The command: "execute store result storage <storage> <path> <type> <scale> run attribute <target> <attribute> get" stores a rounded down value in the specified location. 

expected behavior:

the command should store the original value.

This happens even though running the command: "attribute <target> <attribute> get" returns in chat the correct value

commands:

/attribute @n[type=pig] minecraft:safe_fall_distance base set 1.234
/attribute @n[type=pig] minecraft:safe_fall_distance modifier add minecraft:aaa 5.678 add_value
/attribute @n[type=pig] minecraft:safe_fall_distance get
/execute store result storage minecraft:bug test double 1 run attribute @n[type=pig] minecraft:safe_fall_distance get
/data get storage minecraft:bug
/data get entity @n[type=pig] attributes

Also happens with float