Latest Espruino build for Esp8266

I can confirm that the same thing happens when I build it from source using the latest github version when running on an ESP8266-ESP12-F. In my case it loops with this output :

2nd boot version : 1.4(b1)
  SPI Speed      : 80MHz
  SPI Mode       : QIO
  SPI Flash Size & Map: 32Mbit(512KB+512KB)
jump to run user1 @ 1000

r�Invalid saved code in flash!

 ets Jan  8 2013,rst cause:2, boot mode:(3,6)

load 0x40100000, len 1396, room 16 
tail 4
chksum 0x89
load 0x3ffe8000, len 776, room 4 
tail 4
chksum 0xe8
load 0x3ffe8308, len 540, room 4 
tail 8
chksum 0xc0
csum 0xc0

2nd boot version : 1.4(b1)
  SPI Speed      : 80MHz
  SPI Mode       : QIO
... etc.

Any help would be appreciated.