fix string_concat/2

C/atomic.c

@@ -808,6 +808,53 @@ p_atom_concat2( USES_REGS1 )
   cut_fail();
 }
 
+static Int 
+p_string_concat2( USES_REGS1 )
+{
+  Term t1;
+  Term *tailp;
+  Int n;
+ restart_aux:
+  t1 = Deref(ARG1);
+  n = Yap_SkipList(&t1, &tailp);
+  if (*tailp != TermNil) {
+    LOCAL_Error_TYPE = TYPE_ERROR_LIST;
+  } else {
+    seq_tv_t *inpv = (seq_tv_t *)malloc(n*sizeof(seq_tv_t)), out;
+    int i = 0;
+    
+    if (!inpv) {
+      LOCAL_Error_TYPE = OUT_OF_HEAP_ERROR;
+      free(inpv);
+      goto error;
+    }
+
+    while (t1 != TermNil) {
+      inpv[i].type = YAP_STRING_STRING;
+      inpv[i].val.t = HeadOfTerm(t1);
+      i++;
+      t1 = TailOfTerm(t1);
+    }
+    out.type = YAP_STRING_STRING;
+    if (!Yap_Concat_Text(n, inpv, &out PASS_REGS)) {
+      free(inpv);
+      goto error;
+    }
+    free(inpv);
+    if (out.val.t) return Yap_unify(ARG2, out.val.t);
+  }
+ error:
+  /* Error handling */
+  if (LOCAL_Error_TYPE) {
+    if (Yap_HandleError( "string_code/3" )) {
+      goto restart_aux;
+    } else {
+      return FALSE;
+    }
+  }
+  cut_fail();
+}
+
 
 static Int 
 p_atomic_concat2( USES_REGS1 )
@@ -1929,6 +1976,7 @@ Yap_InitAtomPreds(void)
   Yap_InitCPred("atom_number", 2, p_atom_number, 0);
   Yap_InitCPred("string_number", 2, p_string_number, 0);
   Yap_InitCPred("$atom_concat", 2, p_atom_concat2, 0);
+  Yap_InitCPred("$string_concat", 2, p_string_concat2, 0);
   Yap_InitCPred("atomic_concat", 2, p_atomic_concat2, 0);
   Yap_InitCPred("atomic_concat", 3, p_atomic_concat3, 0);
   Yap_InitCPred("atomics_to_string", 2, p_atomics_to_string2, 0);

C/index.c

@@ -4589,7 +4589,8 @@ remove_dirty_clauses_from_index(yamop *header)
   curp->opc = startopc;
   if (curp->opc == endop)
     return;
-  if (!header->u.Illss.e)
+  // don't try to follow the chain if there is no chain.
+  if (header->u.Illss.e <= 1)
     return;
   previouscurp = curp;
   curp = curp->u.OtaLl.n;

C/sysbits.c

@@ -2086,21 +2086,28 @@ Run an external command and wait for its completion.
   char *shell;
   register int bourne = FALSE;
   Term t1 = Deref (ARG1);
+  const char *cmd;
 
   shell = (char *) getenv ("SHELL");
   if (!strcmp (shell, "/bin/sh"))
     bourne = TRUE;
   if (shell == NIL)
     bourne = TRUE;
+  if (IsAtomTerm(t1))
+    cmd = RepAtom(AtomOfTerm(t1))->StrOfAE;
+  else if (IsStringTerm(t1))
+    cmd = StringOfTerm(t1);
+  else
+    return FALSE;
   /* Yap_CloseStreams(TRUE); */
   if (bourne)
-    return system(RepAtom(AtomOfTerm(t1))->StrOfAE) == 0;
+    return system( cmd ) == 0;
   else {
     int status = -1;
     int child = fork ();
 
     if (child == 0) {			/* let the children go */
-      if (!execl (shell, shell, "-c", RepAtom(AtomOfTerm(t1))->StrOfAE , NULL)) {
+      if (!execl (shell, shell, "-c", cmd , NULL)) {
 	exit(-1);
       }
       exit(TRUE);
@@ -2182,13 +2189,15 @@ Run an external command and wait for its completion.
   return FALSE;
 #elif HAVE_SYSTEM
   Term t1 = Deref (ARG1);
-  char *s;
+  const char *s;
 
   if (IsVarTerm(t1)) {
     Yap_Error(INSTANTIATION_ERROR,t1,"argument to system/1 unbound");
     return FALSE;
   } else if (IsAtomTerm(t1)) {
     s = RepAtom(AtomOfTerm(t1))->StrOfAE;
+  } else if (IsStringTerm(t1)) {
+    s = StringOfTerm(t1);
   } else {
     if (!Yap_GetName (LOCAL_FileNameBuf, YAP_FILENAME_MAX, t1)) {
       Yap_Error(TYPE_ERROR_ATOM,t1,"argument to system/1");