diff --git a/MdeModulePkg/Bus/Ata/AhciPei/AhciMode.c b/MdeModulePkg/Bus/Ata/AhciPei/AhciMode.c
index 0f0198d308..92fb30638e 100644
--- a/MdeModulePkg/Bus/Ata/AhciPei/AhciMode.c
+++ b/MdeModulePkg/Bus/Ata/AhciPei/AhciMode.c
@@ -759,7 +759,7 @@ AhciPioTransfer (
       DEBUG_ERROR,
       "%a: Driver only support a maximum of 0x%x PRDT entries, "
       "current number of data byte 0x%x is too large, maximum allowed is 0x%x.\n",
-      __FUNCTION__,
+      __func__,
       AHCI_MAX_PRDT_NUMBER,
       DataCount,
       AHCI_MAX_PRDT_NUMBER * AHCI_MAX_DATA_PER_PRDT
@@ -778,7 +778,7 @@ AhciPioTransfer (
                 &MapData
                 );
   if (EFI_ERROR (Status) || (MapLength != DataCount)) {
-    DEBUG ((DEBUG_ERROR, "%a: Fail to map data buffer.\n", __FUNCTION__));
+    DEBUG ((DEBUG_ERROR, "%a: Fail to map data buffer.\n", __func__));
     return EFI_OUT_OF_RESOURCES;
   }
 
@@ -860,7 +860,7 @@ AhciPioTransfer (
       Offset         = FisBaseAddr + AHCI_PIO_FIS_OFFSET;
       Status         = AhciCheckMemSet (Offset, AHCI_FIS_TYPE_MASK, AHCI_FIS_PIO_SETUP);
       if (!EFI_ERROR (Status)) {
-        DEBUG ((DEBUG_INFO, "%a: PioFisReceived.\n", __FUNCTION__));
+        DEBUG ((DEBUG_INFO, "%a: PioFisReceived.\n", __func__));
         PioFisReceived = TRUE;
       }
 
@@ -874,7 +874,7 @@ AhciPioTransfer (
       Offset = FisBaseAddr + AHCI_D2H_FIS_OFFSET;
       Status = AhciCheckMemSet (Offset, AHCI_FIS_TYPE_MASK, AHCI_FIS_REGISTER_D2H);
       if (!EFI_ERROR (Status)) {
-        DEBUG ((DEBUG_INFO, "%a: D2hFisReceived.\n", __FUNCTION__));
+        DEBUG ((DEBUG_INFO, "%a: D2hFisReceived.\n", __func__));
         D2hFisReceived = TRUE;
       }
 
@@ -918,7 +918,7 @@ AhciPioTransfer (
                Timeout
                );
     if (EFI_ERROR (Status)) {
-      DEBUG ((DEBUG_ERROR, "%a: AhciWaitMemSet (%r)\n", __FUNCTION__, Status));
+      DEBUG ((DEBUG_ERROR, "%a: AhciWaitMemSet (%r)\n", __func__, Status));
       goto Exit;
     }
 
@@ -1479,7 +1479,7 @@ IdentifyAtaDevice (
     DEBUG ((
       DEBUG_ERROR,
       "%a: Not a hard disk device on Port 0x%x PortMultiplierPort 0x%x\n",
-      __FUNCTION__,
+      __func__,
       DeviceData->Port,
       DeviceData->PortMultiplier
       ));
@@ -1489,7 +1489,7 @@ IdentifyAtaDevice (
   DEBUG ((
     DEBUG_INFO,
     "%a: Identify Device: Port 0x%x PortMultiplierPort 0x%x\n",
-    __FUNCTION__,
+    __func__,
     DeviceData->Port,
     DeviceData->PortMultiplier
     ));
@@ -1518,7 +1518,7 @@ IdentifyAtaDevice (
   }
 
   if (Capacity == 0) {
-    DEBUG ((DEBUG_ERROR, "%a: Invalid Capacity (0) for ATA device.\n", __FUNCTION__));
+    DEBUG ((DEBUG_ERROR, "%a: Invalid Capacity (0) for ATA device.\n", __func__));
     return EFI_UNSUPPORTED;
   }
 
@@ -1532,7 +1532,7 @@ IdentifyAtaDevice (
   DEBUG ((
     DEBUG_INFO,
     "%a: PhyLogicSectorSupport = 0x%x\n",
-    __FUNCTION__,
+    __func__,
     PhyLogicSectorSupport
     ));
   if ((PhyLogicSectorSupport & (BIT14 | BIT15)) == BIT14) {
@@ -1550,20 +1550,20 @@ IdentifyAtaDevice (
   //
   MaxSectorCount = mMaxTransferBlockNumber[DeviceData->Lba48Bit];
   if ((Media->BlockSize == 0) || (Media->BlockSize > MAX_UINT32 / MaxSectorCount)) {
-    DEBUG ((DEBUG_ERROR, "%a: Invalid BlockSize (0x%x).\n", __FUNCTION__, Media->BlockSize));
+    DEBUG ((DEBUG_ERROR, "%a: Invalid BlockSize (0x%x).\n", __func__, Media->BlockSize));
     return EFI_UNSUPPORTED;
   }
 
   DEBUG ((
     DEBUG_INFO,
     "%a: BlockSize = 0x%x, LastBlock = 0x%lx\n",
-    __FUNCTION__,
+    __func__,
     Media->BlockSize,
     Media->LastBlock
     ));
 
   if ((IdentifyData->trusted_computing_support & BIT0) != 0) {
-    DEBUG ((DEBUG_INFO, "%a: Found Trust Computing feature support.\n", __FUNCTION__));
+    DEBUG ((DEBUG_INFO, "%a: Found Trust Computing feature support.\n", __func__));
     DeviceData->TrustComputing = TRUE;
   }
 
@@ -1686,7 +1686,7 @@ AhciModeInitialization (
 
   Status = AhciReset (AhciBar, AHCI_PEI_RESET_TIMEOUT);
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a: AHCI HBA reset failed with %r.\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "%a: AHCI HBA reset failed with %r.\n", __func__, Status));
     return EFI_DEVICE_ERROR;
   }
 
@@ -1708,7 +1708,7 @@ AhciModeInitialization (
     DEBUG ((
       DEBUG_ERROR,
       "%a: Transfer-related data allocation failed with %r.\n",
-      __FUNCTION__,
+      __func__,
       Status
       ));
     return EFI_OUT_OF_RESOURCES;
@@ -1814,7 +1814,7 @@ AhciModeInitialization (
         //
         Offset = AHCI_PORT_START + Port * AHCI_PORT_REG_WIDTH + AHCI_PORT_CMD;
         AhciAndReg (AhciBar, Offset, (UINT32) ~(AHCI_PORT_CMD_SUD));
-        DEBUG ((DEBUG_ERROR, "%a: No device detected at Port %d.\n", __FUNCTION__, Port));
+        DEBUG ((DEBUG_ERROR, "%a: No device detected at Port %d.\n", __func__, Port));
         continue;
       }
 
@@ -1844,7 +1844,7 @@ AhciModeInitialization (
         DEBUG ((
           DEBUG_ERROR,
           "%a: Port %d device presence detected but phy not ready (TFD=0x%x).\n",
-          __FUNCTION__,
+          __func__,
           Port,
           Data
           ));
@@ -1866,7 +1866,7 @@ AhciModeInitialization (
         DEBUG ((
           DEBUG_ERROR,
           "%a: Error occurred when waiting for the first D2H register FIS - %r\n",
-          __FUNCTION__,
+          __func__,
           Status
           ));
         continue;
@@ -1876,11 +1876,11 @@ AhciModeInitialization (
       if ((Data & AHCI_ATAPI_SIG_MASK) == AHCI_ATA_DEVICE_SIG) {
         Status = AhciIdentify (Private, Port, 0, PortIndex - 1, &IdentifyData);
         if (EFI_ERROR (Status)) {
-          DEBUG ((DEBUG_ERROR, "%a: AhciIdentify() failed with %r\n", __FUNCTION__, Status));
+          DEBUG ((DEBUG_ERROR, "%a: AhciIdentify() failed with %r\n", __func__, Status));
           continue;
         }
 
-        DEBUG ((DEBUG_INFO, "%a: ATA hard disk found on Port %d.\n", __FUNCTION__, Port));
+        DEBUG ((DEBUG_INFO, "%a: ATA hard disk found on Port %d.\n", __func__, Port));
       } else {
         continue;
       }
diff --git a/MdeModulePkg/Bus/Ata/AhciPei/AhciPei.c b/MdeModulePkg/Bus/Ata/AhciPei/AhciPei.c
index e33d863d2a..7ea36afa25 100644
--- a/MdeModulePkg/Bus/Ata/AhciPei/AhciPei.c
+++ b/MdeModulePkg/Bus/Ata/AhciPei/AhciPei.c
@@ -156,7 +156,7 @@ AtaAhciInitPrivateData (
   //
   Status = PeiServicesGetBootMode (&BootMode);
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a: Fail to get the current boot mode.\n", __FUNCTION__));
+    DEBUG ((DEBUG_ERROR, "%a: Fail to get the current boot mode.\n", __func__));
     return Status;
   }
 
@@ -168,7 +168,7 @@ AtaAhciInitPrivateData (
     DEBUG ((
       DEBUG_ERROR,
       "%a: The device path is invalid.\n",
-      __FUNCTION__
+      __func__
       ));
     return Status;
   }
@@ -196,7 +196,7 @@ AtaAhciInitPrivateData (
     DEBUG ((
       DEBUG_ERROR,
       "%a: Fail to allocate private data.\n",
-      __FUNCTION__
+      __func__
       ));
     return EFI_OUT_OF_RESOURCES;
   }
@@ -260,7 +260,7 @@ AtaAhciInitPrivateData (
     DEBUG ((
       DEBUG_INFO,
       "%a: Security Security Command PPI will be produced.\n",
-      __FUNCTION__
+      __func__
       ));
     Private->StorageSecurityPpi.Revision           = EDKII_STORAGE_SECURITY_PPI_REVISION;
     Private->StorageSecurityPpi.GetNumberofDevices = AhciStorageSecurityGetDeviceNo;
@@ -329,7 +329,7 @@ AtaAhciInitPrivateDataFromHostControllerPpi (
       DEBUG ((
         DEBUG_ERROR,
         "%a: Fail to allocate get the device path for Controller %d.\n",
-        __FUNCTION__,
+        __func__,
         Controller
         ));
       return Status;
@@ -340,7 +340,7 @@ AtaAhciInitPrivateDataFromHostControllerPpi (
       DEBUG ((
         DEBUG_ERROR,
         "%a: Controller initialization fail for Controller %d with Status - %r.\n",
-        __FUNCTION__,
+        __func__,
         Controller,
         Status
         ));
@@ -348,7 +348,7 @@ AtaAhciInitPrivateDataFromHostControllerPpi (
       DEBUG ((
         DEBUG_INFO,
         "%a: Controller %d has been successfully initialized.\n",
-        __FUNCTION__,
+        __func__,
         Controller
         ));
     }
@@ -471,7 +471,7 @@ AtaAhciInitPrivateDataFromPciDevice (
     DEBUG ((
       DEBUG_INFO,
       "%a: Failed to init controller, with Status - %r\n",
-      __FUNCTION__,
+      __func__,
       Status
       ));
   }
@@ -522,7 +522,7 @@ AtaAhciPeimEntry (
   IN CONST EFI_PEI_SERVICES  **PeiServices
   )
 {
-  DEBUG ((DEBUG_INFO, "%a: Enters.\n", __FUNCTION__));
+  DEBUG ((DEBUG_INFO, "%a: Enters.\n", __func__));
 
