diff --git a/C/cdmgr.c b/C/cdmgr.c
index 8b9fd55cb..68d5130a0 100644
--- a/C/cdmgr.c
+++ b/C/cdmgr.c
@@ -3097,7 +3097,7 @@ void Yap_HidePred(PredEntry *pe) {
   if (pe->NextOfPE) {
     UInt hash = PRED_HASH(pe->FunctorOfPred, CurrentModule, PredHashTableSize);
     READ_LOCK(PredHashRWLock);
-    PredEntry *p, **op = PredHash+hash;
+    PredEntry *p, **op = PredHash + hash;
     p = *op;
 
     while (p) {
@@ -3144,7 +3144,7 @@ void Yap_HidePred(PredEntry *pe) {
       op = &p->NextPredOfModule;
       p = p->NextPredOfModule;
     }
-pe->NextPredOfModule = NULL;
+    pe->NextPredOfModule = NULL;
   }
 }
 
@@ -3168,16 +3168,15 @@ stash_predicate(USES_REGS1) {
     /*
     char ns[1024];
       const char *s = (pe->ModuleOfPred == PROLOG_MODULE ?
-		     "__prolog__stash__" :
-		     snprintf(sn,1023,"__%s__".RepAtom(AtomOfTerm( pe->ModuleOfPred ))));
-		     pe->ModuleOfPred = MkAtomTerm(Yap_LookupAtom(s));
+                     "__prolog__stash__" :
+                     snprintf(sn,1023,"__%s__".RepAtom(AtomOfTerm(
+    pe->ModuleOfPred )))); pe->ModuleOfPred = MkAtomTerm(Yap_LookupAtom(s));
     */
     return true;
   } else
     return false;
 }
 
-
 static Int /* $hidden_predicate(P) */
 hidden_predicate(USES_REGS1) {
   PredEntry *pe =
diff --git a/CMakeLists.txt b/CMakeLists.txt
old mode 100644
new mode 100755
index 2e62ef230..6b11bf0f0
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -334,9 +334,14 @@ find_package(GMP)
 list(APPEND YAP_SYSTEM_OPTIONS big_numbers)
 
 
+
 if (GMP_FOUND)
     #config.h needs this (TODO: change in code latter)
     include_directories(${GMP_INCLUDE_DIRS})
+        check_include_file(gmp.h HAVE_GMP_H)
+        check_include_file_cxx(gmpxx.h HAVE_GMPXX_H)
+
+
 endif (GMP_FOUND)
 
     option(WITH_READLINE "use readline or libedit" ON)
@@ -416,7 +421,7 @@ set(DEF_TRAILSPACE 0)
 set_property(DIRECTORY APPEND PROPERTY COMPILE_DEFINITIONS DEPTH_LIMIT=1;COROUTINING=1;RATIONAL_TREES=1)
 
 # inform we are compiling YAP
-set_property(DIRECTORY APPEND PROPERTY COMPILE_DEFINITIONS "_YAP_NOT_INSTALLED_=1;HAVE_CONFIG_H=1;_GNU_SOURCE")
+set_property(DIRECTORY APPEND PROPERTY COMPILE_DEFINITIONS "_YAP_NOT_INSTALLED_=1;HAVE_CONFIG_H=1;_GNU_SOURCE=1")
 
 # Compilation model
 #  target_compile_definitions(libYap PUBLIC  _XOPEN_SOURCE=700 )
diff --git a/CXX/yapi.hh b/CXX/yapi.hh
old mode 100644
new mode 100755
index ba6ec0f16..794e5af61
--- a/CXX/yapi.hh
+++ b/CXX/yapi.hh
@@ -8,11 +8,20 @@
 
 #define YAP_CPP_INTERFACE 1
 
-#include <gmpxx.h>
 #include <iostream>
 #include <string>
 #include <vector>
 
+extern "C"{
+#include "config.h"
+}
+
+#if HAVE_GMPXX_H
+#include <gmpxx.h>
+#elif HAVE_GMP_H
+#include <gmp.h>
+#endif
+
 /*!
  *
  *   @ingroup fli_c_cxx
diff --git a/H/TermExt.h b/H/TermExt.h
index cd2487948..d6ffa0f79 100755
--- a/H/TermExt.h
+++ b/H/TermExt.h
@@ -388,26 +388,6 @@ INLINE_ONLY bool IsStringTerm(Term t) {
 
