[ARM, sim] Fix build failure with -Werror (PR26365)

There is a bit of a situation in the ARM sim with regards to the handling
of argv. sim_open () gets a const char **argv, but ARM's sim_open gets
clever and decides to modify argv in place via sim_target_parse_command_line.
I'm not sure why.

In any case, here's a fix that makes the code modify a copy of argv instead.

sim/arm/ChangeLog:

2020-08-13  Luis Machado  <luis.machado@linaro.org>

	PR sim/26365

	* wrapper.c (sim_target_parse_command_line): Free discarded argv
	entries.
	(sim_open): Use a duplicate of argv instead of the original argv.

sim/arm/ChangeLog

@@ -1,3 +1,11 @@
+2020-08-13  Luis Machado  <luis.machado@linaro.org>
+
+	PR sim/26365
+
+	* wrapper.c (sim_target_parse_command_line): Free discarded argv
+	entries.
+	(sim_open): Use a duplicate of argv instead of the original argv.
+
 2020-01-17  Christian Biesinger  <cbiesinger@google.com>
 
 	* iwmmxt.c: Fix spelling error (seperate).

sim/arm/wrapper.c

@@ -672,7 +672,10 @@ sim_target_parse_command_line (int argc, char ** argv)
 	{
 	  /* Remove this option from the argv array.  */
 	  for (arg = i; arg < argc; arg ++)
-	    argv[arg] = argv[arg + 1];
+	    {
+	      free (argv[arg]);
+	      argv[arg] = argv[arg + 1];
+	    }
 	  argc --;
 	  i --;
 	  trace_funcs = 1;
@@ -683,7 +686,10 @@ sim_target_parse_command_line (int argc, char ** argv)
 	{
 	  /* Remove this option from the argv array.  */
 	  for (arg = i; arg < argc; arg ++)
-	    argv[arg] = argv[arg + 1];
+	    {
+	      free (argv[arg]);
+	      argv[arg] = argv[arg + 1];
+	    }
 	  argc --;
 	  i --;
 	  disas = 1;
@@ -697,7 +703,10 @@ sim_target_parse_command_line (int argc, char ** argv)
 	{
 	  /* Remove this option from the argv array.  */
 	  for (arg = i; arg < argc; arg ++)
-	    argv[arg] = argv[arg + 1];
+	    {
+	      free (argv[arg]);
+	      argv[arg] = argv[arg + 1];
+	    }
 	  argc --;
 
 	  ptr = argv[i];
@@ -733,7 +742,10 @@ sim_target_parse_command_line (int argc, char ** argv)
 
       /* Remove this option from the argv array.  */
       for (arg = i; arg < argc; arg ++)
-	argv[arg] = argv[arg + 1];
+	{
+	  free (argv[arg]);
+	  argv[arg] = argv[arg + 1];
+	}
       argc --;
       i --;
     }
@@ -774,6 +786,7 @@ sim_open (SIM_OPEN_KIND kind,
 	  char * const *argv)
 {
   int i;
+  char **argv_copy;
   SIM_DESC sd = sim_state_alloc (kind, cb);
   SIM_ASSERT (STATE_MAGIC (sd) == SIM_MAGIC_NUMBER);
 
@@ -836,21 +849,24 @@ sim_open (SIM_OPEN_KIND kind,
 
   sim_callback = cb;
 
-  sim_target_parse_arg_array (argv);
+  /* Copy over the argv contents so we can modify them.  */
+  argv_copy = dupargv (argv);
 
-  if (argv[1] != NULL)
+  sim_target_parse_arg_array (argv_copy);
+
+  if (argv_copy[1] != NULL)
     {
       int i;
 
       /* Scan for memory-size switches.  */
-      for (i = 0; (argv[i] != NULL) && (argv[i][0] != 0); i++)
-	if (argv[i][0] == '-' && argv[i][1] == 'm')
+      for (i = 0; (argv_copy[i] != NULL) && (argv_copy[i][0] != 0); i++)
+	if (argv_copy[i][0] == '-' && argv_copy[i][1] == 'm')
 	  {
-	    if (argv[i][2] != '\0')
-	      mem_size = atoi (&argv[i][2]);
-	    else if (argv[i + 1] != NULL)
+	    if (argv_copy[i][2] != '\0')
+	      mem_size = atoi (&argv_copy[i][2]);
+	    else if (argv_copy[i + 1] != NULL)
 	      {
-		mem_size = atoi (argv[i + 1]);
+		mem_size = atoi (argv_copy[i + 1]);
 		i++;
 	      }
 	    else
@@ -862,6 +878,8 @@ sim_open (SIM_OPEN_KIND kind,
 	  }
     }
 
+  freeargv (argv_copy);
+
   return sd;
 }