   PeiServicesNotifyPpi (&mAtaAhciHostControllerNotify);
 
diff --git a/MdeModulePkg/Bus/Ata/AhciPei/AhciPeiBlockIo.c b/MdeModulePkg/Bus/Ata/AhciPei/AhciPeiBlockIo.c
index c5d1f3fffb..5eb2a9ce82 100644
--- a/MdeModulePkg/Bus/Ata/AhciPei/AhciPeiBlockIo.c
+++ b/MdeModulePkg/Bus/Ata/AhciPei/AhciPeiBlockIo.c
@@ -101,7 +101,7 @@ AccessAtaDevice (
     DEBUG ((
       DEBUG_BLKIO,
       "%a: Blocking AccessAtaDevice, TransferBlockNumber = %x; StartLba = %x\n",
-      __FUNCTION__,
+      __func__,
       TransferBlockNumber,
       StartLba
       ));
diff --git a/MdeModulePkg/Bus/Pci/EhciDxe/Ehci.c b/MdeModulePkg/Bus/Pci/EhciDxe/Ehci.c
index e903593b01..b4f1a50799 100644
--- a/MdeModulePkg/Bus/Pci/EhciDxe/Ehci.c
+++ b/MdeModulePkg/Bus/Pci/EhciDxe/Ehci.c
@@ -1863,7 +1863,7 @@ EhcDriverBindingStart (
       DEBUG ((
         DEBUG_WARN,
         "%a: failed to enable 64-bit DMA on 64-bit capable controller @ %p (%r)\n",
-        __FUNCTION__,
+        __func__,
         Controller,
         Status
         ));
diff --git a/MdeModulePkg/Bus/Pci/EhciDxe/EhciSched.c b/MdeModulePkg/Bus/Pci/EhciDxe/EhciSched.c
index 6967aabceb..59bbe9fc23 100644
--- a/MdeModulePkg/Bus/Pci/EhciDxe/EhciSched.c
+++ b/MdeModulePkg/Bus/Pci/EhciDxe/EhciSched.c
@@ -836,7 +836,7 @@ EhciInsertAsyncIntTransfer (
   Data = AllocatePool (DataLen);
 
   if (Data == NULL) {
-    DEBUG ((DEBUG_ERROR, "%a: failed to allocate buffer\n", __FUNCTION__));
+    DEBUG ((DEBUG_ERROR, "%a: failed to allocate buffer\n", __func__));
     return NULL;
   }
 
@@ -858,7 +858,7 @@ EhciInsertAsyncIntTransfer (
           );
 
   if (Urb == NULL) {
-    DEBUG ((DEBUG_ERROR, "%a: failed to create URB\n", __FUNCTION__));
+    DEBUG ((DEBUG_ERROR, "%a: failed to create URB\n", __func__));
     gBS->FreePool (Data);
     return NULL;
   }
diff --git a/MdeModulePkg/Bus/Pci/NonDiscoverablePciDeviceDxe/NonDiscoverablePciDeviceIo.c b/MdeModulePkg/Bus/Pci/NonDiscoverablePciDeviceDxe/NonDiscoverablePciDeviceIo.c
index 2fb78d8f96..e31c38deed 100644
--- a/MdeModulePkg/Bus/Pci/NonDiscoverablePciDeviceDxe/NonDiscoverablePciDeviceIo.c
+++ b/MdeModulePkg/Bus/Pci/NonDiscoverablePciDeviceDxe/NonDiscoverablePciDeviceIo.c
@@ -1843,7 +1843,7 @@ InitializePciIoProtocol (
       DEBUG ((
         DEBUG_ERROR,
         "%a: resource count exceeds number of emulated BARs\n",
-        __FUNCTION__
+        __func__
         ));
       ASSERT (FALSE);
       break;
diff --git a/MdeModulePkg/Bus/Pci/NvmExpressDxe/NvmExpressBlockIo.c b/MdeModulePkg/Bus/Pci/NvmExpressDxe/NvmExpressBlockIo.c
index b33c903412..b6ed7f7031 100644
--- a/MdeModulePkg/Bus/Pci/NvmExpressDxe/NvmExpressBlockIo.c
+++ b/MdeModulePkg/Bus/Pci/NvmExpressDxe/NvmExpressBlockIo.c
@@ -216,7 +216,7 @@ NvmeRead (
     DEBUG_BLKIO,
     "%a: Lba = 0x%08Lx, Original = 0x%08Lx, "
     "Remaining = 0x%08Lx, BlockSize = 0x%x, Status = %r\n",
-    __FUNCTION__,
+    __func__,
     Lba,
     (UINT64)OrginalBlocks,
     (UINT64)Blocks,
@@ -302,7 +302,7 @@ NvmeWrite (
     DEBUG_BLKIO,
     "%a: Lba = 0x%08Lx, Original = 0x%08Lx, "
     "Remaining = 0x%08Lx, BlockSize = 0x%x, Status = %r\n",
-    __FUNCTION__,
+    __func__,
     Lba,
     (UINT64)OrginalBlocks,
     (UINT64)Blocks,
@@ -817,7 +817,7 @@ NvmeAsyncRead (
     DEBUG_BLKIO,
     "%a: Lba = 0x%08Lx, Original = 0x%08Lx, "
     "Remaining = 0x%08Lx, BlockSize = 0x%x, Status = %r\n",
-    __FUNCTION__,
+    __func__,
     Lba,
     (UINT64)OrginalBlocks,
     (UINT64)Blocks,
@@ -945,7 +945,7 @@ NvmeAsyncWrite (
     DEBUG_BLKIO,
     "%a: Lba = 0x%08Lx, Original = 0x%08Lx, "
     "Remaining = 0x%08Lx, BlockSize = 0x%x, Status = %r\n",
-    __FUNCTION__,
+    __func__,
     Lba,
     (UINT64)OrginalBlocks,
     (UINT64)Blocks,
diff --git a/MdeModulePkg/Bus/Pci/NvmExpressPei/NvmExpressPei.c b/MdeModulePkg/Bus/Pci/NvmExpressPei/NvmExpressPei.c
index 3e6f75345d..38f86487e2 100644
--- a/MdeModulePkg/Bus/Pci/NvmExpressPei/NvmExpressPei.c
+++ b/MdeModulePkg/Bus/Pci/NvmExpressPei/NvmExpressPei.c
@@ -91,7 +91,7 @@ EnumerateNvmeDevNamespace (
              NamespaceData
              );
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a: NvmeIdentifyNamespace fail, Status - %r\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "%a: NvmeIdentifyNamespace fail, Status - %r\n", __func__, Status));
     goto Exit;
   }
 
@@ -99,7 +99,7 @@ EnumerateNvmeDevNamespace (
   // Validate Namespace
   //
   if (NamespaceData->Ncap == 0) {
-    DEBUG ((DEBUG_INFO, "%a: Namespace ID %d is an inactive one.\n", __FUNCTION__, NamespaceId));
+    DEBUG ((DEBUG_INFO, "%a: Namespace ID %d is an inactive one.\n", __func__, NamespaceId));
     Status = EFI_DEVICE_ERROR;
     goto Exit;
   }
@@ -142,7 +142,7 @@ EnumerateNvmeDevNamespace (
   DEBUG ((
     DEBUG_INFO,
     "%a: Namespace ID %d - BlockSize = 0x%x, LastBlock = 0x%lx\n",
-    __FUNCTION__,
+    __func__,
     NamespaceId,
     NamespaceInfo->Media.BlockSize,
     NamespaceInfo->Media.LastBlock
@@ -246,14 +246,14 @@ NvmeInitPrivateData (
   PEI_NVME_CONTROLLER_PRIVATE_DATA  *Private;
   EFI_PHYSICAL_ADDRESS              DeviceAddress;
 
-  DEBUG ((DEBUG_INFO, "%a: Enters.\n", __FUNCTION__));
+  DEBUG ((DEBUG_INFO, "%a: Enters.\n", __func__));
 
   //
   // Get the current boot mode.
   //
   Status = PeiServicesGetBootMode (&BootMode);
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a: Fail to get the current boot mode.\n", __FUNCTION__));
+    DEBUG ((DEBUG_ERROR, "%a: Fail to get the current boot mode.\n", __func__));
     return Status;
   }
 
@@ -265,7 +265,7 @@ NvmeInitPrivateData (
     DEBUG ((
       DEBUG_ERROR,
       "%a: The device path is invalid.\n",
-      __FUNCTION__
+      __func__
       ));
     return Status;
   }
@@ -282,7 +282,7 @@ NvmeInitPrivateData (
     DEBUG ((
       DEBUG_ERROR,
       "%a: skipped during S3.\n",
-      __FUNCTION__
+      __func__
       ));
     return EFI_SUCCESS;
   }
@@ -295,7 +295,7 @@ NvmeInitPrivateData (
     DEBUG ((
       DEBUG_ERROR,
       "%a: Fail to allocate private data.\n",
-      __FUNCTION__
+      __func__
       ));
     return EFI_OUT_OF_RESOURCES;
   }
@@ -313,13 +313,13 @@ NvmeInitPrivateData (
     DEBUG ((
       DEBUG_ERROR,
       "%a: Fail to allocate DMA buffers.\n",
-      __FUNCTION__
+      __func__
       ));
     return Status;
   }
 
   ASSERT (DeviceAddress == ((EFI_PHYSICAL_ADDRESS)(UINTN)Private->Buffer));
-  DEBUG ((DEBUG_INFO, "%a: DMA buffer base at 0x%x\n", __FUNCTION__, Private->Buffer));
+  DEBUG ((DEBUG_INFO, "%a: DMA buffer base at 0x%x\n", __func__, Private->Buffer));
 
