How to add specific version for the tool chain

It looks I had install the newest version, I need install 2015 q3 version
developer@e4adf3aef62f:~/aws_starter_sdk$ make APP=sample_apps/hello_world
build/toolchains/toolchain_gcc.mk:32: *** " Please use: arm-none-eabi-gcc 2015 q3 version". Stop.

I am a new play, may make simple mistake:
I had remove newest version, and add this one:
developer@e4adf3aef62f:~/aws_starter_sdk$ which arm-none-eabi-gcc
/usr/bin/arm-none-eabi-gcc

but stil fail:
developer@e4adf3aef62f:~/aws_starter_sdk$ make APP=sample_apps/hello_world
build/toolchains/toolchain_gcc.mk:32: *** " Please use: arm-none-eabi-gcc 2015 q3 version". Stop.

Make file:
CROSS_COMPILE := arm-none-eabi-

AS := $(CROSS_COMPILE)gcc
CC := $(CROSS_COMPILE)gcc

compiler-version := $(shell $(CC) -dumpversion)
ifneq ($(compiler-version),4.9.3)
  $(error " Please use: $(CC) 2015 q3 version")

developer@e4adf3aef62f:~/aws_starter_sdk$ arm-none-eabi-gcc -dumpversion
4.8.2

I use the command:

sudo apt-get install arm-none-eabi-gcc
How to tell server I need 4.9.3?

But when I try to remove, it complain cannot find the package.
I use apt-cache search arm-none to remove it one by one

I try to install new version, now it cannot find the package
developer@e4adf3aef62f:~/aws_starter_sdk$ sudo apt-get install arm-none-eabi-gcc=4.9-2015-q3-update
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to locate package arm-none-eabi-gcc

developer@e4adf3aef62f:~/aws_starter_sdk$ ls /etc/apt/sources.list.d/
git-core-ppa-trusty.list team-gcc-arm-embedded-ppa-trusty.list
git-core-ppa-trusty.list.save team-gcc-arm-embedded-ppa-trusty.list.save
guo-gcc-arm-embedded-saucy.list terry_guo-gcc-arm-embedded-saucy.list
ros-latest.list terry_guo-gcc-arm-embedded-saucy.list.save
ros-latest.list.save

Could the package is not remove success, Should I remove those one by one:
developer@e4adf3aef62f:/etc/apt/sources.list.d$ apt-cache policy gcc-arm-embedded
gcc-arm-embedded:
  Installed: (none)
  Candidate: 5-2015q4-1~trusty1
  Version table:
     5-2015q4-1~trusty1 0
        500 http://ppa.launchpad.net/team-gcc-arm-embedded/ppa/ubuntu/ trusty/main amd64 Packages
developer@e4adf3aef62f:/etc/apt/sources.list.d$ apt-cache search gcc-arm
gcc-arm-linux-gnueabihf - The GNU C compiler for armhf architecture
gcc-arm-linux-androideabi - cross toolchain and binutils for Android/Bionic on ARM
gcc-arm-linux-gnueabi - The GNU C compiler for armel architecture
gcc-arm-none-eabi - GCC cross compiler for ARM Cortex-A/R/M processors

Last question:
  I think the complier is backward compatible, right?
  So I modify the make file, and only install the newest version.
Thanks
John

It works. Thanks

how do you modify the make file?