diff --git a/H/TermExt.h b/H/TermExt.h
index ddd750e49..ec8c08dd4 100644
--- a/H/TermExt.h
+++ b/H/TermExt.h
@@ -148,8 +148,8 @@ exts;
 
 #endif
 
-#ifdef YAP_H
 
+#ifdef YAP_H
 /* make sure that these data structures are the first thing to be allocated
    in the heap when we start the system */
 #ifdef THREADS
@@ -175,7 +175,9 @@ typedef struct special_functors_struct
 special_functors;
 #endif
 
-inline EXTERN Float STD_PROTO (CpFloatUnaligned, (CELL *));
+#endif /* YAP_H */
+
+inline extern Float CpFloatUnaligned(CELL *ptr);
 
 #if SIZEOF_DOUBLE == SIZEOF_LONG_INT
 
@@ -214,7 +216,7 @@ CpFloatUnaligned(CELL *ptr)
 
 #if SIZEOF_DOUBLE == 2*SIZEOF_LONG_INT
 
-inline EXTERN void STD_PROTO (AlignGlobalForDouble, ( USES_REGS1 ));
+inline extern void AlignGlobalForDouble( USES_REGS1 );
 
 #define DOUBLE_ALIGNED(ADDR) ((CELL)(ADDR) & 0x4)
 
@@ -272,13 +274,16 @@ FloatOfTerm (Term t)
 #endif
 #endif
 
-Term STD_PROTO (Yap_MkBlobStringTerm, (const char *, size_t len));
-Term STD_PROTO (Yap_MkBlobWideStringTerm, (const wchar_t *, size_t len));
-char *STD_PROTO (Yap_BlobStringOfTerm, (Term));
-wchar_t *STD_PROTO (Yap_BlobWideStringOfTerm, (Term));
-char *STD_PROTO (Yap_BlobStringOfTermAndLength, (Term, size_t *));
+#ifndef YAP_H
+#include <stddef.h>
+#endif
+
+Term Yap_MkBlobStringTerm(const char *, size_t len);
+Term Yap_MkBlobWideStringTerm(const wchar_t *, size_t len);
+char *Yap_BlobStringOfTerm(Term);
+wchar_t *Yap_BlobWideStringOfTerm(Term);
+char *Yap_BlobStringOfTermAndLength(Term, size_t *);
 
-#endif /* YAP_NOT_INSTALLED */
 
 
 inline EXTERN int IsFloatTerm (Term);
@@ -294,7 +299,6 @@ IsFloatTerm (Term t)
 
 /* extern Functor FunctorLongInt; */
 
-#ifdef YAP_H
 inline EXTERN Term MkLongIntTerm (Int);
 
 inline EXTERN Term
@@ -308,7 +312,6 @@ MkLongIntTerm (Int i)
   return AbsAppl(H - 3);
 }
 
-#endif
 
 inline EXTERN Int LongIntOfTerm (Term t);
 
diff --git a/H/Yap.h b/H/Yap.h
index 5ccf5903b..768906d2d 100755
--- a/H/Yap.h
+++ b/H/Yap.h
@@ -818,6 +818,12 @@ extern struct worker_local Yap_local;
 #include "dlocals.h"
 
 
+/*************************************************************************************************
+                                       unification support
+*************************************************************************************************/
+
+#include "YapCompoundTerm.h"
+
 /*************************************************************************************************
                                        unification routines
 *************************************************************************************************/
@@ -831,69 +837,6 @@ extern struct worker_local Yap_local;
 
 
 
-/*************************************************************************************************
-                           High level macros to access arguments
-*************************************************************************************************/
-
-inline EXTERN Term ArgOfTerm (int i, Term t);
-
-inline EXTERN Term
-ArgOfTerm (int i, Term t)
-{
-  return (Term) (Derefa (RepAppl (t) + (i)));
-}
-
-
-
-inline EXTERN Term HeadOfTerm (Term);
-
-inline EXTERN Term
-HeadOfTerm (Term t)
-{
-  return (Term) (Derefa (RepPair (t)));
-}
-
-
-
-inline EXTERN Term TailOfTerm (Term);
-
-inline EXTERN Term
-TailOfTerm (Term t)
-{
-  return (Term) (Derefa (RepPair (t) + 1));
-}
-
-
-
-
-inline EXTERN Term ArgOfTermCell (int i, Term t);
-
-inline EXTERN Term
-ArgOfTermCell (int i, Term t)
-{
-  return (Term) ((CELL) (RepAppl (t) + (i)));
-}
-
-
-
-inline EXTERN Term HeadOfTermCell (Term);
-
-inline EXTERN Term
-HeadOfTermCell (Term t)
-{
-  return (Term) ((CELL) (RepPair (t)));
-}
-
-
-
-inline EXTERN Term TailOfTermCell (Term);
-
-inline EXTERN Term
-TailOfTermCell (Term t)
-{
-  return (Term) ((CELL) (RepPair (t) + 1));
-}
-
 