 #include <stdio.h>
 
-#if !defined(__cplusplus)
-#include <gmp.h>
-#endif
-
-#else
-
-typedef UInt mp_limb_t;
-
-typedef struct {
-  Int _mp_size, _mp_alloc;
-  mp_limb_t *_mp_d;
-} MP_INT;
-
-typedef struct {
-  MP_INT _mp_num;
-  MP_INT _mp_den;
-} MP_RAT;
-
-#endif
-
 INLINE_ONLY bool IsBigIntTerm(Term);
 
 INLINE_ONLY bool IsBigIntTerm(Term t) {
@@ -415,7 +395,11 @@ INLINE_ONLY bool IsBigIntTerm(Term t) {
           FunctorOfTerm(t) == FunctorBigInt;
 }
 
-#ifdef USE_GMP
+
+#if !defined(__cplusplus)
+#include <gmp.h>
+#endif
+
 
 Term Yap_MkBigIntTerm(MP_INT *);
 MP_INT *Yap_BigIntOfTerm(Term);
diff --git a/H/YapEval.h b/H/YapEval.h
old mode 100644
new mode 100755
index 7b8cde243..48d24c0ed
--- a/H/YapEval.h
+++ b/H/YapEval.h
@@ -632,13 +632,13 @@ __Yap_Mk64IntegerTerm(YAP_LONG_LONG i USES_REGS) {
 }
 
 inline static Term add_int(Int i, Int j USES_REGS) {
-#if defined(__clang__) || defined(__GNUC__)
+#if defined(__clang__) || (defined(__GNUC__) && __GNUC__ > 4)
   Int w;
   if (!__builtin_add_overflow(i, j, &w))
     RINT(w);
   return Yap_gmp_add_ints(i, j);
   ;
-#elif defined(__GNUC__)
+#elif defined(__GNUC__) && __GNUC__ > 4
   Int w;
   if (!__builtin_add_overflow_p(i, j, w))
     RINT(w);
diff --git a/H/arith2.h b/H/arith2.h
index 723db794a..12d78f0c0 100755
--- a/H/arith2.h
+++ b/H/arith2.h
@@ -24,13 +24,13 @@ inline static int sub_overflow(Int x, Int i, Int j) {
 }
 
 inline static Term sub_int(Int i, Int j USES_REGS) {
-#if defined(__clang__ ) || defined(__GNUC__)
+#if defined(__clang__ ) || (defined(__GNUC__) && __GNUC__ > 4)
     Int k;
     if (__builtin_sub_overflow(i,j,&k)) {
       return Yap_gmp_sub_ints(i, j);
     }
     RINT(k);
-#elif defined(__GNUC__)
+#elif defined(__GNUC__) && __GNUC__ >4
     Int w;
     if (!__builtin_sub_overflow_p(i,j,w))
          RINT(w);
@@ -64,7 +64,7 @@ inline static int mul_overflow(Int z, Int i1, Int i2) {
   return (i2 && z / i2 != i1);
 }
 
-#if defined(__clang__) || defined(__GNUC__)
+#if defined(__clang__) || (defined(__GNUC__) && __GNUC__ > 4)
 #define DO_MULTI()                                                             \
   if (__builtin_mul_overflow(i1, i2, &z)) {                                   \
     goto overflow;                                                             \
diff --git a/os/fmem.c b/os/fmem.c
old mode 100644
new mode 100755
index faebfb81e..b50763a5d
--- a/os/fmem.c
+++ b/os/fmem.c
@@ -23,6 +23,9 @@ static char SccsId[] = "%W% %G%";
  *
  */
 
