diff --git a/reactos/lib/cmlib/cmtools.c b/reactos/lib/cmlib/cmtools.c
index 41a28e8bdd1..9ea7a55d08e 100644
--- a/reactos/lib/cmlib/cmtools.c
+++ b/reactos/lib/cmlib/cmtools.c
@@ -44,7 +44,7 @@ CmComparePackedNames(
 {
     ULONG i;
 
-    if (NamePacked == TRUE)
+    if (NamePacked)
     {
         PUCHAR PackedName = (PUCHAR)Name;
 
@@ -153,7 +153,7 @@ CmCopyPackedName(
     ASSERT(Name != 0);
     ASSERT(NameLength != 0);
 
-    if (NamePacked == TRUE)
+    if (NamePacked)
     {
         NameLength *= sizeof(WCHAR);
         CharCount = min(BufferLength, NameLength) / sizeof(WCHAR);
diff --git a/reactos/lib/drivers/hidparser/api.c b/reactos/lib/drivers/hidparser/api.c
index fc73ecf71f3..d4eb327a9a4 100644
--- a/reactos/lib/drivers/hidparser/api.c
+++ b/reactos/lib/drivers/hidparser/api.c
@@ -184,7 +184,7 @@ HidParser_GetReportItemTypeCountFromReportType(
         //
         // check item type
         //
-        if (Report->Items[Index].HasData && bData == TRUE)
+        if (Report->Items[Index].HasData && bData)
         {
             //
             // found data item
diff --git a/reactos/lib/drivers/hidparser/hidparser.c b/reactos/lib/drivers/hidparser/hidparser.c
index 25a04c19c9a..ca6be3c94c2 100644
--- a/reactos/lib/drivers/hidparser/hidparser.c
+++ b/reactos/lib/drivers/hidparser/hidparser.c
@@ -139,9 +139,9 @@ HidParser_GetCollectionDescription(
         DeviceDescription->ReportIDs[Index].FeatureLength = HidParser_GetReportLength((PVOID)DeviceDescription->CollectionDesc[Index].PreparsedData, HID_REPORT_TYPE_FEATURE);
 
 
-        DeviceDescription->ReportIDs[Index].InputLength += (HidParser_UsesReportId((PVOID)DeviceDescription->CollectionDesc[Index].PreparsedData, HID_REPORT_TYPE_INPUT) == TRUE ? 1 : 0);
-        DeviceDescription->ReportIDs[Index].OutputLength += (HidParser_UsesReportId((PVOID)DeviceDescription->CollectionDesc[Index].PreparsedData, HID_REPORT_TYPE_OUTPUT) == TRUE ? 1 : 0);
-        DeviceDescription->ReportIDs[Index].FeatureLength += (HidParser_UsesReportId((PVOID)DeviceDescription->CollectionDesc[Index].PreparsedData, HID_REPORT_TYPE_FEATURE) == TRUE ? 1 : 0);
+        DeviceDescription->ReportIDs[Index].InputLength += (HidParser_UsesReportId((PVOID)DeviceDescription->CollectionDesc[Index].PreparsedData, HID_REPORT_TYPE_INPUT) ? 1 : 0);
+        DeviceDescription->ReportIDs[Index].OutputLength += (HidParser_UsesReportId((PVOID)DeviceDescription->CollectionDesc[Index].PreparsedData, HID_REPORT_TYPE_OUTPUT) ? 1 : 0);
+        DeviceDescription->ReportIDs[Index].FeatureLength += (HidParser_UsesReportId((PVOID)DeviceDescription->CollectionDesc[Index].PreparsedData, HID_REPORT_TYPE_FEATURE) ? 1 : 0);
 
 
         //
diff --git a/reactos/lib/drivers/hidparser/parser.c b/reactos/lib/drivers/hidparser/parser.c
index 5912843442c..c314a96fe9b 100644
--- a/reactos/lib/drivers/hidparser/parser.c
+++ b/reactos/lib/drivers/hidparser/parser.c
@@ -570,7 +570,7 @@ HidParser_InitReportItem(
     ReportItem->BitCount = GlobalItemState->ReportSize;
     ReportItem->HasData = (ItemData->DataConstant == FALSE);
     ReportItem->Array = (ItemData->ArrayVariable == 0);
-    ReportItem->Relative = (ItemData->Relative == TRUE);
+    ReportItem->Relative = (ItemData->Relative != FALSE);
     ReportItem->Minimum = LogicalMinimum;
     ReportItem->Maximum = LogicalMaximum;
     ReportItem->UsageMinimum = UsageMinimum;
diff --git a/reactos/lib/drivers/ip/network/routines.c b/reactos/lib/drivers/ip/network/routines.c
index 48af20b210d..ac7fce520aa 100644
--- a/reactos/lib/drivers/ip/network/routines.c
+++ b/reactos/lib/drivers/ip/network/routines.c
@@ -63,8 +63,9 @@ VOID DisplayIPPacket(
     UINT Length;
     PCHAR CharBuffer;
 
