diff --git a/HashLib/src/Crypto/Blake2BParams/HlpBlake2BParams.pas b/HashLib/src/Crypto/Blake2BParams/HlpBlake2BParams.pas
index 369ee58..419e04a 100644
--- a/HashLib/src/Crypto/Blake2BParams/HlpBlake2BParams.pas
+++ b/HashLib/src/Crypto/Blake2BParams/HlpBlake2BParams.pas
@@ -97,7 +97,7 @@   TBlake2BTreeConfig = class sealed(TInterfacedObject, IBlake2BTreeConfig)
     procedure ValidateInnerHashSize(AInnerHashSize: Byte); inline;
     procedure ValidateMaxDepth(AMaxDepth: Byte); inline;
     procedure ValidateNodeDepth(ANodeDepth: Byte); inline;
-    procedure ValidateNodeOffset(ANodeOffset: UInt64); inline;
+    procedure ValidateNodeOffset(ANodeOffset: UInt64);
 
     function GetFanOut: Byte; inline;
     procedure SetFanOut(AValue: Byte); inline;
@@ -342,9 +342,10 @@ procedure TBlake2BTreeConfig.ValidateNodeDepth(ANodeDepth: Byte);
 end;
 
 procedure TBlake2BTreeConfig.ValidateNodeOffset(ANodeOffset: UInt64);
+const
+  MaxNodeOffset: UInt64 = $FFFFFFFFFFFFFFFF; // (2^64) - 1
 begin
-  // ANodeOffset > ((2^64) - 1)
-  if ANodeOffset > System.High(UInt64) then
+  if ANodeOffset > MaxNodeOffset then
   begin
     raise EArgumentInvalidHashLibException.CreateRes
       (@SInvalidNodeOffsetParameter);
diff --git a/HashLib/src/Include/HashLib.inc b/HashLib/src/Include/HashLib.inc
index 6c47f0b..d0a32d1 100644
--- a/HashLib/src/Include/HashLib.inc
+++ b/HashLib/src/Include/HashLib.inc
@@ -21,6 +21,13 @@
     {$MESSAGE ERROR 'This Library requires Delphi 2010 or higher.'}
   {$IFEND}
 
+  // Silence H2586 (legacy $IFEND) on XE4+ where $ENDIF can also close $IF.
+  // The $LEGACYIFEND directive itself was introduced in XE4 (25.0), so the
+  // guard is necessary to keep Delphi 2010 / XE / XE2 / XE3 compiling.
+  {$IF CompilerVersion >= 25.0}
+    {$LEGACYIFEND ON}
+  {$IFEND}
+
   {$DEFINE DELPHI}
 
   {$DEFINITIONINFO ON} // Enable code browsing (Ctrl+Click)
diff --git a/HashLib/src/Utils/HlpArmHwCapProvider.pas b/HashLib/src/Utils/HlpArmHwCapProvider.pas
index f4e73c7..3d269d0 100644
--- a/HashLib/src/Utils/HlpArmHwCapProvider.pas
+++ b/HashLib/src/Utils/HlpArmHwCapProvider.pas
@@ -139,12 +139,17 @@ implementation
 
 class procedure TArmHwCapProvider.ResolveDynamicImports();
 var
-  LHandle: Pointer;
+  LHandle: NativeUInt;
 begin
   FGetAuxVal := nil;
 
+{$IFDEF FPC}
+  LHandle := NativeUInt(dlopen(nil, RTLD_NOW));
+{$ELSE}
   LHandle := dlopen(nil, RTLD_NOW);
-  if LHandle = nil then
+{$ENDIF}
+
+  if LHandle = 0 then
     Exit;
 
   try
@@ -179,12 +184,17 @@ class function TArmHwCapProvider.GetHwCap2(): UInt64;
 
 class procedure TArmHwCapProvider.ResolveDynamicImports();
 var
-  LHandle: Pointer;
+  LHandle: NativeUInt;
 begin
   FElfAuxInfo := nil;
 
+{$IFDEF FPC}
+  LHandle := NativeUInt(dlopen(nil, RTLD_NOW));
+{$ELSE}
   LHandle := dlopen(nil, RTLD_NOW);
-  if LHandle = nil then
+{$ENDIF}
+
+  if LHandle = 0 then
     Exit;
 
   try