+#define _GNU_SOURCE
+
+
 #include "YapText.h"
 #include "format.h"
 #include "sysbits.h"
@@ -163,7 +166,7 @@ int Yap_open_buf_read_stream(const char *buf, size_t nchars,
   f = st->file = fmemopen((void *)buf, nchars, "r");
   st->vfs = NULL;
   flags = Input_Stream_f | InMemory_Stream_f | Seekable_Stream_f;
-  Yap_initStream(sno, f, RepAtom(fname)->StrOfAE, "r", uname, encoding, flags, NULL);
+  Yap_initStream(sno, f, fname, "r", uname, encoding, flags, NULL);
   // like any file stream.
   Yap_DefaultStreamOps(st);
   UNLOCK(st->streamlock);
diff --git a/os/iopreds.c b/os/iopreds.c
index 46473af86..f163624ff 100644
--- a/os/iopreds.c
+++ b/os/iopreds.c
@@ -342,7 +342,7 @@ void Yap_DefaultStreamOps(StreamDesc *st) {
     st->stream_putc = st->vfs->put_char;
     st->stream_wputc = st->vfs->put_wchar;
     st->stream_getc = st->vfs->get_char;
-    st->stream_wgetc = st->vfs->get_char;
+    st->stream_wgetc = st->vfs->get_wchar;
     default_peek(st);
     return;
   } else {
@@ -1126,7 +1126,7 @@ static void check_bom(int sno, StreamDesc *st) {
   }
 }
 
-bool Yap_initStream(int sno, FILE *fd, const char *name, const char *io_mode,
+bool Yap_initStream(int sno, FILE *fd, Atom name, const char *io_mode,
                     Term file_name, encoding_t encoding, stream_flags_t flags,
                     void *vfs) {
   // fprintf(stderr,"+ %s --> %d\n", name, sno);
@@ -1228,7 +1228,8 @@ typedef enum open_enum_choices { OPEN_DEFS() } open_choices_t;
 static const param_t open_defs[] = {OPEN_DEFS()};
 #undef PAR
 
-static bool fill_stream(int sno, StreamDesc *st, Term tin, const char *io_mode,  Term user_name, encoding_t enc) {
+static bool fill_stream(int sno, StreamDesc *st, Term tin, const char *io_mode,
+                        Term user_name, encoding_t enc) {
   struct vfs *vfsp = NULL;
   const char *fname;
 
@@ -1273,7 +1274,7 @@ static bool fill_stream(int sno, StreamDesc *st, Term tin, const char *io_mode,
       if (strchr(io_mode, 'r')) {
         return Yap_OpenBufWriteStream(PASS_REGS1);
       } else {
-	int j= push_text_stack();
+        int j = push_text_stack();
         const char *buf;
 
         buf = Yap_TextTermToText(tin PASS_REGS);
@@ -1283,11 +1284,10 @@ static bool fill_stream(int sno, StreamDesc *st, Term tin, const char *io_mode,
         }
         buf = pop_output_text_stack(j, buf);
         Atom nat = Yap_LookupAtom(Yap_StrPrefix(buf, 32));
-        sno = Yap_open_buf_read_stream(buf, strlen(buf) + 1,
-				       &LOCAL_encoding,
+        sno = Yap_open_buf_read_stream(buf, strlen(buf) + 1, &LOCAL_encoding,
                                        MEM_BUF_MALLOC, nat,
                                        MkAtomTerm(NameOfFunctor(f)));
-	pop_text_stack(j);
+        pop_text_stack(j);
         return Yap_OpenBufWriteStream(PASS_REGS1);
       }
     } else if (!strcmp(RepAtom(NameOfFunctor(f))->StrOfAE, "popen")) {
@@ -1313,8 +1313,8 @@ static bool fill_stream(int sno, StreamDesc *st, Term tin, const char *io_mode,
   if (!strchr(io_mode, 'b') && binary_file(fname)) {
     st->status |= Binary_Stream_f;
   }
-  Yap_initStream(sno, st->file, fname, io_mode, user_name, LOCAL_encoding,
-                 st->status, vfsp);
+  Yap_initStream(sno, st->file, Yap_LookupAtom(fname), io_mode, user_name,
+                 LOCAL_encoding, st->status, vfsp);
   return true;
 }
 
@@ -1670,7 +1670,7 @@ int Yap_OpenStream(Term tin, const char *io_mode, Term user_name,
   return -1;
 }
 
-int Yap_FileStream(FILE *fd, char *name, Term file_name, int flags,
+int Yap_FileStream(FILE *fd, Atom name, Term file_name, int flags,
                    VFS_t *vfsp) {
   CACHE_REGS
   int sno;
diff --git a/os/iopreds.h b/os/iopreds.h
old mode 100644
new mode 100755
index 3980a2efb..972937ee0
--- a/os/iopreds.h
+++ b/os/iopreds.h
@@ -31,7 +31,7 @@ INLINE_ONLY bool IsStreamTerm(Term t) {
           (IsApplTerm(t) && (FunctorOfTerm(t) == FunctorStream)));
 }
 