   //
   // Initialize controller private data
@@ -337,7 +337,7 @@ NvmeInitPrivateData (
     DEBUG ((
       DEBUG_ERROR,
       "%a: Controller initialization fail with Status - %r.\n",
-      __FUNCTION__,
+      __func__,
       Status
       ));
     NvmeFreeDmaResource (Private);
@@ -355,7 +355,7 @@ NvmeInitPrivateData (
     DEBUG ((
       DEBUG_ERROR,
       "%a: Namespaces discovery fail with Status - %r.\n",
-      __FUNCTION__,
+      __func__,
       Status
       ));
     NvmeFreeDmaResource (Private);
@@ -414,7 +414,7 @@ NvmeInitPrivateData (
     DEBUG ((
       DEBUG_INFO,
       "%a: Security Security Command PPI will be produced.\n",
-      __FUNCTION__
+      __func__
       ));
     Private->StorageSecurityPpi.Revision           = EDKII_STORAGE_SECURITY_PPI_REVISION;
     Private->StorageSecurityPpi.GetNumberofDevices = NvmeStorageSecurityGetDeviceNo;
@@ -557,7 +557,7 @@ NvmeInitControllerDataFromPciDevice (
     DEBUG ((
       DEBUG_INFO,
       "%a: Failed to init controller, with Status - %r\n",
-      __FUNCTION__,
+      __func__,
       Status
       ));
   }
@@ -635,7 +635,7 @@ NvmeInitControllerFromHostControllerPpi (
       DEBUG ((
         DEBUG_ERROR,
         "%a: Fail to allocate get the device path for Controller %d.\n",
-        __FUNCTION__,
+        __func__,
         Controller
         ));
       return Status;
@@ -646,7 +646,7 @@ NvmeInitControllerFromHostControllerPpi (
       DEBUG ((
         DEBUG_ERROR,
         "%a: Controller initialization fail for Controller %d with Status - %r.\n",
-        __FUNCTION__,
+        __func__,
         Controller,
         Status
         ));
@@ -654,7 +654,7 @@ NvmeInitControllerFromHostControllerPpi (
       DEBUG ((
         DEBUG_INFO,
         "%a: Controller %d has been successfully initialized.\n",
-        __FUNCTION__,
+        __func__,
         Controller
         ));
     }
@@ -712,7 +712,7 @@ NvmExpressPeimEntry (
   IN CONST EFI_PEI_SERVICES  **PeiServices
   )
 {
-  DEBUG ((DEBUG_INFO, "%a: Enters.\n", __FUNCTION__));
+  DEBUG ((DEBUG_INFO, "%a: Enters.\n", __func__));
 
   PeiServicesNotifyPpi (&mNvmeHostControllerNotify);
 
diff --git a/MdeModulePkg/Bus/Pci/NvmExpressPei/NvmExpressPeiBlockIo.c b/MdeModulePkg/Bus/Pci/NvmExpressPei/NvmExpressPeiBlockIo.c
index 576481dcee..a61238086c 100644
--- a/MdeModulePkg/Bus/Pci/NvmExpressPei/NvmExpressPeiBlockIo.c
+++ b/MdeModulePkg/Bus/Pci/NvmExpressPei/NvmExpressPeiBlockIo.c
@@ -125,14 +125,14 @@ NvmeRead (
       MaxTransferBlocks = MaxTransferBlocks >> 1;
 
       if ((Retries > NVME_READ_MAX_RETRY) || (MaxTransferBlocks < 1)) {
-        DEBUG ((DEBUG_ERROR, "%a: ReadSectors fail, Status - %r\n", __FUNCTION__, Status));
+        DEBUG ((DEBUG_ERROR, "%a: ReadSectors fail, Status - %r\n", __func__, Status));
         break;
       }
 
       DEBUG ((
         DEBUG_BLKIO,
         "%a: ReadSectors fail, retry with smaller transfer block number - 0x%x\n",
-        __FUNCTION__,
+        __func__,
         MaxTransferBlocks
         ));
       continue;
@@ -151,7 +151,7 @@ NvmeRead (
     DEBUG_BLKIO,
     "%a: Lba = 0x%08Lx, Original = 0x%08Lx, "
     "Remaining = 0x%08Lx, BlockSize = 0x%x, Status = %r\n",
-    __FUNCTION__,
+    __func__,
     Lba,
     (UINT64)OrginalBlocks,
     (UINT64)Blocks,
diff --git a/MdeModulePkg/Bus/Pci/NvmExpressPei/NvmExpressPeiHci.c b/MdeModulePkg/Bus/Pci/NvmExpressPei/NvmExpressPeiHci.c
index bff5cfd0d5..fc7b684940 100644
--- a/MdeModulePkg/Bus/Pci/NvmExpressPei/NvmExpressPeiHci.c
+++ b/MdeModulePkg/Bus/Pci/NvmExpressPei/NvmExpressPeiHci.c
@@ -138,7 +138,7 @@ NvmeBaseMemPageOffset (
   PageSizeList[4] = NVME_PRP_SIZE; /* PRPs */
 
   if (BaseMemIndex > MAX_BASEMEM_COUNT) {
-    DEBUG ((DEBUG_ERROR, "%a: The input BaseMem index is invalid.\n", __FUNCTION__));
+    DEBUG ((DEBUG_ERROR, "%a: The input BaseMem index is invalid.\n", __func__));
     ASSERT (FALSE);
     return 0;
   }
@@ -191,7 +191,7 @@ NvmeWaitController (
     //
     Status = NVME_GET_CSTS (Private, &Csts);
     if (EFI_ERROR (Status)) {
-      DEBUG ((DEBUG_ERROR, "%a: NVME_GET_CSTS fail, Status - %r\n", __FUNCTION__, Status));
+      DEBUG ((DEBUG_ERROR, "%a: NVME_GET_CSTS fail, Status - %r\n", __func__, Status));
       return Status;
     }
 
@@ -232,7 +232,7 @@ NvmeDisableController (
   //
   Status = NVME_GET_CC (Private, &Cc);
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a: NVME_GET_CC fail, Status - %r\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "%a: NVME_GET_CC fail, Status - %r\n", __func__, Status));
     goto ErrorExit;
   }
 
@@ -243,21 +243,21 @@ NvmeDisableController (
     //
     Status = NVME_SET_CC (Private, &Cc);
     if (EFI_ERROR (Status)) {
-      DEBUG ((DEBUG_ERROR, "%a: NVME_SET_CC fail, Status - %r\n", __FUNCTION__, Status));
+      DEBUG ((DEBUG_ERROR, "%a: NVME_SET_CC fail, Status - %r\n", __func__, Status));
       goto ErrorExit;
     }
   }
 
   Status = NvmeWaitController (Private, FALSE);
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a: NvmeWaitController fail, Status - %r\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "%a: NvmeWaitController fail, Status - %r\n", __func__, Status));
     goto ErrorExit;
   }
 
   return EFI_SUCCESS;
 
 ErrorExit:
-  DEBUG ((DEBUG_ERROR, "%a fail, Status - %r\n", __FUNCTION__, Status));
+  DEBUG ((DEBUG_ERROR, "%a fail, Status - %r\n", __func__, Status));
   return Status;
 }
 
@@ -289,20 +289,20 @@ NvmeEnableController (
   Cc.Iocqes = 4;
   Status    = NVME_SET_CC (Private, &Cc);
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a: NVME_SET_CC fail, Status - %r\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "%a: NVME_SET_CC fail, Status - %r\n", __func__, Status));
     goto ErrorExit;
   }
 
   Status = NvmeWaitController (Private, TRUE);
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a: NvmeWaitController fail, Status - %r\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "%a: NvmeWaitController fail, Status - %r\n", __func__, Status));
     goto ErrorExit;
   }
 
   return EFI_SUCCESS;
 
 ErrorExit:
-  DEBUG ((DEBUG_ERROR, "%a fail, Status: %r\n", __FUNCTION__, Status));
+  DEBUG ((DEBUG_ERROR, "%a fail, Status: %r\n", __func__, Status));
   return Status;
 }
 
@@ -572,7 +572,7 @@ NvmeControllerInit (
   //
   NVME_GET_CAP (Private, &Private->Cap);
   if ((Private->Cap.Css & BIT0) == 0) {
-    DEBUG ((DEBUG_ERROR, "%a: The NVME controller doesn't support NVMe command set.\n", __FUNCTION__));
+    DEBUG ((DEBUG_ERROR, "%a: The NVME controller doesn't support NVMe command set.\n", __func__));
     return EFI_UNSUPPORTED;
   }
 
@@ -580,7 +580,7 @@ NvmeControllerInit (
   // Currently, the driver only supports 4k page size
   //
   if ((Private->Cap.Mpsmin + 12) > EFI_PAGE_SHIFT) {
-    DEBUG ((DEBUG_ERROR, "%a: The driver doesn't support page size other than 4K.\n", __FUNCTION__));
+    DEBUG ((DEBUG_ERROR, "%a: The driver doesn't support page size other than 4K.\n", __func__));
     ASSERT (FALSE);
     return EFI_UNSUPPORTED;
   }
@@ -599,7 +599,7 @@ NvmeControllerInit (
   //
   Status = NvmeDisableController (Private);
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a: NvmeDisableController fail, Status - %r\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "%a: NvmeDisableController fail, Status - %r\n", __func__, Status));
     return Status;
   }
 
@@ -647,7 +647,7 @@ NvmeControllerInit (
   //
   Status = NvmeEnableController (Private);
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a: NvmeEnableController fail, Status - %r\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "%a: NvmeEnableController fail, Status - %r\n", __func__, Status));
     return Status;
   }
 
@@ -663,7 +663,7 @@ NvmeControllerInit (
 
   Status = NvmeIdentifyController (Private, Private->ControllerData);
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a: NvmeIdentifyController fail, Status - %r\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "%a: NvmeIdentifyController fail, Status - %r\n", __func__, Status));
     return Status;
   }
 
@@ -676,7 +676,7 @@ NvmeControllerInit (
     DEBUG ((
       DEBUG_ERROR,
       "%a: Number of Namespaces field in Identify Controller data not supported by the driver.\n",
-      __FUNCTION__
+      __func__
       ));
     return EFI_UNSUPPORTED;
   }
@@ -686,13 +686,13 @@ NvmeControllerInit (
   //
   Status = NvmeCreateIoCompletionQueue (Private);
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a: Create IO completion queue fail, Status - %r\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "%a: Create IO completion queue fail, Status - %r\n", __func__, Status));
     return Status;
   }
 
   Status = NvmeCreateIoSubmissionQueue (Private);
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a: Create IO submission queue fail, Status - %r\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "%a: Create IO submission queue fail, Status - %r\n", __func__, Status));
   }
 
   return Status;
diff --git a/MdeModulePkg/Bus/Pci/NvmExpressPei/NvmExpressPeiPassThru.c b/MdeModulePkg/Bus/Pci/NvmExpressPei/NvmExpressPeiPassThru.c
index dc280ec4e3..5081b53cd5 100644
--- a/MdeModulePkg/Bus/Pci/NvmExpressPei/NvmExpressPeiPassThru.c
+++ b/MdeModulePkg/Bus/Pci/NvmExpressPei/NvmExpressPeiPassThru.c
@@ -57,7 +57,7 @@ NvmeCreatePrpList (
       DEBUG_ERROR,
       "%a: The implementation only supports PrpList number up to 4."
       " But %d are needed here.\n",
-      __FUNCTION__,
+      __func__,
       PrpListNo
       ));
     return 0;
@@ -365,7 +365,7 @@ NvmePassThruExecute (
     DEBUG ((
       DEBUG_ERROR,
       "%a, Invalid parameter: Packet(%lx)\n",
-      __FUNCTION__,
+      __func__,
       (UINTN)Packet
       ));
     return EFI_INVALID_PARAMETER;
@@ -375,7 +375,7 @@ NvmePassThruExecute (
     DEBUG ((
       DEBUG_ERROR,
       "%a, Invalid parameter: NvmeCmd (%lx)/NvmeCompletion(%lx)\n",
-      __FUNCTION__,
+      __func__,
       (UINTN)Packet->NvmeCmd,
       (UINTN)Packet->NvmeCompletion
       ));
@@ -386,7 +386,7 @@ NvmePassThruExecute (
     DEBUG ((
       DEBUG_ERROR,
       "%a, Invalid parameter: QueueId(%lx)\n",
-      __FUNCTION__,
+      __func__,
       (UINTN)Packet->QueueType
       ));
     return EFI_INVALID_PARAMETER;
@@ -407,7 +407,7 @@ NvmePassThruExecute (
     DEBUG ((
       DEBUG_ERROR,
       "%a: Nsid mismatch (%x, %x)\n",
-      __FUNCTION__,
+      __func__,
       Packet->NvmeCmd->Nsid,
       NamespaceId
       ));
@@ -425,7 +425,7 @@ NvmePassThruExecute (
   //
   ASSERT (Sq->Psdt == 0);
   if (Sq->Psdt != 0) {
-    DEBUG ((DEBUG_ERROR, "%a: Does not support SGL mechanism.\n", __FUNCTION__));
+    DEBUG ((DEBUG_ERROR, "%a: Does not support SGL mechanism.\n", __func__));
     return EFI_UNSUPPORTED;
   }
 