-    if ((DbgQueryDebugFilterState(DPFLTR_TCPIP_ID, DEBUG_PBUFFER | DPFLTR_MASK) != TRUE) ||
-        (DbgQueryDebugFilterState(DPFLTR_TCPIP_ID, DEBUG_IP | DPFLTR_MASK) != TRUE)) {
+    /* DbgQueryDebugFilterState returns (NTSTATUS)TRUE, (NTSTATUS)FALSE or a failure status code */
+    if ((DbgQueryDebugFilterState(DPFLTR_TCPIP_ID, DEBUG_PBUFFER | DPFLTR_MASK) != (NTSTATUS)TRUE) ||
+        (DbgQueryDebugFilterState(DPFLTR_TCPIP_ID, DEBUG_IP | DPFLTR_MASK) != (NTSTATUS)TRUE)) {
         return;
     }
 
diff --git a/reactos/lib/drivers/sound/mmebuddy/mmewrap.c b/reactos/lib/drivers/sound/mmebuddy/mmewrap.c
index bf850d24257..186b69a0c5e 100644
--- a/reactos/lib/drivers/sound/mmebuddy/mmewrap.c
+++ b/reactos/lib/drivers/sound/mmebuddy/mmewrap.c
@@ -57,7 +57,7 @@ MmeSetState(
         /* Store audio stream pause state */
         SoundDeviceInstance->bPaused = !bStart;
 
-        if (SoundDeviceInstance->bPaused == FALSE && OldState == TRUE)
+        if (SoundDeviceInstance->bPaused == FALSE && OldState)
         {
             InitiateSoundStreaming(SoundDeviceInstance);
         }
diff --git a/reactos/lib/drivers/sound/mmixer/controls.c b/reactos/lib/drivers/sound/mmixer/controls.c
index e00fca399cd..04fe001dc0e 100644
--- a/reactos/lib/drivers/sound/mmixer/controls.c
+++ b/reactos/lib/drivers/sound/mmixer/controls.c
@@ -1586,7 +1586,7 @@ MMixerHandleAlternativeMixers(
         MMixerIsTopologyPinReserved(Topology, Index, &Reserved);
 
         /* check if it has already been reserved */
-        if (Reserved == TRUE)
+        if (Reserved)
         {
             /* pin has already been reserved */
             continue;
diff --git a/reactos/lib/rtl/debug.c b/reactos/lib/rtl/debug.c
index 25ccbcfb718..88a143a13c4 100644
--- a/reactos/lib/rtl/debug.c
+++ b/reactos/lib/rtl/debug.c
@@ -64,7 +64,7 @@ vDbgPrintExWithPrefixInternal(IN PCCH Prefix,
 
     /* Check if we should print it or not */
     if ((ComponentId != MAXULONG) &&
-        (NtQueryDebugFilterState(ComponentId, Level)) != TRUE)
+        (NtQueryDebugFilterState(ComponentId, Level)) != (NTSTATUS)TRUE)
     {
         /* This message is masked */
         return STATUS_SUCCESS;
diff --git a/reactos/lib/rtl/env.c b/reactos/lib/rtl/env.c
index 71e8efb89f1..2135c5a6fd3 100644
--- a/reactos/lib/rtl/env.c
+++ b/reactos/lib/rtl/env.c
@@ -535,7 +535,7 @@ RtlQueryEnvironmentVariable_U(PWSTR Environment,
    }
 
    Value->Length = 0;
-   if (SysEnvUsed == TRUE)
+   if (SysEnvUsed)
       RtlAcquirePebLock();
 
    wcs = Environment;
@@ -573,7 +573,7 @@ RtlQueryEnvironmentVariable_U(PWSTR Environment,
                Status = STATUS_BUFFER_TOO_SMALL;
             }
 
-            if (SysEnvUsed == TRUE)
+            if (SysEnvUsed)
                RtlReleasePebLock();
 
             return(Status);
@@ -582,7 +582,7 @@ RtlQueryEnvironmentVariable_U(PWSTR Environment,
       wcs++;
    }
 
-   if (SysEnvUsed == TRUE)
+   if (SysEnvUsed)
       RtlReleasePebLock();
 
