https://github.com/monero-project/monero/issues/4695

--- src/cryptonote_basic/miner.cpp.orig	2018-10-09 21:04:07 UTC
+++ src/cryptonote_basic/miner.cpp
@@ -637,7 +637,7 @@ namespace cryptonote
         boost::tribool battery_powered(on_battery_power());
         if(!indeterminate( battery_powered ))
         {
-          on_ac_power = !battery_powered;
+          on_ac_power = bool{!battery_powered};
         }
       }