Building in 2021 for SDK 8.4.0

[ssshake]

I just learned of this project and I'm excited to build it and play around with it but the build instructions are not clear.

Where I'm at at this point is the user.cfg by default specifies GCC 4.8.5 but I have no idea where to get that. ESP's documentation links to a much newer version of 8.4.0.

Building against 8.4.0 produces this output. I'm assuming there are just breaking changed between 4 major versions of the SDK.

I could build this with 4.8.5 if only I knew where to find it, google isn't being friendly today.

include/dmastuff.h:11:71: warning: implicit declaration of function 'rom_i2c_writeReg_Mask'; did you mean 'i2c_writeReg_Mask'? [-Wimplicit-function-declaration]
 #define i2c_writeReg_Mask(block, host_id, reg_add, Msb, Lsb, indata)  rom_i2c_writeReg_Mask(block, host_id, reg_add, Msb, Lsb, indata)
                                                                       ^~~~~~~~~~~~~~~~~~~~~
include/dmastuff.h:14:7: note: in expansion of macro 'i2c_writeReg_Mask'
       i2c_writeReg_Mask(block, block##_hostid,  reg_add,  reg_add##_msb,  reg_add##_lsb,  indata)
       ^~~~~~~~~~~~~~~~~
user/ntsc_broadcast.c:348:2: note: in expansion of macro 'i2c_writeReg_Mask_def'
  i2c_writeReg_Mask_def(i2c_bbpll, i2c_bbpll_en_audio_clock_out, 1);
  ^~~~~~~~~~~~~~~~~~~~~
user/3d.c: In function 'tdMultiply':
user/3d.c:187:2: warning: implicit declaration of function 'ets_memcpy' [-Wimplicit-function-declaration]
  ets_memcpy( fout, fotmp, sizeof( fotmp ) );
  ^~~~~~~~~~
user/3d.c:187:2: warning: type of 'ets_memcpy' does not match original declaration [-Wlto-type-mismatch]
  ets_memcpy( fout, fotmp, sizeof( fotmp ) );
  ^
/home/users/rich/esp8266/channel3/esp82xx/toolchain/esp_nonos_sdk/include/osapi.h:41:7: note: return value type mismatch
 void *ets_memcpy(void *dest, const void *src, unsigned int nbyte);
       ^
/home/users/rich/esp8266/channel3/esp82xx/toolchain/esp_nonos_sdk/include/osapi.h:41:7: note: 'ets_memcpy' was previously declared here
/home/users/rich/esp8266/channel3/esp82xx/toolchain/esp_nonos_sdk/include/osapi.h:41:7: note: code may be misoptimized unless -fno-strict-aliasing is used
/home/users/rich/esp8266/channel3/esp82xx/toolchain/esp_nonos_sdk/include/user_interface.h:93:6: warning: type of 'system_os_task' does not match original declaration [-Wlto-type-mismatch]
 bool system_os_task(os_task_t task, uint8 prio, os_event_t *queue, uint8 qlen);