    DPRINT("Return STATUS_VARIABLE_NOT_FOUND: %wZ\n", Name);
diff --git a/reactos/lib/rtl/resource.c b/reactos/lib/rtl/resource.c
index 40f6970ea79..e60e57a1d04 100644
--- a/reactos/lib/rtl/resource.c
+++ b/reactos/lib/rtl/resource.c
@@ -105,7 +105,7 @@ start:
             goto done;
         }
 wait:
-        if (Wait == TRUE)
+        if (Wait)
         {
             Resource->ExclusiveWaiters++;
 
@@ -120,10 +120,10 @@ wait:
     }
     else  /* one or more shared locks are in progress */
     {
-        if (Wait == TRUE)
+        if (Wait)
             goto wait;
     }
-    if (retVal == TRUE)
+    if (retVal)
         Resource->OwningThread = NtCurrentTeb()->ClientId.UniqueThread;
 done:
     RtlLeaveCriticalSection(&Resource->Lock);
@@ -154,7 +154,7 @@ start:
             goto done;
         }
 
-        if (Wait == TRUE)
+        if (Wait)
         {
             Resource->SharedWaiters++;
             RtlLeaveCriticalSection(&Resource->Lock);
diff --git a/reactos/lib/rtl/time.c b/reactos/lib/rtl/time.c
index fc587ed28a8..e37dd13c7c6 100644
--- a/reactos/lib/rtl/time.c
+++ b/reactos/lib/rtl/time.c
@@ -106,7 +106,7 @@ RtlCutoverTimeToSystemTime(IN PTIME_FIELDS CutoverTimeFields,
     {
         /* Compute the cutover time of the first day of the current month */
         AdjustedTimeFields.Year = CurrentTimeFields.Year;
-        if (NextYearsCutover == TRUE)
+        if (NextYearsCutover)
             AdjustedTimeFields.Year++;
 
         AdjustedTimeFields.Month = CutoverTimeFields->Month;
@@ -146,8 +146,8 @@ RtlCutoverTimeToSystemTime(IN PTIME_FIELDS CutoverTimeFields,
         if (!RtlTimeFieldsToTime(&AdjustedTimeFields, &CutoverSystemTime))
             return FALSE;
 
-        if (ThisYearsCutoverOnly == TRUE ||
-            NextYearsCutover == TRUE ||
+        if (ThisYearsCutoverOnly ||
+            NextYearsCutover ||
             CutoverSystemTime.QuadPart >= CurrentTime->QuadPart)
         {
             break;
diff --git a/reactos/lib/rtl/unicode.c b/reactos/lib/rtl/unicode.c
index 3d0efaff55c..321bb417d01 100644
--- a/reactos/lib/rtl/unicode.c
+++ b/reactos/lib/rtl/unicode.c
@@ -1809,7 +1809,7 @@ RtlUpcaseUnicodeString(
 
     PAGED_CODE_RTL();
 
-    if (AllocateDestinationString == TRUE)
+    if (AllocateDestinationString)
     {
         UniDest->MaximumLength = UniSource->Length;
         UniDest->Buffer = RtlpAllocateStringMemory(UniDest->MaximumLength, TAG_USTR);
@@ -2620,7 +2620,7 @@ RtlDnsHostNameToComputerName(PUNICODE_STRING ComputerName, PUNICODE_STRING DnsHo
             ComputerNameOem.Length = (USHORT)ComputerNameOemNLength;
             ComputerNameOem.MaximumLength = (USHORT)(MAX_COMPUTERNAME_LENGTH + 1);
 
-            if (RtlpDidUnicodeToOemWork(DnsHostName, &ComputerNameOem) == TRUE)
+            if (RtlpDidUnicodeToOemWork(DnsHostName, &ComputerNameOem))
             {
                 /* no unmapped character so convert it back to an unicode string */
                 Status = RtlOemStringToUnicodeString(ComputerName,
diff --git a/reactos/lib/sdk/crt/misc/lock.c b/reactos/lib/sdk/crt/misc/lock.c
index 4351b07be6a..b15ef47ac7a 100644
--- a/reactos/lib/sdk/crt/misc/lock.c
+++ b/reactos/lib/sdk/crt/misc/lock.c
@@ -83,7 +83,7 @@ void msvcrt_free_mt_locks(void)
   /* Uninitialize the table */
   for( i=0; i < _TOTAL_LOCKS; i++ )
   {
-    if( lock_table[ i ].bInit == TRUE )
+    if( lock_table[ i ].bInit )
     {
       msvcrt_uninitialize_mlock( i );
     }