diff --git a/packages/libxml/src/tree.inc b/packages/libxml/src/tree.inc
index ff034a9b30..aaf1a988e8 100644
--- a/packages/libxml/src/tree.inc
+++ b/packages/libxml/src/tree.inc
@@ -562,8 +562,8 @@ procedure xmlSetBufferAllocationScheme(scheme: xmlBufferAllocationScheme); XMLCA
 function xmlGetBufferAllocationScheme: xmlBufferAllocationScheme; XMLCALL; XMLPUBFUN;
 
 function xmlBufferCreate: xmlBufferPtr; XMLCALL; XMLPUBFUN;
-function xmlBufferCreateSize(size: size_t): xmlBufferPtr; XMLCALL; XMLPUBFUN;
-function xmlBufferCreateStatic(mem: pointer; size: size_t): xmlBufferPtr; XMLCALL; XMLPUBFUN;
+function xmlBufferCreateSize(size: csize_t): xmlBufferPtr; XMLCALL; XMLPUBFUN;
+function xmlBufferCreateStatic(mem: pointer; size: csize_t): xmlBufferPtr; XMLCALL; XMLPUBFUN;
 function xmlBufferResize(buf: xmlBufferPtr; size: cuint): cint; XMLCALL; XMLPUBFUN;
 procedure xmlBufferFree(buf: xmlBufferPtr); XMLCALL; XMLPUBFUN;
 procedure xmlBufferDump(fp: PFILE; buf: xmlBufferPtr); XMLCALL; XMLPUBFUN;
diff --git a/packages/libxml/src/xml2.pas b/packages/libxml/src/xml2.pas
index 3f2ad54548..5a6d613c92 100644
--- a/packages/libxml/src/xml2.pas
+++ b/packages/libxml/src/xml2.pas
@@ -47,11 +47,6 @@ const
 {$i xmlexports.inc}
 {$i xmlversion.inc}
 
-{$IFDEF WINDOWS}
-type
-  size_t = culong;
-{$ENDIF}
-
 type
   PFILE = pointer;
   va_list = pointer;
diff --git a/packages/libxml/src/xmlmemory.inc b/packages/libxml/src/xmlmemory.inc
index df5b91f75c..8a8746c686 100644
--- a/packages/libxml/src/xmlmemory.inc
+++ b/packages/libxml/src/xmlmemory.inc
@@ -54,7 +54,7 @@
  *
  * Returns a pointer to the newly allocated block or NULL in case of error.
  *)
-  xmlMallocFunc = function(size: size_t): pointer; XMLCALL;
+  xmlMallocFunc = function(size: csize_t): pointer; XMLCALL;
 
 (**
  * xmlReallocFunc:
@@ -65,7 +65,7 @@
  *
  * Returns a pointer to the newly reallocated block or NULL in case of error.
  *)
-  xmlReallocFunc = function(mem: pointer; size: size_t): pointer; XMLCALL;
+  xmlReallocFunc = function(mem: pointer; size: csize_t): pointer; XMLCALL;
 
 (**
  * xmlStrdupFunc:
@@ -116,14 +116,14 @@ function xmlMemBlocks(): cint; XMLCALL; XMLPUBFUN;
 procedure xmlMemDisplay(fp: PFILE); XMLCALL; XMLPUBFUN;
 procedure xmlMemShow(fp: PFILE; nr: cint); XMLCALL; XMLPUBFUN;
 procedure xmlMemoryDump(); XMLCALL; XMLPUBFUN;
-function xmlMemMalloc(size: size_t): pointer; XMLCALL; XMLPUBFUN;
-function xmlMemRealloc(ptr: pointer; size: size_t): pointer; XMLCALL; XMLPUBFUN;
+function xmlMemMalloc(size: csize_t): pointer; XMLCALL; XMLPUBFUN;
+function xmlMemRealloc(ptr: pointer; size: csize_t): pointer; XMLCALL; XMLPUBFUN;
 procedure xmlMemFree(ptr: pointer); XMLCALL; XMLPUBFUN;
 function xmlMemoryStrdup(str: pchar): pchar; XMLCALL; XMLPUBFUN;
 
-function xmlMallocLoc(size: size_t; _file: pchar; line: cint): pointer; XMLCALL; XMLPUBFUN;
-function xmlReallocLoc(ptr: pointer; size: size_t; _file: pchar; line: cint): pointer; XMLCALL; XMLPUBFUN;
-function xmlMallocAtomicLoc(size: size_t; _file: pchar; line: cint): pointer; XMLCALL; XMLPUBFUN;
+function xmlMallocLoc(size: csize_t; _file: pchar; line: cint): pointer; XMLCALL; XMLPUBFUN;
+function xmlReallocLoc(ptr: pointer; size: csize_t; _file: pchar; line: cint): pointer; XMLCALL; XMLPUBFUN;
+function xmlMallocAtomicLoc(size: csize_t; _file: pchar; line: cint): pointer; XMLCALL; XMLPUBFUN;
 function xmlMemStrdupLoc(str: pchar; _file: pchar; line: cint): pchar; XMLCALL; XMLPUBFUN;
 
 {$IFDEF DEBUG_MEMORY_LOCATION}