-extern bool Yap_initStream(int sno, FILE *fd, const char *name, const char *io_mode, Term file_name, encoding_t encoding,
+extern bool Yap_initStream(int sno, FILE *fd, Atom name, const char *io_mode, Term file_name, encoding_t encoding,
                            stream_flags_t flags, void *vfs);
 
 #define Yap_CheckStream(arg, kind, msg)                                        \
diff --git a/os/mem.c b/os/mem.c
old mode 100644
new mode 100755
index b8623ddc1..a0b321ec0
--- a/os/mem.c
+++ b/os/mem.c
@@ -225,7 +225,7 @@ int Yap_open_buf_read_stream(const char *buf, size_t nchars, encoding_t *encp,
   flags = Input_Stream_f | InMemory_Stream_f;
   st->vfs = NULL;
   st->name = name;
-  Yap_initStream(sno, f, "Memory Stream","wa", TermNil, encoding, flags, NULL);
+  Yap_initStream(sno, f, Yap_LookupAtom("Memory Stream"),"wa", TermNil, encoding, flags, NULL);
   // like any file stream.
   /* currently these streams are not seekable */
   st->status = Input_Stream_f | InMemory_Stream_f;
diff --git a/os/readline.c b/os/readline.c
old mode 100644
new mode 100755
index 01b240eb9..341d737e5
--- a/os/readline.c
+++ b/os/readline.c
@@ -218,7 +218,7 @@ static char **prolog_completion(const char *text, int start, int end) {
   } else if (start == 0) {
     int i = 0;
     const char *p;
-    while (isblank(text[i++]) && i <= end)
+    while (isspace(text[i++]) && i <= end)
       ;
     p = text + i;
 
diff --git a/os/streams.c b/os/streams.c
index a56838f64..dff198cbe 100644
--- a/os/streams.c
+++ b/os/streams.c
@@ -363,7 +363,6 @@ Atom Yap_guessFileName(FILE *file, int sno, size_t max) {
   }
 #endif
   if (!StreamName(sno)) {
-    pop_text_stack(i);
     return NULL;
   }
   pop_text_stack(i);
diff --git a/os/yapio.h b/os/yapio.h
index 58f4827aa..983522f19 100644
--- a/os/yapio.h
+++ b/os/yapio.h
@@ -26,8 +26,8 @@
 #include <wchar.h>
 
 #include "YapIOConfig.h"
-#include <Yatom.h>
 #include <VFS.h>
+#include <Yatom.h>
 
 #ifndef _PL_WRITE_
 
@@ -51,7 +51,7 @@ typedef struct AliasDescS {
  * @return a new VFS that will support /assets
  */
 
-extern struct vfs *Yap_InitAssetManager( void );
+extern struct vfs *Yap_InitAssetManager(void);
 
 /* routines in parser.c */
 extern VarEntry *Yap_LookupVar(const char *);
@@ -85,8 +85,9 @@ extern int Yap_PlGetWchar(void);
 extern int Yap_PlFGetchar(void);
 extern int Yap_GetCharForSIGINT(void);
 extern Int Yap_StreamToFileNo(Term);
-extern int Yap_OpenStream(Term tin, const char* io_mode, Term user_name, encoding_t enc);
-extern int Yap_FileStream(FILE*, char *, Term, int, VFS_t *);
+extern int Yap_OpenStream(Term tin, const char *io_mode, Term user_name,
+                          encoding_t enc);
+extern int Yap_FileStream(FILE *, Atom, Term, int, VFS_t *);
 extern char *Yap_TermToBuffer(Term t, int flags);
 extern char *Yap_HandleToString(yhandle_t l, size_t sz, size_t *length,
                                 encoding_t *encoding, int flags);
@@ -112,18 +113,19 @@ typedef enum mem_buf_source {
 
 extern char *Yap_MemStreamBuf(int sno);
 