@@ -458,7 +458,7 @@ NvmePassThruExecute (
         DEBUG ((
           DEBUG_ERROR,
           "%a: Does not support external IO queues creation request.\n",
-          __FUNCTION__
+          __func__
           ));
         return EFI_UNSUPPORTED;
       }
@@ -480,7 +480,7 @@ NvmePassThruExecute (
                       );
         if (EFI_ERROR (Status) || (MapLength != Packet->TransferLength)) {
           Status = EFI_OUT_OF_RESOURCES;
-          DEBUG ((DEBUG_ERROR, "%a: Fail to map data buffer.\n", __FUNCTION__));
+          DEBUG ((DEBUG_ERROR, "%a: Fail to map data buffer.\n", __func__));
           goto Exit;
         }
 
@@ -498,7 +498,7 @@ NvmePassThruExecute (
                       );
         if (EFI_ERROR (Status) || (MapLength != Packet->MetadataLength)) {
           Status = EFI_OUT_OF_RESOURCES;
-          DEBUG ((DEBUG_ERROR, "%a: Fail to map meta data buffer.\n", __FUNCTION__));
+          DEBUG ((DEBUG_ERROR, "%a: Fail to map meta data buffer.\n", __func__));
           goto Exit;
         }
 
@@ -526,7 +526,7 @@ NvmePassThruExecute (
                    );
     if (Sq->Prp[1] == 0) {
       Status = EFI_OUT_OF_RESOURCES;
-      DEBUG ((DEBUG_ERROR, "%a: Create PRP list fail, Status - %r\n", __FUNCTION__, Status));
+      DEBUG ((DEBUG_ERROR, "%a: Create PRP list fail, Status - %r\n", __func__, Status));
       goto Exit;
     }
   } else if ((Offset + Bytes) > EFI_PAGE_SIZE) {
@@ -568,7 +568,7 @@ NvmePassThruExecute (
   Data32 = ReadUnaligned32 ((UINT32 *)&Private->SqTdbl[QueueId]);
   Status = NVME_SET_SQTDBL (Private, QueueId, &Data32);
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a: NVME_SET_SQTDBL fail, Status - %r\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "%a: NVME_SET_SQTDBL fail, Status - %r\n", __func__, Status));
     goto Exit;
   }
 
@@ -591,7 +591,7 @@ NvmePassThruExecute (
     //
     // Timeout occurs for an NVMe command, reset the controller to abort the outstanding command
     //
-    DEBUG ((DEBUG_ERROR, "%a: Timeout occurs for the PassThru command.\n", __FUNCTION__));
+    DEBUG ((DEBUG_ERROR, "%a: Timeout occurs for the PassThru command.\n", __func__));
     Status = NvmeControllerInit (Private);
     if (EFI_ERROR (Status)) {
       Status = EFI_DEVICE_ERROR;
diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c
index ba4b099bc5..75c9b344ee 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c
@@ -237,7 +237,7 @@ LocatePciExpressCapabilityRegBlock (
       DEBUG ((
         DEBUG_WARN,
         "%a: [%02x|%02x|%02x] failed to access config space at offset 0x%x\n",
-        __FUNCTION__,
+        __func__,
         PciIoDevice->BusNumber,
         PciIoDevice->DeviceNumber,
         PciIoDevice->FunctionNumber,
diff --git a/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c b/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c
index b20bcd310a..d573e532ba 100644
--- a/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c
+++ b/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c
@@ -128,7 +128,7 @@ IntersectIoDescriptor (
       EFI_ERROR (Status) ? DEBUG_ERROR : DEBUG_VERBOSE,
       "%a: %a: add [%Lx, %Lx): %r\n",
       gEfiCallerBaseName,
-      __FUNCTION__,
+      __func__,
       IntersectionBase,
       IntersectionEnd,
       Status
@@ -141,7 +141,7 @@ IntersectIoDescriptor (
     "%a: %a: desc [%Lx, %Lx) type %u conflicts with "
     "aperture [%Lx, %Lx)\n",
     gEfiCallerBaseName,
-    __FUNCTION__,
+    __func__,
     Descriptor->BaseAddress,
     Descriptor->BaseAddress + Descriptor->Length,
     (UINT32)Descriptor->GcdIoType,
@@ -178,7 +178,7 @@ AddIoSpace (
       DEBUG_ERROR,
       "%a: %a: GetIoSpaceMap(): %r\n",
       gEfiCallerBaseName,
-      __FUNCTION__,
+      __func__,
       Status
       ));
     return Status;
@@ -299,7 +299,7 @@ IntersectMemoryDescriptor (
       EFI_ERROR (Status) ? DEBUG_ERROR : DEBUG_VERBOSE,
       "%a: %a: add [%Lx, %Lx): %r\n",
       gEfiCallerBaseName,
-      __FUNCTION__,
+      __func__,
       IntersectionBase,
       IntersectionEnd,
       Status
@@ -312,7 +312,7 @@ IntersectMemoryDescriptor (
     "%a: %a: desc [%Lx, %Lx) type %u cap %Lx conflicts "
     "with aperture [%Lx, %Lx) cap %Lx\n",
     gEfiCallerBaseName,
-    __FUNCTION__,
+    __func__,
     Descriptor->BaseAddress,
     Descriptor->BaseAddress + Descriptor->Length,
     (UINT32)Descriptor->GcdMemoryType,
@@ -353,7 +353,7 @@ AddMemoryMappedIoSpace (
       DEBUG_ERROR,
       "%a: %a: GetMemorySpaceMap(): %r\n",
       gEfiCallerBaseName,
-      __FUNCTION__,
+      __func__,
       Status
       ));
     return Status;
@@ -955,7 +955,7 @@ NotifyPhase (
               DEBUG ((
                 DEBUG_ERROR,
                 "[%a:%d] Translation %lx is not aligned to %lx!\n",
-                __FUNCTION__,
+                __func__,
                 DEBUG_LINE_NUMBER,
                 Translation,
                 Alignment
diff --git a/MdeModulePkg/Bus/Pci/SdMmcPciHcDxe/SdMmcPciHcDxe.c b/MdeModulePkg/Bus/Pci/SdMmcPciHcDxe/SdMmcPciHcDxe.c
index ab2becdd19..8496ce4727 100644
--- a/MdeModulePkg/Bus/Pci/SdMmcPciHcDxe/SdMmcPciHcDxe.c
+++ b/MdeModulePkg/Bus/Pci/SdMmcPciHcDxe/SdMmcPciHcDxe.c
@@ -641,7 +641,7 @@ SdMmcPciHcDriverBindingStart (
       DEBUG ((
         DEBUG_INFO,
         "%a: found SD/MMC override protocol\n",
-        __FUNCTION__
+        __func__
         ));
     }
   }
@@ -676,7 +676,7 @@ SdMmcPciHcDriverBindingStart (
           DEBUG ((
             DEBUG_WARN,
             "%a: Failed to override capability - %r\n",
-            __FUNCTION__,
+            __func__,
             Status
             ));
           continue;
@@ -691,7 +691,7 @@ SdMmcPciHcDriverBindingStart (
                               (VOID *)&Private->Slot[Slot].OperatingParameters
                               );
         if (EFI_ERROR (Status)) {
-          DEBUG ((DEBUG_WARN, "%a: Failed to get operating parameters, using defaults\n", __FUNCTION__));
+          DEBUG ((DEBUG_WARN, "%a: Failed to get operating parameters, using defaults\n", __func__));
         }
       }
     }
diff --git a/MdeModulePkg/Bus/Pci/SdMmcPciHcDxe/SdMmcPciHci.c b/MdeModulePkg/Bus/Pci/SdMmcPciHcDxe/SdMmcPciHci.c
index dd45167a00..aab6815328 100644
--- a/MdeModulePkg/Bus/Pci/SdMmcPciHcDxe/SdMmcPciHci.c
+++ b/MdeModulePkg/Bus/Pci/SdMmcPciHcDxe/SdMmcPciHci.c
@@ -498,7 +498,7 @@ SdMmcHcReset (
       DEBUG ((
         DEBUG_WARN,
         "%a: SD/MMC pre reset notifier callback failed - %r\n",
-        __FUNCTION__,
+        __func__,
         Status
         ));
       return Status;
@@ -556,7 +556,7 @@ SdMmcHcReset (
       DEBUG ((
         DEBUG_WARN,
         "%a: SD/MMC post reset notifier callback failed - %r\n",
-        __FUNCTION__,
+        __func__,
         Status
         ));
     }
@@ -942,7 +942,7 @@ SdMmcHcClockSupply (
       DEBUG ((
         DEBUG_ERROR,
         "%a: SD/MMC switch clock freq post notifier callback failed - %r\n",
-        __FUNCTION__,
+        __func__,
         Status
         ));
       return Status;
@@ -1234,7 +1234,7 @@ SdMmcHcInitHost (
       DEBUG ((
         DEBUG_WARN,
         "%a: SD/MMC pre init notifier callback failed - %r\n",
-        __FUNCTION__,
+        __func__,
         Status
         ));
       return Status;
@@ -1286,7 +1286,7 @@ SdMmcHcInitHost (
       DEBUG ((
         DEBUG_WARN,
         "%a: SD/MMC post init notifier callback failed - %r\n",
-        __FUNCTION__,
+        __func__,
         Status
         ));
     }
@@ -1375,7 +1375,7 @@ SdMmcHcUhsSignaling (
       DEBUG ((
         DEBUG_ERROR,
         "%a: SD/MMC uhs signaling notifier callback failed - %r\n",
-        __FUNCTION__,
+        __func__,
         Status
         ));
       return Status;
diff --git a/MdeModulePkg/Bus/Pci/XhciDxe/Xhci.c b/MdeModulePkg/Bus/Pci/XhciDxe/Xhci.c
index d8fa41f68f..62682dd27c 100644
--- a/MdeModulePkg/Bus/Pci/XhciDxe/Xhci.c
+++ b/MdeModulePkg/Bus/Pci/XhciDxe/Xhci.c
@@ -2059,7 +2059,7 @@ XhcDriverBindingStart (
       DEBUG ((
         DEBUG_WARN,
         "%a: failed to enable 64-bit DMA on 64-bit capable controller @ %p (%r)\n",
-        __FUNCTION__,
+        __func__,
         Controller,
         Status
         ));
diff --git a/MdeModulePkg/Bus/Pci/XhciDxe/XhciSched.c b/MdeModulePkg/Bus/Pci/XhciDxe/XhciSched.c
index 4b7462704a..298fb88b81 100644
--- a/MdeModulePkg/Bus/Pci/XhciDxe/XhciSched.c
+++ b/MdeModulePkg/Bus/Pci/XhciDxe/XhciSched.c
@@ -1495,7 +1495,7 @@ XhciInsertAsyncIntTransfer (
 
