Okay, so I got a load of missing packages from http://www.bitshrine.org/gpp/, copied them to my /opt/freescale/pkgs directory and ran the command like you said and it demands that I enter a "Platform choice". There is no option for the i.MX6. What do I do?
Here are the options it gives me:
Future Designs, Inc. ARM9DIMM-LPC3250 board
senTec COBRA5475 Coldfire/M68k (MMU)
Embedded Artists 3131 board with the NXP LPC313X SoC
Embedded Artists 3152 board with the NXP LPC3152 SoC
Embedded Artists LPC3250 OEM Board with the NXP LPC32XX SoC
EP93xx development board
Freescale IMX21 ADS reference board
Freescale IMX27 ADS reference board
Freescale IMX31 ADS reference board
Logic PD LPD7A404 board
Freescale M5208EVB Coldfire/M68k (noMMU)
Freescale M5253EVB Coldfire/M68k (noMMU)
Freescale M532xEVB Coldfire/M68k (noMMU)
Freescale M537xEVB Coldfire (noMMU)
Freescale M5445X Coldfire/M68k (MMU)
Freescale MCF547x_8x Coldfire/M68k (MMU)
Freescale MPC512x based boards
Freescale MPC5200 based development boards
Freescale MPC7448HPCII PPC development board
Freescale MPC82xx based development boards
Freescale MPC8349EA MDS PowerPC board
Freescale MPC8349E-mITX board
Freescale MPC8360E PB PowerPC board
Freescale MPC837xE MDS development board
Freescale MPC8536DS PowerPC development board
Freescale MPC8548CDS PPC development board
Freescale MPC8555CDS and MPC8541CDS PPC development board
Freescale MPC8560ADS PQ3 PowerPC board
Freescale MPC860FADS
Freescale MPC8641DHPCN PPC development board
Phytec 3250 board with the NXP LPC32XX SoC
A&MLtd Adder MPC875 PowerPC board
Raspberry Pi with BCM2835 SoC
TQ Components TQM823L PowerPC board