-extern char *Yap_StrPrefix( const char *buf, size_t n) ;
+extern char *Yap_StrPrefix(const char *buf, size_t n);
 
 extern Term Yap_StringToNumberTerm(const char *s, encoding_t *encp,
                                    bool error_on);
 extern int Yap_FormatFloat(Float f, char **s, size_t sz);
 extern int Yap_open_buf_read_stream(const char *buf, size_t nchars,
-                                    encoding_t *encp, memBufSource src, Atom name,
-                                    Term uname);
+                                    encoding_t *encp, memBufSource src,
+                                    Atom name, Term uname);
 extern int Yap_open_buf_write_stream(encoding_t enc, memBufSource src);
-extern Term Yap_BufferToTerm(const  char *s, Term opts);
-extern X_API Term Yap_BufferToTermWithPrioBindings(const  char *s, Term opts, Term bindings, size_t sz,
-                                 int prio);
+extern Term Yap_BufferToTerm(const char *s, Term opts);
+extern X_API Term Yap_BufferToTermWithPrioBindings(const char *s, Term opts,
+                                                   Term bindings, size_t sz,
+                                                   int prio);
 extern FILE *Yap_GetInputStream(Term t, const char *m);
 extern FILE *Yap_GetOutputStream(Term t, const char *m);
 extern Atom Yap_guessFileName(FILE *f, int sno, size_t max);
@@ -156,36 +158,34 @@ INLINE_ONLY Term MkCharTerm(Int c) {
   return MkAtomTerm(Yap_ULookupAtom(cs));
 }
 
-
-
 extern char *GLOBAL_cwd;
 
+INLINE_ONLY char *Yap_VF(const char *path) {
+  char *out;
 
-INLINE_ONLY  char *Yap_VF(const char *path){
-    char *out;
-
-    out = (char *)malloc(YAP_FILENAME_MAX+1);
-    if ( GLOBAL_cwd == NULL || GLOBAL_cwd[0] == 0 || !Yap_IsAbsolutePath(path, false)) {
-        return (char *) path;
-    }
-    strcpy(out, GLOBAL_cwd);
-    strcat(out, "/" );
-    strcat(out, path);
-    return out;
+  out = (char *)malloc(YAP_FILENAME_MAX + 1);
+  if (GLOBAL_cwd == NULL || GLOBAL_cwd[0] == 0 ||
+      !Yap_IsAbsolutePath(path, false)) {
+    return (char *)path;
+  }
+  strcpy(out, GLOBAL_cwd);
+  strcat(out, "/");
+  strcat(out, path);
+  return out;
 }
 
+INLINE_ONLY char *Yap_VFAlloc(const char *path) {
+  char *out;
 
-INLINE_ONLY  char *Yap_VFAlloc(const char *path){
-    char *out;
-
-    out = (char *)malloc(YAP_FILENAME_MAX+1);
-    if ( GLOBAL_cwd == NULL || GLOBAL_cwd[0] == 0 || !Yap_IsAbsolutePath(path, false)) {
-        return (char *) path;
-    }
-    strcpy(out, GLOBAL_cwd);
-    strcat(out, "/" );
-    strcat(out, path);
-    return out;
+  out = (char *)malloc(YAP_FILENAME_MAX + 1);
+  if (GLOBAL_cwd == NULL || GLOBAL_cwd[0] == 0 ||
+      !Yap_IsAbsolutePath(path, false)) {
+    return (char *)path;
+  }
+  strcpy(out, GLOBAL_cwd);
+  strcat(out, "/");
+  strcat(out, path);
+  return out;
 }
 
 /// UT when yap started
@@ -193,6 +193,4 @@ extern uint64_t Yap_StartOfWTimes;
 
 extern bool Yap_HandleSIGINT(void);
 
-
-
 #endif
diff --git a/pl/protect.yap b/pl/protect.yap
index 242d951c5..d7e489c09 100755
--- a/pl/protect.yap
+++ b/pl/protect.yap
@@ -48,7 +48,7 @@ prolog:'$protect' :-
     '$new_system_predicate'(Name,Arity,M),
     sub_atom(Name,0,1,_, '$'),
     functor(P,Name,Arity),
-    %'$hide_predicate'(P,M),
+%    '$hide_predicate'(P,M),
     fail.
 prolog:'$protect' :-
     current_atom(Name),