More invalid pointer to pointer conversions.

As a follow up to:

  http://sourceware.org/ml/gdb-patches/2013-03/msg00449.html

In a nutshell, casts between 'char **' <-> 'unsigned char **' and
'char **' <-> 'const char **' are invalid.

I grepped for "\*\*) &" and found these.  There's another one in
demangle.c, but I've split fixing that one to a separate patch.

I think the ada_decode_symbol change is perhaps the one that could be
surprising.  The function's description has this comment, which makes
things much clearer:

   The GSYMBOL parameter is "mutable" in the C++ sense: logically
   const, but nevertheless modified to a semantically equivalent form
   when a decoded name is cached in it.  */

 const char *
 ada_decode_symbol (const struct general_symbol_info *gsymbol)

With that out of the way, I think the patch ends up being pretty
obvious.

Tested on x86_64 Fedora 17.

gdb/
2013-03-13  Pedro Alves  <palves@redhat.com>

	* ada-lang.c (ada_decode_symbol): Cast away constness of GSYMBOL
	rather than casting 'const char * const *' to 'const char **'.
	* ada-lex.l (processInt): Make "trailer" local const.  Remove
	'const char **' cast.
	* arm-linux-tdep.c (arm_stap_parse_special_token): Add 'char *'
	locals, and use those as strtol output pointer, instead than doing
	invalid casts to from 'const char **' to 'char **'.
	(_initialize_demangle): Remove cast.
	* i386-tdep.c (i386_stap_parse_special_token): : Add 'char *'
	locals, and use those as strtol output pointer, instead than doing
	invalid casts to from 'const char **' to 'char **'.
	* solib-dsbt.c (dsbt_get_initial_loadmaps): Remove 'gdb_byte**'
	casts.
	* stap-probe.c (stap_parse_register_operand)
	(stap_parse_single_operand): Likewise.

gdb/ChangeLog

@@ -1,3 +1,21 @@
+2013-03-13  Pedro Alves  <palves@redhat.com>
+
+	* ada-lang.c (ada_decode_symbol): Cast away constness of GSYMBOL
+	rather than casting 'const char * const *' to 'const char **'.
+	* ada-lex.l (processInt): Make "trailer" local const.  Remove
+	'const char **' cast.
+	* arm-linux-tdep.c (arm_stap_parse_special_token): Add 'char *'
+	locals, and use those as strtol output pointer, instead than doing
+	invalid casts to from 'const char **' to 'char **'.
+	(_initialize_demangle): Remove cast.
+	* i386-tdep.c (i386_stap_parse_special_token): : Add 'char *'
+	locals, and use those as strtol output pointer, instead than doing
+	invalid casts to from 'const char **' to 'char **'.
+	* solib-dsbt.c (dsbt_get_initial_loadmaps): Remove 'gdb_byte**'
+	casts.
+	* stap-probe.c (stap_parse_register_operand)
+	(stap_parse_single_operand): Likewise.
+
 2013-03-13  Yao Qi  <yao@codesourcery.com>
 
 	* tracepoint.c (tfile_get_trace_state_variable_value): Look for

gdb/ada-lang.c

@@ -1299,8 +1299,10 @@ static struct htab *decoded_names_store;
 const char *
 ada_decode_symbol (const struct general_symbol_info *gsymbol)
 {
-  const char **resultp =
+  struct general_symbol_info *gsymbol_rw
-    (const char **) &gsymbol->language_specific.mangled_lang.demangled_name;
+    = (struct general_symbol_info *) gsymbol;
+  const char **resultp
+    = &gsymbol_rw->language_specific.mangled_lang.demangled_name;
 
   if (*resultp == NULL)
     {

gdb/ada-lex.l

@@ -329,8 +329,7 @@ processInt (const char *base0, const char *num0, const char *exp0)
   ULONGEST result;
   long exp;
   int base;
-
+  const char *trailer;
-  char *trailer;
 
   if (base0 == NULL)
     base = 10;
@@ -347,7 +346,7 @@ processInt (const char *base0, const char *num0, const char *exp0)
     exp = strtol(exp0, (char **) NULL, 10);
 
   errno = 0;
-  result = strtoulst (num0, (const char **) &trailer, base);
+  result = strtoulst (num0, &trailer, base);
   if (errno == ERANGE)
     error (_("Integer literal out of range"));
   if (isxdigit(*trailer))

gdb/arm-linux-tdep.c

@@ -1088,6 +1088,7 @@ arm_stap_parse_special_token (struct gdbarch *gdbarch,
     {
       /* Temporary holder for lookahead.  */
       const char *tmp = p->arg;
+      char *endp;
       /* Used to save the register name.  */
       const char *start;
       char *regname;
@@ -1140,7 +1141,8 @@ arm_stap_parse_special_token (struct gdbarch *gdbarch,
 	  got_minus = 1;
 	}
 
-      displacement = strtol (tmp, (char **) &tmp, 10);
+      displacement = strtol (tmp, &endp, 10);
+      tmp = endp;
 
       /* Skipping last `]'.  */
       if (*tmp++ != ']')

gdb/i386-tdep.c

@@ -3494,6 +3494,7 @@ i386_stap_parse_special_token (struct gdbarch *gdbarch,
 		  char *regname;
 		  int len;
 		  struct stoken str;
+		  char *endp;
 
 		  got_minus[0] = 0;
 		  if (*s == '+')
@@ -3504,7 +3505,8 @@ i386_stap_parse_special_token (struct gdbarch *gdbarch,
 		      got_minus[0] = 1;
 		    }
 
