IDE 2 (beta) - problem

Development Tools IDE 2.x
5

Had very little output, but just turned on 'verbose' output, and got this:

Using board 'nano' from platform in folder: C:\Users\johnd\AppData\Local\Arduino15\packages\arduino\hardware\avr\1.8.3
Using core 'arduino' from platform in folder: C:\Users\johnd\AppData\Local\Arduino15\packages\arduino\hardware\avr\1.8.3
Detecting libraries used...
"C:\\Users\\johnd\\AppData\\Local\\Arduino15\\packages\\arduino\\tools\\avr-gcc\\7.3.0-atmel3.6.1-arduino7/bin/avr-g++" -c -g -Os -w -std=gnu++11 -fpermissive -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -Wno-error=narrowing -flto -w -x c++ -E -CC -mmcu=atmega328p -DF_CPU=16000000L -DARDUINO=10607 -DARDUINO_AVR_NANO -DARDUINO_ARCH_AVR "-IC:\\Users\\johnd\\AppData\\Local\\Arduino15\\packages\\arduino\\hardware\\avr\\1.8.3\\cores\\arduino" "-IC:\\Users\\johnd\\AppData\\Local\\Arduino15\\packages\\arduino\\hardware\\avr\\1.8.3\\variants\\eightanaloginputs" "C:\\Users\\johnd\\AppData\\Local\\Temp\\arduino-sketch-E9D74672EDC10F09C71BF9973FC2995C\\sketch\\clock_rtc_only_1.ino.cpp" -o nul
Alternatives for Wire.h: [Wire@1.0]
ResolveLibrary(Wire.h)
  -> candidates: [Wire@1.0]
"C:\\Users\\johnd\\AppData\\Local\\Arduino15\\packages\\arduino\\tools\\avr-gcc\\7.3.0-atmel3.6.1-arduino7/bin/avr-g++" -c -g -Os -w -std=gnu++11 -fpermissive -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -Wno-error=narrowing -flto -w -x c++ -E -CC -mmcu=atmega328p -DF_CPU=16000000L -DARDUINO=10607 -DARDUINO_AVR_NANO -DARDUINO_ARCH_AVR "-IC:\\Users\\johnd\\AppData\\Local\\Arduino15\\packages\\arduino\\hardware\\avr\\1.8.3\\cores\\arduino" "-IC:\\Users\\johnd\\AppData\\Local\\Arduino15\\packages\\arduino\\hardware\\avr\\1.8.3\\variants\\eightanaloginputs" "-IC:\\Users\\johnd\\AppData\\Local\\Arduino15\\packages\\arduino\\hardware\\avr\\1.8.3\\libraries\\Wire\\src" "C:\\Users\\johnd\\AppData\\Local\\Temp\\arduino-sketch-E9D74672EDC10F09C71BF9973FC2995C\\sketch\\clock_rtc_only_1.ino.cpp" -o nul
Alternatives for RtcDS3231.h: []
ResolveLibrary(RtcDS3231.h)
  -> candidates: []
Using library Wire at version 1.0 in folder: C:\Users\johnd\AppData\Local\Arduino15\packages\arduino\hardware\avr\1.8.3\libraries\Wire 
Compilation error: Error: 13 INTERNAL: exit status 1