   Data = AllocateZeroPool (DataLen);
   if (Data == NULL) {
-    DEBUG ((DEBUG_ERROR, "%a: failed to allocate buffer\n", __FUNCTION__));
+    DEBUG ((DEBUG_ERROR, "%a: failed to allocate buffer\n", __func__));
     return NULL;
   }
 
@@ -1513,7 +1513,7 @@ XhciInsertAsyncIntTransfer (
           Context
           );
   if (Urb == NULL) {
-    DEBUG ((DEBUG_ERROR, "%a: failed to create URB\n", __FUNCTION__));
+    DEBUG ((DEBUG_ERROR, "%a: failed to create URB\n", __func__));
     FreePool (Data);
     return NULL;
   }
diff --git a/MdeModulePkg/Bus/Scsi/ScsiDiskDxe/ScsiDisk.c b/MdeModulePkg/Bus/Scsi/ScsiDiskDxe/ScsiDisk.c
index 873581d817..670f70caf4 100644
--- a/MdeModulePkg/Bus/Scsi/ScsiDiskDxe/ScsiDisk.c
+++ b/MdeModulePkg/Bus/Scsi/ScsiDiskDxe/ScsiDisk.c
@@ -2593,7 +2593,7 @@ ScsiDiskInquiryDevice (
           DEBUG ((
             DEBUG_WARN,
             "%a: invalid PageLength (%u) in Supported VPD Pages page\n",
-            __FUNCTION__,
+            __func__,
             (UINT32)PageLength
             ));
           PageLength = 0;
@@ -2606,7 +2606,7 @@ ScsiDiskInquiryDevice (
           DEBUG ((
             DEBUG_WARN,
             "%a: Supported VPD Pages page doesn't start with code 0x%02x\n",
-            __FUNCTION__,
+            __func__,
             EFI_SCSI_PAGE_CODE_SUPPORTED_VPD
             ));
           PageLength = 0;
@@ -2626,7 +2626,7 @@ ScsiDiskInquiryDevice (
             DEBUG ((
               DEBUG_WARN,
               "%a: non-ascending code in Supported VPD Pages page @ %u\n",
-              __FUNCTION__,
+              __func__,
               Index
               ));
             Index      = 0;
diff --git a/MdeModulePkg/Core/Dxe/Dispatcher/Dispatcher.c b/MdeModulePkg/Core/Dxe/Dispatcher/Dispatcher.c
index fb9ae3ce78..cf9d556877 100644
--- a/MdeModulePkg/Core/Dxe/Dispatcher/Dispatcher.c
+++ b/MdeModulePkg/Core/Dxe/Dispatcher/Dispatcher.c
@@ -1095,7 +1095,7 @@ CoreProcessFvImageFile (
         DEBUG ((
           DEBUG_INFO,
           "%a() FV at 0x%x, FvAlignment required is 0x%x\n",
-          __FUNCTION__,
+          __func__,
           FvHeader,
           FvAlignment
           ));
diff --git a/MdeModulePkg/Core/Dxe/DxeMain/DxeMain.c b/MdeModulePkg/Core/Dxe/DxeMain/DxeMain.c
index 4683016ed7..0e0f9769b9 100644
--- a/MdeModulePkg/Core/Dxe/DxeMain/DxeMain.c
+++ b/MdeModulePkg/Core/Dxe/DxeMain/DxeMain.c
@@ -315,7 +315,7 @@ DxeMain (
   DEBUG ((
     DEBUG_INFO,
     "%a: MemoryBaseAddress=0x%Lx MemoryLength=0x%Lx\n",
-    __FUNCTION__,
+    __func__,
     MemoryBaseAddress,
     MemoryLength
     ));
diff --git a/MdeModulePkg/Core/Dxe/Misc/MemoryProtection.c b/MdeModulePkg/Core/Dxe/Misc/MemoryProtection.c
index b89ab046fa..7cc829b174 100644
--- a/MdeModulePkg/Core/Dxe/Misc/MemoryProtection.c
+++ b/MdeModulePkg/Core/Dxe/Misc/MemoryProtection.c
@@ -838,7 +838,7 @@ InitializeDxeNxMemoryProtectionPolicy (
         DEBUG ((
           DEBUG_INFO,
           "%a: StackBase = 0x%016lx  StackSize = 0x%016lx\n",
-          __FUNCTION__,
+          __func__,
           MemoryHob->AllocDescriptor.MemoryBaseAddress,
           MemoryHob->AllocDescriptor.MemoryLength
           ));
@@ -864,7 +864,7 @@ InitializeDxeNxMemoryProtectionPolicy (
   DEBUG ((
     DEBUG_INFO,
     "%a: applying strict permissions to active memory regions\n",
-    __FUNCTION__
+    __func__
     ));
 
   MergeMemoryMapForProtectionPolicy (MemoryMap, &MemoryMapSize, DescriptorSize);
@@ -926,7 +926,7 @@ InitializeDxeNxMemoryProtectionPolicy (
     DEBUG ((
       DEBUG_INFO,
       "%a: applying strict permissions to inactive memory regions\n",
-      __FUNCTION__
+      __func__
       ));
 
     CoreAcquireGcdMemoryLock ();
diff --git a/MdeModulePkg/Core/Dxe/SectionExtraction/CoreSectionExtraction.c b/MdeModulePkg/Core/Dxe/SectionExtraction/CoreSectionExtraction.c
index b8d4184b50..2152833ff6 100644
--- a/MdeModulePkg/Core/Dxe/SectionExtraction/CoreSectionExtraction.c
+++ b/MdeModulePkg/Core/Dxe/SectionExtraction/CoreSectionExtraction.c
@@ -1304,7 +1304,7 @@ GetSection (
         DEBUG ((
           DEBUG_ERROR,
           "%a: recursion aborted due to nesting depth\n",
-          __FUNCTION__
+          __func__
           ));
         //
         // Map "aborted" to "not found".
diff --git a/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c b/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c
index fdeaaa39d8..4bc7b749b0 100644
--- a/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c
+++ b/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c
@@ -369,7 +369,7 @@ HandOffToDxeCore (
     DEBUG ((
       DEBUG_INFO,
       "%a() Stack Base: 0x%lx, Stack Size: 0x%x\n",
-      __FUNCTION__,
+      __func__,
       BaseOfStack,
       STACK_SIZE
       ));
@@ -457,7 +457,7 @@ HandOffToDxeCore (
     DEBUG ((
       DEBUG_INFO,
       "%a() Stack Base: 0x%lx, Stack Size: 0x%x\n",
-      __FUNCTION__,
+      __func__,
       BaseOfStack,
       STACK_SIZE
       ));
diff --git a/MdeModulePkg/Core/DxeIplPeim/RiscV64/DxeLoadFunc.c b/MdeModulePkg/Core/DxeIplPeim/RiscV64/DxeLoadFunc.c
index f7b57df1c4..b3567d88f7 100644
--- a/MdeModulePkg/Core/DxeIplPeim/RiscV64/DxeLoadFunc.c
+++ b/MdeModulePkg/Core/DxeIplPeim/RiscV64/DxeLoadFunc.c
@@ -36,7 +36,7 @@ HandOffToDxeCore (
   //
   BaseOfStack = AllocatePages (EFI_SIZE_TO_PAGES (STACK_SIZE));
   if (BaseOfStack == NULL) {
-    DEBUG ((DEBUG_ERROR, "%a: Can't allocate memory for stack.", __FUNCTION__));
+    DEBUG ((DEBUG_ERROR, "%a: Can't allocate memory for stack.", __func__));
     ASSERT (FALSE);
   }
 
@@ -52,7 +52,7 @@ HandOffToDxeCore (
   //
   Status = PeiServicesInstallPpi (&gEndOfPeiSignalPpi);
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a: Fail to signal End of PEI event.", __FUNCTION__));
+    DEBUG ((DEBUG_ERROR, "%a: Fail to signal End of PEI event.", __func__));
     ASSERT (FALSE);
   }
 
diff --git a/MdeModulePkg/Core/Pei/Dispatcher/Dispatcher.c b/MdeModulePkg/Core/Pei/Dispatcher/Dispatcher.c
index 3552feda8f..d8284f9f4f 100644
--- a/MdeModulePkg/Core/Pei/Dispatcher/Dispatcher.c
+++ b/MdeModulePkg/Core/Pei/Dispatcher/Dispatcher.c
@@ -101,7 +101,7 @@ DiscoverPeimsAndOrderWithApriori (
   DEBUG ((
     DEBUG_INFO,
     "%a(): Found 0x%x PEI FFS files in the %dth FV\n",
-    __FUNCTION__,
+    __func__,
     PeimCount,
     Private->CurrentPeimFvCount
     ));
diff --git a/MdeModulePkg/Core/Pei/FwVol/FwVol.c b/MdeModulePkg/Core/Pei/FwVol/FwVol.c
index 60bbe57332..f7cc94c6eb 100644
--- a/MdeModulePkg/Core/Pei/FwVol/FwVol.c
+++ b/MdeModulePkg/Core/Pei/FwVol/FwVol.c
@@ -1494,7 +1494,7 @@ ProcessFvFile (
       DEBUG ((
         DEBUG_INFO,
         "%a() FV at 0x%x, FvAlignment required is 0x%x\n",
-        __FUNCTION__,
+        __func__,
         FvHeader,
         FvAlignment
         ));
diff --git a/MdeModulePkg/Library/DxeCapsuleLibFmp/DxeCapsuleReportLib.c b/MdeModulePkg/Library/DxeCapsuleLibFmp/DxeCapsuleReportLib.c
index efc6b4ce26..a1523428cd 100644
--- a/MdeModulePkg/Library/DxeCapsuleLibFmp/DxeCapsuleReportLib.c
+++ b/MdeModulePkg/Library/DxeCapsuleLibFmp/DxeCapsuleReportLib.c
@@ -502,7 +502,7 @@ InitCapsuleVariable (
   // Locate the VariablePolicy protocol
   Status = gBS->LocateProtocol (&gEdkiiVariablePolicyProtocolGuid, NULL, (VOID **)&VariablePolicy);
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "DxeCapsuleReportLib %a - Could not locate VariablePolicy protocol! %r\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "DxeCapsuleReportLib %a - Could not locate VariablePolicy protocol! %r\n", __func__, Status));
     ASSERT_EFI_ERROR (Status);
   }
 
diff --git a/MdeModulePkg/Library/PiDxeS3BootScriptLib/BootScriptSave.c b/MdeModulePkg/Library/PiDxeS3BootScriptLib/BootScriptSave.c
index 8c7b58b2f9..a6af2e8485 100644
--- a/MdeModulePkg/Library/PiDxeS3BootScriptLib/BootScriptSave.c
+++ b/MdeModulePkg/Library/PiDxeS3BootScriptLib/BootScriptSave.c
@@ -579,7 +579,7 @@ S3BootScriptLibDeinitialize (
     return RETURN_SUCCESS;
   }
 
