diff --git a/mozilla/expat/xmltok/xmldef.h b/mozilla/expat/xmltok/xmldef.h
index f9edff8a4cb..7ce172ba5fa 100644
--- a/mozilla/expat/xmltok/xmldef.h
+++ b/mozilla/expat/xmltok/xmldef.h
@@ -56,16 +56,18 @@ particular environments. */
  */
 
 #include "nspr.h"
-#define malloc(x) PR_Malloc(x)
-#define realloc(x, y) PR_Realloc((x), (y))
+#define malloc(x) PR_Malloc((size_t)(x))
+#define realloc(x, y) PR_Realloc((x), (size_t)(y))
 #define calloc(x, y) PR_Calloc((x),(y))
 #define free(x) PR_Free(x)
+#define memcpy(x, y, z) memcpy((x), (y), (size_t)(z))
+#define memmove(x, y, z) memmove((x), (y), (size_t)(z))
+#define memcmp(x, y, z) memcmp((x), (y), (size_t)(z))
 
 #if PR_BYTES_PER_INT != 4
 typedef PRInt32 int;
 #endif
 
-
 /* Enable Unicode string processing in expat */
 #define XML_UNICODE
 
diff --git a/mozilla/parser/expat/lib/xmldef.h b/mozilla/parser/expat/lib/xmldef.h
index f9edff8a4cb..7ce172ba5fa 100644
--- a/mozilla/parser/expat/lib/xmldef.h
+++ b/mozilla/parser/expat/lib/xmldef.h
@@ -56,16 +56,18 @@ particular environments. */
  */
 
 #include "nspr.h"
-#define malloc(x) PR_Malloc(x)
-#define realloc(x, y) PR_Realloc((x), (y))
+#define malloc(x) PR_Malloc((size_t)(x))
+#define realloc(x, y) PR_Realloc((x), (size_t)(y))
 #define calloc(x, y) PR_Calloc((x),(y))
 #define free(x) PR_Free(x)
+#define memcpy(x, y, z) memcpy((x), (y), (size_t)(z))
+#define memmove(x, y, z) memmove((x), (y), (size_t)(z))
+#define memcmp(x, y, z) memcmp((x), (y), (size_t)(z))
 
 #if PR_BYTES_PER_INT != 4
 typedef PRInt32 int;
 #endif
 
-
 /* Enable Unicode string processing in expat */
 #define XML_UNICODE