 /*************************************************************************************************
                                            slots
diff --git a/H/YapCompoundTerm.h b/H/YapCompoundTerm.h
new file mode 100644
index 000000000..e8b1d3be1
--- /dev/null
+++ b/H/YapCompoundTerm.h
@@ -0,0 +1,115 @@
+/*************************************************************************
+*									 *
+*	 YAP Prolog 	%W% %G% 					 *
+*	Yap Prolog was developed at NCCUP - Universidade do Porto	 *
+*									 *
+* Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-2012	 *
+*									 *
+**************************************************************************
+*									 *
+* File:		YapCompounTerm.h					 *
+* mods:									 *
+* comments:	main header file for YAP				 *
+* version:      $Id: Yap.h,v 1.38 2008-06-18 10:02:27 vsc Exp $	 *
+*************************************************************************/
+
+/*************************************************************************************************
+                           High level macros to access arguments
+*************************************************************************************************/
+
+#ifndef YAPCOMPOUNDTERM_H
+
+#define YAPCOMPOUNDTERM_H 1
+
+EXTERN Int Yap_unify(Term a,Term b);
+
+EXTERN inline Term Deref(Term a);
+
+EXTERN inline Term Deref(Term a)
+{
+   while(IsVarTerm(a)) {
+	Term *b = (Term *) a;
+	a = *b;
+	if(a==((Term) b)) return a;
+   }
+   return(a);
+}
+
+EXTERN inline Term Derefa(CELL *b);
+
+EXTERN inline Term
+Derefa(CELL *b)
+{
+  Term a = *b;
+ restart:
+  if (!IsVarTerm(a)) {
+    return(a);
+  } else if (a == (CELL)b) {
+    return(a);
+  } else {
+    b = (CELL *)a;
+    a = *b;
+    goto restart;
+  }
+}
+
+inline EXTERN Term ArgOfTerm (int i, Term t);
+
+inline EXTERN Term
+ArgOfTerm (int i, Term t)
+{
+  return (Term) (Derefa (RepAppl (t) + (i)));
+}
+
+
+
+inline EXTERN Term HeadOfTerm (Term);
+
+inline EXTERN Term
+HeadOfTerm (Term t)
+{
+  return (Term) (Derefa (RepPair (t)));
+}
+
+
+
+inline EXTERN Term TailOfTerm (Term);
+
+inline EXTERN Term
+TailOfTerm (Term t)
+{
+  return (Term) (Derefa (RepPair (t) + 1));
+}
+
+
+
+
+inline EXTERN Term ArgOfTermCell (int i, Term t);
+
+inline EXTERN Term
+ArgOfTermCell (int i, Term t)
+{
+  return (Term) ((CELL) (RepAppl (t) + (i)));
+}
+
+
+
+inline EXTERN Term HeadOfTermCell (Term);
+
+inline EXTERN Term
+HeadOfTermCell (Term t)
+{
+  return (Term) ((CELL) (RepPair (t)));
+}
+
+
+
+inline EXTERN Term TailOfTermCell (Term);
+
+inline EXTERN Term
+TailOfTermCell (Term t)
+{
+  return (Term) ((CELL) (RepPair (t) + 1));
+}
+
+#endif /* YAPCOMPOUNDTERM_H */
diff --git a/H/YapTags.h b/H/YapTags.h
index 3de5c6c25..c8fbbab42 100644
--- a/H/YapTags.h
+++ b/H/YapTags.h
@@ -184,8 +184,6 @@ IsUnboundVar (Term * t)
 
 #else
 
-#ifdef YAP_H
-
 inline EXTERN Term MkVarTerm__ ( USES_REGS1 );
 
 inline EXTERN Term
@@ -194,8 +192,6 @@ MkVarTerm__ ( USES_REGS1 )
   return (Term) ((*H = (CELL) H, H++));
 }
 
-#endif
-
 
 inline EXTERN int IsUnboundVar (Term *);
 
@@ -316,8 +312,7 @@ IsIntTerm (Term t)
 }
 
 
-#ifdef YAP_H
-EXTERN inline Term STD_PROTO (MkPairTerm__, (Term, Term CACHE_TYPE) );
+EXTERN inline Term MkPairTerm__(Term head, Term  tail CACHE_TYPE );
 
 EXTERN inline Term
 MkPairTerm__ (Term head, Term tail USES_REGS)
@@ -330,7 +325,6 @@ MkPairTerm__ (Term head, Term tail USES_REGS)
   return (AbsPair (p));
 }
 
