CODECOMPOSER: CCS predefined variables

Part Number: CODECOMPOSER
Other Parts Discussed in Thread: CC1310

Tool/software:

Hi

This may be a stupid question, but.....

i'm using CCS v12.8.1 with TICLANG & sdk8.3 for CC1312 

the one project (rfPacketTx_CC1312R1_LAUNCHXL_tirtos7_ticlang) i downloaded from resource compiler has the following


#if defined(__TI_COMPILER_VERSION__)
#pragma DATA_ALIGN(rxDataEntryBuffer, 4)
static uint8_t
rxDataEntryBuffer[RF_QUEUE_DATA_ENTRY_BUFFER_SIZE(NUM_DATA_ENTRIES,PAYLOAD_LENGTH,NUM_APPENDED_BYTES)];
#elif defined(__GNUC__)
static uint8_t rxDataEntryBuffer[RF_QUEUE_DATA_ENTRY_BUFFER_SIZE(NUM_DATA_ENTRIES,PAYLOAD_LENGTH,NUM_APPENDED_BYTES)] __attribute__((aligned(4)));
#else
#error This compiler is not supported
#endif //defined(__TI_COMPILER_VERSION__)

As it transpires, it appears that __GNUC__ is defined.

My question is:
                  "Where is __GNUC__ defined???"

thanks in advance