-  DEBUG ((DEBUG_INFO, "%a() in %a module\n", __FUNCTION__, gEfiCallerBaseName));
+  DEBUG ((DEBUG_INFO, "%a() in %a module\n", __func__, gEfiCallerBaseName));
 
   if (mEventDxeSmmReadyToLock != NULL) {
     //
diff --git a/MdeModulePkg/Library/ResetUtilityLib/ResetUtility.c b/MdeModulePkg/Library/ResetUtilityLib/ResetUtility.c
index 50131a431f..4ca8425705 100644
--- a/MdeModulePkg/Library/ResetUtilityLib/ResetUtility.c
+++ b/MdeModulePkg/Library/ResetUtilityLib/ResetUtility.c
@@ -132,7 +132,7 @@ GetResetPlatformSpecificGuid (
   //
   if ((ResetDataStringSize < DataSize) && ((DataSize - ResetDataStringSize) >= sizeof (GUID))) {
     ResetSubtypeGuid = (GUID *)((UINT8 *)ResetData + ResetDataStringSize);
-    DEBUG ((DEBUG_VERBOSE, "%a - Detected reset subtype %g...\n", __FUNCTION__, ResetSubtypeGuid));
+    DEBUG ((DEBUG_VERBOSE, "%a - Detected reset subtype %g...\n", __func__, ResetSubtypeGuid));
     return ResetSubtypeGuid;
   }
 
diff --git a/MdeModulePkg/Library/UefiBootManagerLib/BmBoot.c b/MdeModulePkg/Library/UefiBootManagerLib/BmBoot.c
index bde22fa659..c3763c4483 100644
--- a/MdeModulePkg/Library/UefiBootManagerLib/BmBoot.c
+++ b/MdeModulePkg/Library/UefiBootManagerLib/BmBoot.c
@@ -1448,7 +1448,7 @@ BmExpandLoadFile (
       "%a:%a: failed to allocate reserved pages: "
       "BufferSize=%Lu LoadFile=\"%s\" FilePath=\"%s\"\n",
       gEfiCallerBaseName,
-      __FUNCTION__,
+      __func__,
       (UINT64)BufferSize,
       LoadFileText,
       FileText
diff --git a/MdeModulePkg/Library/UefiBootManagerLib/BmDriverHealth.c b/MdeModulePkg/Library/UefiBootManagerLib/BmDriverHealth.c
index 46a2fa2016..46a8b780e3 100644
--- a/MdeModulePkg/Library/UefiBootManagerLib/BmDriverHealth.c
+++ b/MdeModulePkg/Library/UefiBootManagerLib/BmDriverHealth.c
@@ -581,7 +581,7 @@ BmRepairAllControllers (
       DEBUG ((
         DEBUG_ERROR,
         "[%a:%d] Repair failed after %d retries.\n",
-        __FUNCTION__,
+        __func__,
         DEBUG_LINE_NUMBER,
         ReconnectRepairCount
         ));
diff --git a/MdeModulePkg/Library/VarCheckPolicyLib/VarCheckPolicyLib.c b/MdeModulePkg/Library/VarCheckPolicyLib/VarCheckPolicyLib.c
index da90f4fc6a..5de46133bb 100644
--- a/MdeModulePkg/Library/VarCheckPolicyLib/VarCheckPolicyLib.c
+++ b/MdeModulePkg/Library/VarCheckPolicyLib/VarCheckPolicyLib.c
@@ -95,7 +95,7 @@ VarCheckPolicyLibMmiHandler (
   //
   // If either of the pointers are NULL, we can't proceed.
   if ((CommBuffer == NULL) || (CommBufferSize == NULL)) {
-    DEBUG ((DEBUG_INFO, "%a - Invalid comm buffer pointers!\n", __FUNCTION__));
+    DEBUG ((DEBUG_INFO, "%a - Invalid comm buffer pointers!\n", __func__));
     return EFI_INVALID_PARAMETER;
   }
 
@@ -105,14 +105,14 @@ VarCheckPolicyLibMmiHandler (
   if ((InternalCommBufferSize > VAR_CHECK_POLICY_MM_COMM_BUFFER_SIZE) ||
       !VarCheckPolicyIsBufferOutsideValid ((UINTN)CommBuffer, (UINT64)InternalCommBufferSize))
   {
-    DEBUG ((DEBUG_ERROR, "%a - Invalid CommBuffer supplied! 0x%016lX[0x%016lX]\n", __FUNCTION__, CommBuffer, InternalCommBufferSize));
+    DEBUG ((DEBUG_ERROR, "%a - Invalid CommBuffer supplied! 0x%016lX[0x%016lX]\n", __func__, CommBuffer, InternalCommBufferSize));
     return EFI_INVALID_PARAMETER;
   }
 
   // If the size does not meet a minimum threshold, we cannot proceed.
   ExpectedSize = sizeof (VAR_CHECK_POLICY_COMM_HEADER);
   if (InternalCommBufferSize < ExpectedSize) {
-    DEBUG ((DEBUG_INFO, "%a - Bad comm buffer size! %d < %d\n", __FUNCTION__, InternalCommBufferSize, ExpectedSize));
+    DEBUG ((DEBUG_INFO, "%a - Bad comm buffer size! %d < %d\n", __func__, InternalCommBufferSize, ExpectedSize));
     return EFI_INVALID_PARAMETER;
   }
 
@@ -128,7 +128,7 @@ VarCheckPolicyLibMmiHandler (
   if ((InternalPolicyCommmHeader->Signature != VAR_CHECK_POLICY_COMM_SIG) ||
       (InternalPolicyCommmHeader->Revision != VAR_CHECK_POLICY_COMM_REVISION))
   {
-    DEBUG ((DEBUG_INFO, "%a - Signature or revision are incorrect!\n", __FUNCTION__));
+    DEBUG ((DEBUG_INFO, "%a - Signature or revision are incorrect!\n", __func__));
     // We have verified the buffer is not null and have enough size to hold Result field.
     PolicyCommmHeader->Result = EFI_INVALID_PARAMETER;
     return EFI_SUCCESS;
@@ -157,7 +157,7 @@ VarCheckPolicyLibMmiHandler (
       // This add should be safe because these are fixed sizes so far.
       ExpectedSize += sizeof (VAR_CHECK_POLICY_COMM_IS_ENABLED_PARAMS);
       if (InternalCommBufferSize < ExpectedSize) {
-        DEBUG ((DEBUG_INFO, "%a - Bad comm buffer size! %d < %d\n", __FUNCTION__, InternalCommBufferSize, ExpectedSize));
+        DEBUG ((DEBUG_INFO, "%a - Bad comm buffer size! %d < %d\n", __func__, InternalCommBufferSize, ExpectedSize));
         PolicyCommmHeader->Result = EFI_INVALID_PARAMETER;
         break;
       }
@@ -173,7 +173,7 @@ VarCheckPolicyLibMmiHandler (
       // This add should be safe because these are fixed sizes so far.
       ExpectedSize += sizeof (VARIABLE_POLICY_ENTRY);
       if (InternalCommBufferSize < ExpectedSize) {
-        DEBUG ((DEBUG_INFO, "%a - Bad comm buffer size! %d < %d\n", __FUNCTION__, InternalCommBufferSize, ExpectedSize));
+        DEBUG ((DEBUG_INFO, "%a - Bad comm buffer size! %d < %d\n", __func__, InternalCommBufferSize, ExpectedSize));
         PolicyCommmHeader->Result = EFI_INVALID_PARAMETER;
         break;
       }
@@ -186,7 +186,7 @@ VarCheckPolicyLibMmiHandler (
           EFI_ERROR (SafeUintnAdd (sizeof (VAR_CHECK_POLICY_COMM_HEADER), PolicyEntry->Size, &ExpectedSize)) ||
           (InternalCommBufferSize < ExpectedSize))
       {
-        DEBUG ((DEBUG_INFO, "%a - Bad policy entry contents!\n", __FUNCTION__));
+        DEBUG ((DEBUG_INFO, "%a - Bad policy entry contents!\n", __func__));
         PolicyCommmHeader->Result = EFI_INVALID_PARAMETER;
         break;
       }
@@ -199,7 +199,7 @@ VarCheckPolicyLibMmiHandler (
       // This add should be safe because these are fixed sizes so far.
       ExpectedSize += sizeof (VAR_CHECK_POLICY_COMM_DUMP_PARAMS) + VAR_CHECK_POLICY_MM_DUMP_BUFFER_SIZE;
       if (InternalCommBufferSize < ExpectedSize) {
-        DEBUG ((DEBUG_INFO, "%a - Bad comm buffer size! %d < %d\n", __FUNCTION__, InternalCommBufferSize, ExpectedSize));
+        DEBUG ((DEBUG_INFO, "%a - Bad comm buffer size! %d < %d\n", __func__, InternalCommBufferSize, ExpectedSize));
         PolicyCommmHeader->Result = EFI_INVALID_PARAMETER;
         break;
       }
@@ -298,7 +298,7 @@ VarCheckPolicyLibMmiHandler (
 
     default:
       // Mark unknown requested command as EFI_UNSUPPORTED.
-      DEBUG ((DEBUG_INFO, "%a - Invalid command requested! %d\n", __FUNCTION__, PolicyCommmHeader->Command));
+      DEBUG ((DEBUG_INFO, "%a - Invalid command requested! %d\n", __func__, PolicyCommmHeader->Command));
       PolicyCommmHeader->Result = EFI_UNSUPPORTED;
       break;
   }
@@ -306,7 +306,7 @@ VarCheckPolicyLibMmiHandler (
   DEBUG ((
     DEBUG_VERBOSE,
     "%a - Command %d returning %r.\n",
-    __FUNCTION__,
+    __func__,
     PolicyCommmHeader->Command,
     PolicyCommmHeader->Result
     ));
@@ -349,7 +349,7 @@ VarCheckPolicyLibCommonConstructor (
   }
   // Otherwise, there's not much we can do.
   else {
-    DEBUG ((DEBUG_ERROR, "%a - Cannot Initialize VariablePolicyLib! %r\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "%a - Cannot Initialize VariablePolicyLib! %r\n", __func__, Status));
     ASSERT_EFI_ERROR (Status);
   }
 
diff --git a/MdeModulePkg/Library/VariablePolicyLib/VariablePolicyLib.c b/MdeModulePkg/Library/VariablePolicyLib/VariablePolicyLib.c
index 82dae67ef5..214f76ab96 100644
--- a/MdeModulePkg/Library/VariablePolicyLib/VariablePolicyLib.c
+++ b/MdeModulePkg/Library/VariablePolicyLib/VariablePolicyLib.c
@@ -521,7 +521,7 @@ ValidateSetVariable (
         DEBUG ((
           DEBUG_VERBOSE,
           "%a - Bad Size. 0x%X <> 0x%X-0x%X\n",
-          __FUNCTION__,
+          __func__,
           DataSize,
           ActivePolicy->MinSize,
           ActivePolicy->MaxSize
@@ -537,7 +537,7 @@ ValidateSetVariable (
         DEBUG ((
           DEBUG_VERBOSE,
           "%a - Bad Attributes. 0x%X <> 0x%X:0x%X\n",
-          __FUNCTION__,
+          __func__,
           Attributes,
           ActivePolicy->AttributesMustHave,
           ActivePolicy->AttributesCantHave
@@ -598,7 +598,7 @@ ValidateSetVariable (
   }
 