-#endif
 
 
 /* Needed to handle numbers:
@@ -395,4 +389,6 @@ IntegerOfTerm (Term t)
   return (Int) (IsIntTerm (t) ? IntOfTerm (t) : LongIntOfTerm (t));
 }
 
+#ifndef YAP_H
 
+#endif
diff --git a/H/YapTerm.h b/H/YapTerm.h
index 40f9a04f0..de0ec8770 100644
--- a/H/YapTerm.h
+++ b/H/YapTerm.h
@@ -18,6 +18,10 @@
 
 typedef void *Functor;
 typedef void *Atom;
+
+#define CACHE_TYPE
+#define CACHE_TYPE1 void
+
 #endif
 
 #ifndef EXTERN
@@ -134,3 +138,4 @@ typedef unsigned long int YAP_ULONG_LONG;
 
 #define	Unsigned(V)	((CELL) (V))
 #define	Signed(V)	((Int) (V))
+
diff --git a/H/amiops.h b/H/amiops.h
index f6a8e62de..0b14c43e5 100644
--- a/H/amiops.h
+++ b/H/amiops.h
@@ -87,35 +87,6 @@ Dereferencing macros
 
 #endif /* UNIQUE_TAG_FOR_PAIRS */
 
-EXTERN Term STD_PROTO(Deref,(Term));
-EXTERN Term STD_PROTO(Derefa,(CELL *));
-
-EXTERN inline Term Deref(Term a)
-{
-   while(IsVarTerm(a)) {
-	Term *b = (Term *) a;
-	a = *b;
-	if(a==((Term) b)) return a;
-   }
-   return(a);
-}
-
-EXTERN inline Term
-Derefa(CELL *b)
-{
-  Term a = *b;
- restart:
-  if (!IsVarTerm(a)) {
-    return(a);
-  } else if (a == (CELL)b) {
-    return(a);
-  } else {
-    b = (CELL *)a;
-    a = *b;
-    goto restart;
-  }
-}
-
 /************************************************************
 
 TRAIL VARIABLE
@@ -309,8 +280,6 @@ Unification Routines
 
 *************************************************************/
 
-EXTERN Int STD_PROTO(Yap_unify,(Term,Term));
-
 inline EXTERN void STD_PROTO(reset_trail,(tr_fr_ptr));
 
 inline EXTERN void
diff --git a/Makefile.in b/Makefile.in
index a15e19674..0866f07a6 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -122,8 +122,9 @@ INTERFACE_HEADERS = \
 	$(srcdir)/H/Tags_32LowTag.h \
 	$(srcdir)/H/Tags_64bits.h \
 	$(srcdir)/H/Tags_24bits.h \
-	$(srcdir)/H/YapTerm.h \
+	$(srcdir)/H/YapCompoundTerm.h \
 	$(srcdir)/include/YapRegs.h \
+	$(srcdir)/H/YapTerm.h \
 	$(srcdir)/library/dialect/bprolog/fli/bprolog.h \
 	$(srcdir)/os/SWI-Stream.h
 
@@ -409,7 +410,9 @@ all: parms.h startup.yss @ENABLE_WINCONSOLE@ pl-yap@EXEC_SUFFIX@
 
 Makefile: $(srcdir)/Makefile.in
 
-$(srcdir)/H/Yap.h: config.h YapTermConfig.h $(srcdir)/H/YapTags.h
+$(srcdir)/H/Yap.h: config.h YapTermConfig.h \
+		$(srcdir)/H/YapTags.h \
+		$(srcdir)/H/YapCompoundTerm.h
 
 config.h:	parms.h
 
diff --git a/config.h.in b/config.h.in
index 388312e6c..0cce26ee2 100644
--- a/config.h.in
+++ b/config.h.in
@@ -1,4 +1,8 @@
 
+#ifndef YAP_CONFIG_H
+
+#define YAP_CONFIG_H
+
 #include "parms.h"
 
 /* are dynamic arrays supported? */
@@ -347,5 +351,4 @@
 
 #undef MAX_THREADS
 
-
-
+#endif /* YAP_CONFIG_H */
\ No newline at end of file
diff --git a/packages/prism/src/c/core/bpx.h b/packages/prism/src/c/core/bpx.h
index f15f36704..5b128ea10 100644
--- a/packages/prism/src/c/core/bpx.h
+++ b/packages/prism/src/c/core/bpx.h
@@ -9,8 +9,8 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <YapTerm.h>
-#include <YapTags.h>
 #include <YapRegs.h>
+#include <YapTags.h>
 
 typedef void *SYM_REC_PTR;