Build failures under Arduino 1.8

[dlchambers]

It seems like there are issues with Arduino 2.x :) so I switched to 1.8.
Using megaTinyCore for an ATTiny404, and when I build I get an error.
Any ideas?

Arduino: 1.8.12 (Windows 10), TD: 1.51, Board: "ATtiny3224/1624/1614/1604/824/814/804/424/414/404/214/204, ATtiny404, 20 MHz internal, 1.8V (5 MHz or less), Disabled/Disabled, EEPROM retained, Enabled (default timer), 8ms, Master or Slave (saves flash and RAM), Default (doesn't print floats, 1.4k flash use), PB0-2, PA3-5 (default), On all pins, with new implementation., Disabled (recommended), No delay before window "opens""

C:\Program Files (x86)\Arduino\arduino-builder -dump-prefs -logger=machine -hardware C:\Program Files (x86)\Arduino\hardware -hardware C:\Users\dlcha\AppData\Local\Arduino15\packages -tools C:\Program Files (x86)\Arduino\tools-builder -tools C:\Program Files (x86)\Arduino\hardware\tools\avr -tools C:\Users\dlcha\AppData\Local\Arduino15\packages -built-in-libraries C:\Program Files (x86)\Arduino\libraries -libraries C:\Users\dlcha\Documents\Arduino\libraries -fqbn=megaTinyCore:megaavr:atxy4:chip=404,clock=20internal,bodvoltage=1v8,bodmode=disabled,eesave=enable,millis=enabled,startuptime=8,wiremode=mors,printf=default,PWMmux=default,attach=allenabled,WDTtimeout=disabled,WDTwindow=disabled -ide-version=10812 -build-path C:\Users\dlcha\AppData\Local\Temp\arduino_build_416067 -warnings=none -build-cache C:\Users\dlcha\AppData\Local\Temp\arduino_cache_283460 -prefs=build.warn_data_percentage=75 -prefs=runtime.tools.avr-gcc.path=C:\Users\dlcha\AppData\Local\Arduino15\packages\DxCore\tools\avr-gcc\7.3.0-atmel3.6.1-azduino7b1 -prefs=runtime.tools.avr-gcc-7.3.0-atmel3.6.1-azduino7b1.path=C:\Users\dlcha\AppData\Local\Arduino15\packages\DxCore\tools\avr-gcc\7.3.0-atmel3.6.1-azduino7b1 -prefs=runtime.tools.python3.path=C:\Users\dlcha\AppData\Local\Arduino15\packages\megaTinyCore\tools\python3\3.7.2-post1 -prefs=runtime.tools.python3-3.7.2-post1.path=C:\Users\dlcha\AppData\Local\Arduino15\packages\megaTinyCore\tools\python3\3.7.2-post1 -prefs=runtime.tools.arduinoOTA.path=C:\Users\dlcha\AppData\Local\Arduino15\packages\arduino\tools\arduinoOTA\1.3.0 -prefs=runtime.tools.arduinoOTA-1.3.0.path=C:\Users\dlcha\AppData\Local\Arduino15\packages\arduino\tools\arduinoOTA\1.3.0 -prefs=runtime.tools.avrdude.path=C:\Users\dlcha\AppData\Local\Arduino15\packages\DxCore\tools\avrdude\6.3.0-arduino17or18 -prefs=runtime.tools.avrdude-6.3.0-arduino17or18.path=C:\Users\dlcha\AppData\Local\Arduino15\packages\DxCore\tools\avrdude\6.3.0-arduino17or18 -verbose C:\Users\dlcha\Documents\Arduino\ds3231\ds3231.ino
C:\Program Files (x86)\Arduino\arduino-builder -compile -logger=machine -hardware C:\Program Files (x86)\Arduino\hardware -hardware C:\Users\dlcha\AppData\Local\Arduino15\packages -tools C:\Program Files (x86)\Arduino\tools-builder -tools C:\Program Files (x86)\Arduino\hardware\tools\avr -tools C:\Users\dlcha\AppData\Local\Arduino15\packages -built-in-libraries C:\Program Files (x86)\Arduino\libraries -libraries C:\Users\dlcha\Documents\Arduino\libraries -fqbn=megaTinyCore:megaavr:atxy4:chip=404,clock=20internal,bodvoltage=1v8,bodmode=disabled,eesave=enable,millis=enabled,startuptime=8,wiremode=mors,printf=default,PWMmux=default,attach=allenabled,WDTtimeout=disabled,WDTwindow=disabled -ide-version=10812 -build-path C:\Users\dlcha\AppData\Local\Temp\arduino_build_416067 -warnings=none -build-cache C:\Users\dlcha\AppData\Local\Temp\arduino_cache_283460 -prefs=build.warn_data_percentage=75 -prefs=runtime.tools.avr-gcc.path=C:\Users\dlcha\AppData\Local\Arduino15\packages\DxCore\tools\avr-gcc\7.3.0-atmel3.6.1-azduino7b1 -prefs=runtime.tools.avr-gcc-7.3.0-atmel3.6.1-azduino7b1.path=C:\Users\dlcha\AppData\Local\Arduino15\packages\DxCore\tools\avr-gcc\7.3.0-atmel3.6.1-azduino7b1 -prefs=runtime.tools.python3.path=C:\Users\dlcha\AppData\Local\Arduino15\packages\megaTinyCore\tools\python3\3.7.2-post1 -prefs=runtime.tools.python3-3.7.2-post1.path=C:\Users\dlcha\AppData\Local\Arduino15\packages\megaTinyCore\tools\python3\3.7.2-post1 -prefs=runtime.tools.arduinoOTA.path=C:\Users\dlcha\AppData\Local\Arduino15\packages\arduino\tools\arduinoOTA\1.3.0 -prefs=runtime.tools.arduinoOTA-1.3.0.path=C:\Users\dlcha\AppData\Local\Arduino15\packages\arduino\tools\arduinoOTA\1.3.0 -prefs=runtime.tools.avrdude.path=C:\Users\dlcha\AppData\Local\Arduino15\packages\DxCore\tools\avrdude\6.3.0-arduino17or18 -prefs=runtime.tools.avrdude-6.3.0-arduino17or18.path=C:\Users\dlcha\AppData\Local\Arduino15\packages\DxCore\tools\avrdude\6.3.0-arduino17or18 -verbose C:\Users\dlcha\Documents\Arduino\ds3231\ds3231.ino
Using board 'atxy4' from platform in folder: C:\Users\dlcha\AppData\Local\Arduino15\packages\megaTinyCore\hardware\megaavr\2.6.10
Using core 'megatinycore' from platform in folder: C:\Users\dlcha\AppData\Local\Arduino15\packages\megaTinyCore\hardware\megaavr\2.6.10
Detecting libraries used...
"C:\\Users\\dlcha\\AppData\\Local\\Arduino15\\packages\\DxCore\\tools\\avr-gcc\\7.3.0-atmel3.6.1-azduino7b1/bin/avr-g++" -c -g -Os -Wall -std=gnu++17 -fpermissive -Wno-sized-deallocation -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -Wno-error=narrowing -flto -w -x c++ -E -CC -mmcu=attiny404 -DF_CPU=20000000L -DCLOCK_SOURCE=0 -DTWI_MORS -DMILLIS_USE_TIMERA0 -DCORE_ATTACH_ALL -DARDUINO=10812 -DARDUINO_AVR_ATtiny404 -DARDUINO_ARCH_MEGAAVR "-DMEGATINYCORE=\"2.6.10\"" -DMEGATINYCORE_MAJOR=2UL -DMEGATINYCORE_MINOR=6UL -DMEGATINYCORE_PATCH=10UL -DMEGATINYCORE_RELEASED=1 -DARDUINO_attinyxy4 "-IC:\\Users\\dlcha\\AppData\\Local\\Arduino15\\packages\\megaTinyCore\\hardware\\megaavr\\2.6.10\\cores\\megatinycore/api/deprecated" "-IC:\\Users\\dlcha\\AppData\\Local\\Arduino15\\packages\\megaTinyCore\\hardware\\megaavr\\2.6.10\\cores\\megatinycore" "-IC:\\Users\\dlcha\\AppData\\Local\\Arduino15\\packages\\megaTinyCore\\hardware\\megaavr\\2.6.10\\variants\\txy4" "C:\\Users\\dlcha\\AppData\\Local\\Temp\\arduino_build_416067\\sketch\\ds3231.ino.cpp" -o nul
Error while detecting libraries included by C:\Users\dlcha\AppData\Local\Temp\arduino_build_416067\sketch\ds3231.ino.cpp
Generating function prototypes...
"C:\\Users\\dlcha\\AppData\\Local\\Arduino15\\packages\\DxCore\\tools\\avr-gcc\\7.3.0-atmel3.6.1-azduino7b1/bin/avr-g++" -c -g -Os -Wall -std=gnu++17 -fpermissive -Wno-sized-deallocation -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -Wno-error=narrowing -flto -w -x c++ -E -CC -mmcu=attiny404 -DF_CPU=20000000L -DCLOCK_SOURCE=0 -DTWI_MORS -DMILLIS_USE_TIMERA0 -DCORE_ATTACH_ALL -DARDUINO=10812 -DARDUINO_AVR_ATtiny404 -DARDUINO_ARCH_MEGAAVR "-DMEGATINYCORE=\"2.6.10\"" -DMEGATINYCORE_MAJOR=2UL -DMEGATINYCORE_MINOR=6UL -DMEGATINYCORE_PATCH=10UL -DMEGATINYCORE_RELEASED=1 -DARDUINO_attinyxy4 "-IC:\\Users\\dlcha\\AppData\\Local\\Arduino15\\packages\\megaTinyCore\\hardware\\megaavr\\2.6.10\\cores\\megatinycore/api/deprecated" "-IC:\\Users\\dlcha\\AppData\\Local\\Arduino15\\packages\\megaTinyCore\\hardware\\megaavr\\2.6.10\\cores\\megatinycore" "-IC:\\Users\\dlcha\\AppData\\Local\\Arduino15\\packages\\megaTinyCore\\hardware\\megaavr\\2.6.10\\variants\\txy4" "C:\\Users\\dlcha\\AppData\\Local\\Temp\\arduino_build_416067\\sketch\\ds3231.ino.cpp" -o "C:\\Users\\dlcha\\AppData\\Local\\Temp\\arduino_build_416067\\preproc\\ctags_target_for_gcc_minus_e.cpp"
avr-g++: error: device-specs/specs-attiny404: No such file or directory

exit status 1
Error compiling for board ATtiny3224/1624/1614/1604/824/814/804/424/414/404/214/204.

[MX682X]

device-specs/specs-attiny404 missing means there is a problem in the compiler files.
The easiest solution I would recomend is to reinstall the core through Arduino. However, Spence's Certificate Renewal is broken, so it won't work. There is a solution that suggest to use https://descartes.net/package_drazzy.com_index.json instead, though.

Or you replace the compiler binary with the version that comes with Microchip studio, but this might lead to more complications as I'm not sure if all flags are supported.