 Exit:
-  DEBUG ((DEBUG_VERBOSE, "%a - Variable (%g:%s) returning %r.\n", __FUNCTION__, VendorGuid, VariableName, ReturnStatus));
+  DEBUG ((DEBUG_VERBOSE, "%a - Variable (%g:%s) returning %r.\n", __func__, VendorGuid, VariableName, ReturnStatus));
   return ReturnStatus;
 }
 
diff --git a/MdeModulePkg/Universal/CapsulePei/UefiCapsule.c b/MdeModulePkg/Universal/CapsulePei/UefiCapsule.c
index cdeffa9113..8e26a7d795 100644
--- a/MdeModulePkg/Universal/CapsulePei/UefiCapsule.c
+++ b/MdeModulePkg/Universal/CapsulePei/UefiCapsule.c
@@ -344,7 +344,7 @@ Thunk32To64 (
     DEBUG ((
       DEBUG_INFO,
       "%a() Stack Base: 0x%lx, Stack Size: 0x%lx\n",
-      __FUNCTION__,
+      __func__,
       Context->StackBufferBase,
       Context->StackBufferLength
       ));
@@ -917,7 +917,7 @@ GetScatterGatherHeadEntries (
   CapsuleDataPtr64  = 0;
 
   if ((ListLength == NULL) || (HeadList == NULL)) {
-    DEBUG ((DEBUG_ERROR, "%a Invalid parameters.  Inputs can't be NULL\n", __FUNCTION__));
+    DEBUG ((DEBUG_ERROR, "%a Invalid parameters.  Inputs can't be NULL\n", __func__));
     ASSERT (ListLength != NULL);
     ASSERT (HeadList != NULL);
     return EFI_INVALID_PARAMETER;
@@ -1022,7 +1022,7 @@ GetScatterGatherHeadEntries (
   }
 
   if (ValidIndex == 0) {
-    DEBUG ((DEBUG_ERROR, "%a didn't find any SG lists in variables\n", __FUNCTION__));
+    DEBUG ((DEBUG_ERROR, "%a didn't find any SG lists in variables\n", __func__));
     return EFI_NOT_FOUND;
   }
 
@@ -1101,7 +1101,7 @@ CapsuleCoalesce (
   //
   Status = GetScatterGatherHeadEntries (&ListLength, &VariableArrayAddress);
   if (EFI_ERROR (Status) || (VariableArrayAddress == NULL)) {
-    DEBUG ((DEBUG_ERROR, "%a failed to get Scatter Gather List Head Entries.  Status = %r\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "%a failed to get Scatter Gather List Head Entries.  Status = %r\n", __func__, Status));
     goto Done;
   }
 
diff --git a/MdeModulePkg/Universal/CapsulePei/X64/X64Entry.c b/MdeModulePkg/Universal/CapsulePei/X64/X64Entry.c
index 05941f9f8d..4085f371ab 100644
--- a/MdeModulePkg/Universal/CapsulePei/X64/X64Entry.c
+++ b/MdeModulePkg/Universal/CapsulePei/X64/X64Entry.c
@@ -277,7 +277,7 @@ _ModuleEntryPoint (
   DEBUG ((
     DEBUG_INFO,
     "%a() Stack Base: 0x%lx, Stack Size: 0x%lx\n",
-    __FUNCTION__,
+    __func__,
     EntrypointContext->StackBufferBase,
     EntrypointContext->StackBufferLength
     ));
diff --git a/MdeModulePkg/Universal/Disk/PartitionDxe/Udf.c b/MdeModulePkg/Universal/Disk/PartitionDxe/Udf.c
index 098e4fec66..6e10defe59 100644
--- a/MdeModulePkg/Universal/Disk/PartitionDxe/Udf.c
+++ b/MdeModulePkg/Universal/Disk/PartitionDxe/Udf.c
@@ -114,7 +114,7 @@ FindAnchorVolumeDescriptorPointer (
     DEBUG ((
       DEBUG_ERROR,
       "%a: Media block size 0x%x unable to hold an AVDP.\n",
-      __FUNCTION__,
+      __func__,
       BlockSize
       ));
     return EFI_UNSUPPORTED;
@@ -140,7 +140,7 @@ FindAnchorVolumeDescriptorPointer (
   // Check if read block is a valid AVDP descriptor
   //
   if (DescriptorTag->TagIdentifier == UdfAnchorVolumeDescriptorPointer) {
-    DEBUG ((DEBUG_INFO, "%a: found AVDP at block %d\n", __FUNCTION__, 256));
+    DEBUG ((DEBUG_INFO, "%a: found AVDP at block %d\n", __func__, 256));
     AvdpsCount++;
   }
 
@@ -167,7 +167,7 @@ FindAnchorVolumeDescriptorPointer (
     DEBUG ((
       DEBUG_INFO,
       "%a: found AVDP at block %Ld\n",
-      __FUNCTION__,
+      __func__,
       EndLBA - 256
       ));
     return EFI_SUCCESS;
@@ -251,13 +251,13 @@ FindAnchorVolumeDescriptorPointer (
       DEBUG ((
         DEBUG_WARN,
         "%a: found AVDP at block %Ld\n",
-        __FUNCTION__,
+        __func__,
         LastAvdpBlockNum
         ));
       DEBUG ((
         DEBUG_WARN,
         "%a: correcting last block from %Ld to %Ld\n",
-        __FUNCTION__,
+        __func__,
         EndLBA,
         LastAvdpBlockNum
         ));
diff --git a/MdeModulePkg/Universal/Disk/UdfDxe/File.c b/MdeModulePkg/Universal/Disk/UdfDxe/File.c
index 6cd197046f..ca2f3e0766 100644
--- a/MdeModulePkg/Universal/Disk/UdfDxe/File.c
+++ b/MdeModulePkg/Universal/Disk/UdfDxe/File.c
@@ -262,7 +262,7 @@ UdfOpen (
     DEBUG ((
       DEBUG_ERROR,
       "%a: GetFileSize() fails with status - %r.\n",
-      __FUNCTION__,
+      __func__,
       Status
       ));
     goto Error_Get_File_Size;
diff --git a/MdeModulePkg/Universal/Disk/UdfDxe/FileSystemOperations.c b/MdeModulePkg/Universal/Disk/UdfDxe/FileSystemOperations.c
index 2998c3369c..86020de6e0 100644
--- a/MdeModulePkg/Universal/Disk/UdfDxe/FileSystemOperations.c
+++ b/MdeModulePkg/Universal/Disk/UdfDxe/FileSystemOperations.c
@@ -298,7 +298,7 @@ GetLongAdLsn (
     DEBUG ((
       DEBUG_ERROR,
       "%a: Fail to get the Partition Descriptor from the given Long Allocation Descriptor.\n",
-      __FUNCTION__
+      __func__
       ));
     return EFI_UNSUPPORTED;
   }
diff --git a/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWrite.c b/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWrite.c
index 53f9aefb2d..10a67767eb 100644
--- a/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWrite.c
+++ b/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWrite.c
@@ -731,7 +731,7 @@ FtwRestart (
     return EFI_ABORTED;
   }
 
-  DEBUG ((DEBUG_INFO, "%a(): success\n", __FUNCTION__));
+  DEBUG ((DEBUG_INFO, "%a(): success\n", __func__));
   return EFI_SUCCESS;
 }
 
@@ -787,7 +787,7 @@ FtwAbort (
 
   FtwDevice->FtwLastWriteHeader->Complete = FTW_VALID_STATE;
 
-  DEBUG ((DEBUG_INFO, "%a(): success\n", __FUNCTION__));
+  DEBUG ((DEBUG_INFO, "%a(): success\n", __func__));
   return EFI_SUCCESS;
 }
 
@@ -901,7 +901,7 @@ FtwGetLastWrite (
     Status = EFI_SUCCESS;
   }
 
-  DEBUG ((DEBUG_INFO, "%a(): success\n", __FUNCTION__));
+  DEBUG ((DEBUG_INFO, "%a(): success\n", __func__));
 
   return Status;
 }
diff --git a/MdeModulePkg/Universal/FaultTolerantWriteDxe/FtwMisc.c b/MdeModulePkg/Universal/FaultTolerantWriteDxe/FtwMisc.c
index f1335870e7..508184f7a0 100644
--- a/MdeModulePkg/Universal/FaultTolerantWriteDxe/FtwMisc.c
+++ b/MdeModulePkg/Universal/FaultTolerantWriteDxe/FtwMisc.c
@@ -1320,7 +1320,7 @@ InitFtwProtocol (
       DEBUG ((
         DEBUG_INFO,
         "Ftw: Restart working block update in %a() - %r\n",
-        __FUNCTION__,
+        __func__,
         Status
         ));
       FtwAbort (&FtwDevice->FtwInstance);
diff --git a/MdeModulePkg/Universal/PCD/Dxe/Service.c b/MdeModulePkg/Universal/PCD/Dxe/Service.c
index 5ade8d988b..1ae06a639c 100644
--- a/MdeModulePkg/Universal/PCD/Dxe/Service.c
+++ b/MdeModulePkg/Universal/PCD/Dxe/Service.c
@@ -1632,7 +1632,7 @@ GetExPcdTokenNumber (
     }
   }
 
-  DEBUG ((DEBUG_ERROR, "%a: Failed to find PCD with GUID: %g and token number: %d\n", __FUNCTION__, Guid, ExTokenNumber));
+  DEBUG ((DEBUG_ERROR, "%a: Failed to find PCD with GUID: %g and token number: %d\n", __func__, Guid, ExTokenNumber));
   ASSERT (FALSE);
 
   return 0;
diff --git a/MdeModulePkg/Universal/SmbiosDxe/SmbiosDxe.c b/MdeModulePkg/Universal/SmbiosDxe/SmbiosDxe.c
index dd077bb0cf..1a86e69d3c 100644
--- a/MdeModulePkg/Universal/SmbiosDxe/SmbiosDxe.c
+++ b/MdeModulePkg/Universal/SmbiosDxe/SmbiosDxe.c
@@ -1157,7 +1157,7 @@ SmbiosCreateTable (
     DEBUG ((
       DEBUG_INFO,
       "%a() re-allocate SMBIOS 32-bit table\n",
-      __FUNCTION__
+      __func__
       ));
     if (EntryPointStructure->TableAddress != 0) {
       //
@@ -1329,7 +1329,7 @@ SmbiosCreate64BitTable (
     DEBUG ((
       DEBUG_INFO,
       "%a() re-allocate SMBIOS 64-bit table\n",
-      __FUNCTION__
+      __func__
       ));
     if (Smbios30EntryPointStructure->TableAddress != 0) {
       //
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/TcgMorLockDxe.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/TcgMorLockDxe.c
index 88984c31ab..114d0693fe 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/TcgMorLockDxe.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/TcgMorLockDxe.c
@@ -116,7 +116,7 @@ MorLockInitAtEndOfDxe (
   // First, we obviously need to locate the VariablePolicy protocol.
   Status = gBS->LocateProtocol (&gEdkiiVariablePolicyProtocolGuid, NULL, (VOID **)&VariablePolicy);
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a - Could not locate VariablePolicy protocol! %r\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "%a - Could not locate VariablePolicy protocol! %r\n", __func__, Status));
     return;
   }
 