-		  displacements[0] = strtol (s, (char **) &s, 10);
+		  displacements[0] = strtol (s, &endp, 10);
+		  s = endp;
 
 		  if (*s != '+' && *s != '-')
 		    {
@@ -3521,7 +3523,8 @@ i386_stap_parse_special_token (struct gdbarch *gdbarch,
 		      got_minus[1] = 1;
 		    }
 
-		  displacements[1] = strtol (s, (char **) &s, 10);
+		  displacements[1] = strtol (s, &endp, 10);
+		  s = endp;
 
 		  if (*s != '+' && *s != '-')
 		    {
@@ -3538,7 +3541,8 @@ i386_stap_parse_special_token (struct gdbarch *gdbarch,
 		      got_minus[2] = 1;
 		    }
 
-		  displacements[2] = strtol (s, (char **) &s, 10);
+		  displacements[2] = strtol (s, &endp, 10);
+		  s = endp;
 
 		  if (*s != '(' || s[1] != '%')
 		    break;
@@ -3628,7 +3632,12 @@ i386_stap_parse_special_token (struct gdbarch *gdbarch,
 		    break;
 
 		  if (isdigit (*s))
-		    offset = strtol (s, (char **) &s, 10);
+		    {
+		      char *endp;
+
+		      offset = strtol (s, &endp, 10);
+		      s = endp;
+		    }
 
 		  if (*s != '(' || s[1] != '%')
 		    break;
@@ -3675,6 +3684,8 @@ i386_stap_parse_special_token (struct gdbarch *gdbarch,
 
 		  if (*s == ',')
 		    {
+		      char *endp;
+
 		      ++s;
 		      if (*s == '+')
 			++s;
@@ -3684,7 +3695,8 @@ i386_stap_parse_special_token (struct gdbarch *gdbarch,
 			  size_minus = 1;
 			}
 
-		      size = strtol (s, (char **) &s, 10);
+		      size = strtol (s, &endp, 10);
+		      s = endp;
 
 		      if (*s != ')')
 			break;

gdb/solib-dsbt.c

@@ -298,7 +298,7 @@ dsbt_get_initial_loadmaps (void)
   struct dsbt_info *info = get_dsbt_info ();
 
   if (0 >= target_read_alloc (&current_target, TARGET_OBJECT_FDPIC,
-			      "exec", (gdb_byte**) &buf))
+			      "exec", &buf))
     {
       info->exec_loadmap = NULL;
       error (_("Error reading DSBT exec loadmap"));
@@ -308,7 +308,7 @@ dsbt_get_initial_loadmaps (void)
     dsbt_print_loadmap (info->exec_loadmap);
 
   if (0 >= target_read_alloc (&current_target, TARGET_OBJECT_FDPIC,
-			      "interp", (gdb_byte**)&buf))
+			      "interp", &buf))
     {
       info->interp_loadmap = NULL;
       error (_("Error reading DSBT interp loadmap"));

gdb/stap-probe.c

@@ -422,9 +422,11 @@ stap_parse_register_operand (struct stap_parse_info *p)
     {
       /* The value of the displacement.  */
       long displacement;
+      char *endp;
 
       disp_p = 1;
-      displacement = strtol (p->arg, (char **) &p->arg, 10);
+      displacement = strtol (p->arg, &endp, 10);
+      p->arg = endp;
 
       /* Generating the expression for the displacement.  */
       write_exp_elt_opcode (OP_LONG);
@@ -598,7 +600,12 @@ stap_parse_single_operand (struct stap_parse_info *p)
 	tmp = skip_spaces_const (tmp);
 
       if (isdigit (*tmp))
-	number = strtol (tmp, (char **) &tmp, 10);
+	{
+	  char *endp;
+
+	  number = strtol (tmp, &endp, 10);
+	  tmp = endp;
+	}
 
       if (!reg_ind_prefix
 	  || strncmp (tmp, reg_ind_prefix, reg_ind_prefix_len) != 0)
@@ -627,11 +634,13 @@ stap_parse_single_operand (struct stap_parse_info *p)
     {
       /* A temporary variable, needed for lookahead.  */
       const char *tmp = p->arg;
+      char *endp;
       long number;
 
       /* We can be dealing with a numeric constant (if `const_prefix' is
 	 NULL), or with a register displacement.  */
-      number = strtol (tmp, (char **) &tmp, 10);
+      number = strtol (tmp, &endp, 10);
+      tmp = endp;
 
       if (p->inside_paren_p)
 	tmp = skip_spaces_const (tmp);
@@ -667,9 +676,11 @@ stap_parse_single_operand (struct stap_parse_info *p)
     {
       /* We are dealing with a numeric constant.  */
       long number;
+      char *endp;
 
       p->arg += const_prefix_len;
-      number = strtol (p->arg, (char **) &p->arg, 10);
+      number = strtol (p->arg, &endp, 10);
+      p->arg = endp;
 
       write_exp_elt_opcode (OP_LONG);
       write_exp_elt_type (builtin_type (gdbarch)->builtin_long);