I-CUBE-LRWAN v2.0.0 with B-L072Z-LRWAN1 ?

The warning that 'fBuffer' may be used uninitialized seems to be from GCC inlining 'static' functions - as the warning is reported in PrepareFrame(), but the definition of fBuffer is in LoRaMacMcpsRequest()

PrepareFrame() is called by Send() which is called from LoRaMacMcpsRequest():

LoRaMacStatus_t LoRaMacMcpsRequest( McpsReq_t* mcpsRequest, bool allowDelayedTx )
{
 GetPhyParams_t getPhy;
 PhyParam_t phyParam;
 LoRaMacStatus_t status = LORAMAC_STATUS_SERVICE_UNKNOWN;
 LoRaMacHeader_t macHdr;
 VerifyParams_t verify;
 uint8_t fPort = 0;
 void* fBuffer; // <=== *** Defined here
 uint16_t fBufferSize;
 int8_t datarate = DR_0;
 bool readyToSend = false;
 
 if( mcpsRequest == NULL )
 {
 return LORAMAC_STATUS_PARAMETER_INVALID;
 }
 if( LoRaMacIsBusy( ) == true )
 {
 return LORAMAC_STATUS_BUSY;
 }
 
 macHdr.Value = 0;
 memset1( ( uint8_t* ) &MacCtx.McpsConfirm, 0, sizeof( MacCtx.McpsConfirm ) );
 MacCtx.McpsConfirm.Status = LORAMAC_EVENT_INFO_STATUS_ERROR;
 
 // AckTimeoutRetriesCounter must be reset every time a new request (unconfirmed or confirmed) is performed.
 MacCtx.AckTimeoutRetriesCounter = 1;
 
 switch( mcpsRequest->Type )
 {
 case MCPS_UNCONFIRMED:
 {
 readyToSend = true;
 MacCtx.AckTimeoutRetries = 1;
 
 macHdr.Bits.MType = FRAME_TYPE_DATA_UNCONFIRMED_UP;
 fPort = mcpsRequest->Req.Unconfirmed.fPort;
 fBuffer = mcpsRequest->Req.Unconfirmed.fBuffer;
 fBufferSize = mcpsRequest->Req.Unconfirmed.fBufferSize;
 datarate = mcpsRequest->Req.Unconfirmed.Datarate;
 break;
 }
 case MCPS_CONFIRMED:
 {
 readyToSend = true;
 MacCtx.AckTimeoutRetries = MIN( mcpsRequest->Req.Confirmed.NbTrials, MAX_ACK_RETRIES );
 
 macHdr.Bits.MType = FRAME_TYPE_DATA_CONFIRMED_UP;
 fPort = mcpsRequest->Req.Confirmed.fPort;
 fBuffer = mcpsRequest->Req.Confirmed.fBuffer;
 fBufferSize = mcpsRequest->Req.Confirmed.fBufferSize;
 datarate = mcpsRequest->Req.Confirmed.Datarate;
 break;
 }
 case MCPS_PROPRIETARY:
 {
 readyToSend = true;
 MacCtx.AckTimeoutRetries = 1;
 
 macHdr.Bits.MType = FRAME_TYPE_PROPRIETARY;
 fBuffer = mcpsRequest->Req.Proprietary.fBuffer;
 fBufferSize = mcpsRequest->Req.Proprietary.fBufferSize;
 datarate = mcpsRequest->Req.Proprietary.Datarate;
 break;
 }
 default: // <=== *** this potentially leaves fBuffer uninitialised
 break;
 }
 
 // Get the minimum possible datarate
 getPhy.Attribute = PHY_MIN_TX_DR;
 getPhy.UplinkDwellTime = MacCtx.NvmCtx->MacParams.UplinkDwellTime;
 phyParam = RegionGetPhyParam( MacCtx.NvmCtx->Region, &getPhy );
 // Apply the minimum possible datarate.
 // Some regions have limitations for the minimum datarate.
 datarate = MAX( datarate, ( int8_t )phyParam.Value );
 
 if( readyToSend == true )
 {
 if( MacCtx.NvmCtx->AdrCtrlOn == false )
 {
 verify.DatarateParams.Datarate = datarate;
 verify.DatarateParams.UplinkDwellTime = MacCtx.NvmCtx->MacParams.UplinkDwellTime;
 
 if( RegionVerify( MacCtx.NvmCtx->Region, &verify, PHY_TX_DR ) == true )
 {
 MacCtx.NvmCtx->MacParams.ChannelsDatarate = verify.DatarateParams.Datarate;
 }
 else
 {
 return LORAMAC_STATUS_PARAMETER_INVALID;
 }
 }
 
 status = Send( &macHdr, fPort, fBuffer, fBufferSize, allowDelayedTx ); // <=== *** used here