" --mmu "-DMMU_IRAM_SIZE=0x8000 -DMMU_ICACHE_SIZE=0x8000"
Executable segment sizes:
ICACHE : 32768 - flash instruction cache
IROM : 397196 - code in flash (default or ICACHE_FLASH_ATTR)
IRAM : 28777 / 32768 - code in IRAM (IRAM_ATTR, ISRs...)
DATA : 1528 ) - initialized variables (global, static) in RAM/HEAP
RODATA : 9540 ) / 81920 - constants (global, static) in RAM/HEAP
BSS : 26032 ) - zeroed variables (global, static) in RAM/HEAP
Using library LittleFS at version 0.1.0 in folder: C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\3.0.2\libraries\LittleFS
Using library ArduinoJson at version 6.19.4 in folder: D:\Someone\Documents\Arduino\libraries\ArduinoJson
Using library ESPAsyncTCP at version 1.2.2 in folder: D:\Someone\Documents\Arduino\libraries\ESPAsyncTCP
Using library ESPAsyncWebServer at version 1.2.3 in folder: D:\Someone\Documents\Arduino\libraries\ESPAsyncWebServer
Using library ESP8266WiFi at version 1.0 in folder: C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\3.0.2\libraries\ESP8266WiFi
Using library Hash at version 1.0 in folder: C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\3.0.2\libraries\Hash
Using library QList at version 0.6.7 in folder: D:\Someone\Documents\Arduino\libraries\QList
Using library NeoPixelBus_by_Makuna at version 2.6.9 in folder: D:\Someone\Documents\Arduino\libraries\NeoPixelBus_by_Makuna
Using library SPI at version 1.0 in folder: C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\3.0.2\libraries\SPI
Using library ESP8266HTTPClient at version 1.2 in folder: C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\3.0.2\libraries\ESP8266HTTPClient
Using library ESP8266httpUpdate at version 1.3 in folder: C:\Users\Someone\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\3.0.2\libraries\ESP8266httpUpdate
"C:\\Users\\Someone\\AppData\\Local\\Arduino15\\packages\\esp8266\\tools\\xtensa-lx106-elf-gcc\\3.0.4-gcc10.3-1757bed/bin/xtensa-lx106-elf-size" -A "C:\\Users\\Someone\\AppData\\Local\\Temp\\arduino_build_730264/ESP_IoT_Core.ino.elf"
Sketch uses 437041 bytes (41%) of program storage space. Maximum is 1044464 bytes.
Global variables use 37100 bytes (45%) of dynamic memory, leaving 44820 bytes for local variables. Maximum is 81920 bytes.
Unfortunately the log is too long so i snipped out the middle. Apparently the full log exceeds the limits of a post here and on pastebin.
This is basically my first embedded project so I’m still working things out as I go.