@@ -132,7 +132,7 @@ MorLockInitAtEndOfDxe (
              VARIABLE_POLICY_TYPE_LOCK_NOW
              );
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a - Could not lock variable %s! %r\n", __FUNCTION__, MEMORY_OVERWRITE_REQUEST_CONTROL_LOCK_NAME, Status));
+    DEBUG ((DEBUG_ERROR, "%a - Could not lock variable %s! %r\n", __func__, MEMORY_OVERWRITE_REQUEST_CONTROL_LOCK_NAME, Status));
   }
 
   Status = RegisterBasicVariablePolicy (
@@ -146,7 +146,7 @@ MorLockInitAtEndOfDxe (
              VARIABLE_POLICY_TYPE_LOCK_NOW
              );
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a - Could not lock variable %s! %r\n", __FUNCTION__, MEMORY_OVERWRITE_REQUEST_VARIABLE_NAME, Status));
+    DEBUG ((DEBUG_ERROR, "%a - Could not lock variable %s! %r\n", __func__, MEMORY_OVERWRITE_REQUEST_VARIABLE_NAME, Status));
   }
 
   return;
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/TcgMorLockSmm.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/TcgMorLockSmm.c
index 296afd2ec4..da1105ff07 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/TcgMorLockSmm.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/TcgMorLockSmm.c
@@ -485,7 +485,7 @@ MorLockInitAtEndOfDxe (
     DEBUG ((
       DEBUG_WARN,
       "%a: deleting unexpected / unsupported variable %g:%s\n",
-      __FUNCTION__,
+      __func__,
       &gEfiMemoryOverwriteControlDataGuid,
       MEMORY_OVERWRITE_REQUEST_VARIABLE_NAME
       ));
@@ -521,7 +521,7 @@ MorLockInitAtEndOfDxe (
   }
 
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a - Failed to lock variable %s! %r\n", __FUNCTION__, MEMORY_OVERWRITE_REQUEST_VARIABLE_NAME, Status));
+    DEBUG ((DEBUG_ERROR, "%a - Failed to lock variable %s! %r\n", __func__, MEMORY_OVERWRITE_REQUEST_VARIABLE_NAME, Status));
     ASSERT_EFI_ERROR (Status);
   }
 
@@ -559,7 +559,7 @@ MorLockInitAtEndOfDxe (
   }
 
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a - Failed to lock variable %s! %r\n", __FUNCTION__, MEMORY_OVERWRITE_REQUEST_CONTROL_LOCK_NAME, Status));
+    DEBUG ((DEBUG_ERROR, "%a - Failed to lock variable %s! %r\n", __func__, MEMORY_OVERWRITE_REQUEST_CONTROL_LOCK_NAME, Status));
     ASSERT_EFI_ERROR (Status);
   }
 
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
index 3eb7d935b4..7a1331255b 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
@@ -2770,7 +2770,7 @@ VariableServiceSetVariable (
         DEBUG ((
           DEBUG_ERROR,
           "%a: Failed to set variable '%s' with Guid %g\n",
-          __FUNCTION__,
+          __func__,
           VariableName,
           VendorGuid
           ));
@@ -2792,7 +2792,7 @@ VariableServiceSetVariable (
         DEBUG ((
           DEBUG_ERROR,
           "%a: Failed to set variable '%s' with Guid %g\n",
-          __FUNCTION__,
+          __func__,
           VariableName,
           VendorGuid
           ));
@@ -2814,7 +2814,7 @@ VariableServiceSetVariable (
         DEBUG ((
           DEBUG_ERROR,
           "%a: Failed to set variable '%s' with Guid %g\n",
-          __FUNCTION__,
+          __func__,
           VariableName,
           VendorGuid
           ));
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableLockRequestToLock.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableLockRequestToLock.c
index d849ee9ce2..f6bb7284f0 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableLockRequestToLock.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableLockRequestToLock.c
@@ -48,7 +48,7 @@ VariableLockRequestToLock (
   EFI_STATUS             Status;
   VARIABLE_POLICY_ENTRY  *NewPolicy;
 
-  DEBUG ((DEBUG_WARN, "!!! DEPRECATED INTERFACE !!! %a() will go away soon!\n", __FUNCTION__));
+  DEBUG ((DEBUG_WARN, "!!! DEPRECATED INTERFACE !!! %a() will go away soon!\n", __func__));
   DEBUG ((DEBUG_WARN, "!!! DEPRECATED INTERFACE !!! Please move to use Variable Policy!\n"));
   DEBUG ((DEBUG_WARN, "!!! DEPRECATED INTERFACE !!! Variable: %g %s\n", VendorGuid, VariableName));
 
@@ -85,7 +85,7 @@ VariableLockRequestToLock (
   }
 
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a - Failed to lock variable %s! %r\n", __FUNCTION__, VariableName, Status));
+    DEBUG ((DEBUG_ERROR, "%a - Failed to lock variable %s! %r\n", __func__, VariableName, Status));
   }
 
   if (NewPolicy != NULL) {
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariablePolicySmmDxe.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariablePolicySmmDxe.c
index b2094fbcd6..6151a2ba0b 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariablePolicySmmDxe.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariablePolicySmmDxe.c
@@ -95,7 +95,7 @@ ProtocolDisableVariablePolicy (
   PolicyHeader->Command     = VAR_CHECK_POLICY_COMMAND_DISABLE;
 
   Status = InternalMmCommunicate (CommHeader, &BufferSize);
-  DEBUG ((DEBUG_VERBOSE, "%a - MmCommunication returned %r.\n", __FUNCTION__, Status));
+  DEBUG ((DEBUG_VERBOSE, "%a - MmCommunication returned %r.\n", __func__, Status));
 
   ReleaseLockOnlyAtBootTime (&mMmCommunicationLock);
 
@@ -144,7 +144,7 @@ ProtocolIsVariablePolicyEnabled (
   PolicyHeader->Command     = VAR_CHECK_POLICY_COMMAND_IS_ENABLED;
 
   Status = InternalMmCommunicate (CommHeader, &BufferSize);
-  DEBUG ((DEBUG_VERBOSE, "%a - MmCommunication returned %r.\n", __FUNCTION__, Status));
+  DEBUG ((DEBUG_VERBOSE, "%a - MmCommunication returned %r.\n", __func__, Status));
 
   if (!EFI_ERROR (Status)) {
     Status = PolicyHeader->Result;
@@ -197,7 +197,7 @@ ProtocolRegisterVariablePolicy (
     DEBUG ((
       DEBUG_ERROR,
       "%a - Policy too large for buffer! %r, %d > %d \n",
-      __FUNCTION__,
+      __func__,
       Status,
       RequiredSize,
       mMmCommunicationBufferSize
@@ -222,7 +222,7 @@ ProtocolRegisterVariablePolicy (
   CopyMem (PolicyBuffer, NewPolicy, NewPolicy->Size);
 
   Status = InternalMmCommunicate (CommHeader, &BufferSize);
-  DEBUG ((DEBUG_VERBOSE, "%a - MmCommunication returned %r.\n", __FUNCTION__, Status));
+  DEBUG ((DEBUG_VERBOSE, "%a - MmCommunication returned %r.\n", __func__, Status));
 
   ReleaseLockOnlyAtBootTime (&mMmCommunicationLock);
 
@@ -278,7 +278,7 @@ DumpVariablePolicyHelper (
   CommandParams->PageRequested = PageRequested;
 
   Status = InternalMmCommunicate (CommHeader, &BufferSize);
-  DEBUG ((DEBUG_VERBOSE, "%a - MmCommunication returned %r.\n", __FUNCTION__, Status));
+  DEBUG ((DEBUG_VERBOSE, "%a - MmCommunication returned %r.\n", __func__, Status));
 
   if (!EFI_ERROR (Status)) {
     Status     = PolicyHeader->Result;
@@ -403,7 +403,7 @@ ProtocolLockVariablePolicy (
   PolicyHeader->Command     = VAR_CHECK_POLICY_COMMAND_LOCK;
 
   Status = InternalMmCommunicate (CommHeader, &BufferSize);
-  DEBUG ((DEBUG_VERBOSE, "%a - MmCommunication returned %r.\n", __FUNCTION__, Status));
+  DEBUG ((DEBUG_VERBOSE, "%a - MmCommunication returned %r.\n", __func__, Status));
 
   ReleaseLockOnlyAtBootTime (&mMmCommunicationLock);
 
@@ -500,7 +500,7 @@ VariablePolicySmmDxeMain (
   // Locate the shared comm buffer to use for sending MM commands.
   Status = InitMmCommonCommBuffer (&mMmCommunicationBufferSize, &mMmCommunicationBuffer);
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a - Failed to locate a viable MM comm buffer! %r\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "%a - Failed to locate a viable MM comm buffer! %r\n", __func__, Status));
     ASSERT_EFI_ERROR (Status);
     return Status;
   }
@@ -508,7 +508,7 @@ VariablePolicySmmDxeMain (
   // Locate the MmCommunication protocol.
   Status = gBS->LocateProtocol (&gEfiMmCommunication2ProtocolGuid, NULL, (VOID **)&mMmCommunication);
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a - Failed to locate MmCommunication protocol! %r\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "%a - Failed to locate MmCommunication protocol! %r\n", __func__, Status));
     ASSERT_EFI_ERROR (Status);
     return Status;
   }
@@ -529,7 +529,7 @@ VariablePolicySmmDxeMain (
                   NULL
                   );
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a - Failed to install protocol! %r\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "%a - Failed to install protocol! %r\n", __func__, Status));
     goto Exit;
   } else {
     ProtocolInstalled = TRUE;
@@ -551,7 +551,7 @@ VariablePolicySmmDxeMain (
                   &VirtualAddressChangeEvent
                   );
   if (EFI_ERROR (Status)) {
-    DEBUG ((DEBUG_ERROR, "%a - Failed to create VirtualAddressChange event! %r\n", __FUNCTION__, Status));
+    DEBUG ((DEBUG_ERROR, "%a - Failed to create VirtualAddressChange event! %r\n", __func__, Status));
     goto Exit;
   } else {
     VirtualAddressChangeRegistered = TRUE;