Rebuilding Fusion drive will NOT erase the hdd?

My ssd from selfmade fusionDrive in my cMP died. After booting to recovery mode and opening Disk Utility, It shows my fusiondrive in red. Then it says "The Fusion Drive is missing a disk" AND after "Rebuilding will erase the following disks:" and then the white box is empty?!?

Does this mean, that it won't erase the content in hdd?

Or is it just not able to see the name of the volume, since ssd is...

Rebuilding Fusion drive will NOT erase the hdd?