RE: [PATCH 06/10] vla: update type from newly created value

["Agovic, Sanimir" <sanimir dot agovic at intel dot com>]

> -----Original Message-----
> From: Tom Tromey [mailto:tromey@redhat.com]
> Sent: Thursday, November 07, 2013 09:43 PM
> To: Agovic, Sanimir
> Cc: gdb-patches@sourceware.org
> Subject: Re: [PATCH 06/10] vla: update type from newly created value
> 
> >>>>> "Sanimir" == Sanimir Agovic <sanimir.agovic@intel.com> writes:
> 
> Sanimir> Constructing a value based on a type and address might change
> Sanimir> the type of the newly constructed value. Thus re-fetch type via
> Sanimir> value_type to ensure we have the correct type at hand.
> 
> Sanimir> 2013-10-18  Sanimir Agovic  <sanimir.agovic@intel.com>
> Sanimir>             Keven Boell  <keven.boell@intel.com>
> 
> Sanimir> 	* valops.c (value_ind): Re-fetch type from value.
> Sanimir> 	* value.c (coerce_ref): Re-fetch type from value.
> 
> This is fine by itself; however, I wonder whether there are other calls
> that require fixing.  Did you check through the rest of the code?
> 
My approach to find similar occurrences:
1) Grep sources for value_at / value_at_lazy / value_from_contents_and_address
2) Follow control flow within a function, if the type passed to the above
   constructors is used after constructing a value I re-fetched the type.

Running the testsuite before/after this patch series showed no regressions.
I used Jans diffgdb. gjc, gcc/++, pascal, and ada was used on Fedora20. 

I run into some ada fails with and without c99 patches. Not sure if this
is known or expected:
FAIL: gdb.ada/interface.exp: print s
FAIL: gdb.ada/iwide.exp: print My_Drawable
FAIL: gdb.ada/iwide.exp: print s_access.all
FAIL: gdb.ada/iwide.exp: print sp_access.all
FAIL: gdb.ada/iwide.exp: print d_access.all
FAIL: gdb.ada/iwide.exp: print dp_access.all
FAIL: gdb.ada/ptype_tagged_param.exp: ptype s
FAIL: gdb.ada/tagged.exp: ptype obj
FAIL: gdb.ada/tagged.exp: print obj

Below you will find all hits. Let me know if it is OK.

diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c
index 9ff3ab9..26d0c24 100644
--- a/gdb/ada-lang.c
+++ b/gdb/ada-lang.c
@@ -2299,6 +2299,7 @@ ada_value_primitive_packed_val (struct value *obj, const gdb_byte *valaddr,
   else if (VALUE_LVAL (obj) == lval_memory && value_lazy (obj))
     {
       v = value_at (type, value_address (obj));
+      type = value_type (v);
       bytes = (unsigned char *) alloca (len);
       read_memory (value_address (v) + offset, bytes, len);
     }
@@ -7656,6 +7657,7 @@ ada_template_to_fixed_record_type_1 (struct type *type,
                 size first before creating the value.  */
              check_size (rtype);
              dval = value_from_contents_and_address (rtype, valaddr, address);
+             rtype = value_type (dval);
            }
           else
             dval = dval0;
@@ -7758,7 +7760,10 @@ ada_template_to_fixed_record_type_1 (struct type *type,
       off = TYPE_FIELD_BITPOS (rtype, variant_field);

       if (dval0 == NULL)
-        dval = value_from_contents_and_address (rtype, valaddr, address);
+       {
+         dval = value_from_contents_and_address (rtype, valaddr, address);
+         rtype = value_type (dval);
+       }
       else
         dval = dval0;

@@ -7899,7 +7904,10 @@ to_record_with_fixed_variant_part (struct type *type, const gdb_byte *valaddr,
     return type;

   if (dval0 == NULL)
-    dval = value_from_contents_and_address (type, valaddr, address);
+    {
+      dval = value_from_contents_and_address (type, valaddr, address);
+      type = value_type (dval);
+    }
   else
     dval = dval0;

@@ -8197,6 +8205,8 @@ ada_to_fixed_type_1 (struct type *type, const gdb_byte *valaddr,
              value_from_contents_and_address (fixed_record_type,
                                               valaddr,
                                               address);
+
+            fixed_record_type = value_type (obj);
             if (real_type != NULL)
               return to_fixed_record_type
                (real_type, NULL,
diff --git a/gdb/cp-valprint.c b/gdb/cp-valprint.c
index 1d7147c..72c8d41 100644
--- a/gdb/cp-valprint.c
+++ b/gdb/cp-valprint.c
@@ -446,6 +446,7 @@ cp_print_value_fields_rtti (struct type *type,
       /* Ugh, we have to convert back to a value here.  */
       value = value_from_contents_and_address (type, valaddr + offset,
                                               address + offset);
+      type = value_type (value);
       /* We don't actually care about most of the result here -- just
         the type.  We already have the correct offset, due to how
         val_print was initially called.  */
@@ -548,6 +549,7 @@ cp_print_value (struct type *type, struct type *real_type,
                  base_val = value_from_contents_and_address (baseclass,
                                                              buf,
                                                              address + boffset);
+                 baseclass = value_type (base_val);
                  thisoffset = 0;
                  boffset = 0;
                  thistype = baseclass;
diff --git a/gdb/d-valprint.c b/gdb/d-valprint.c
index 6e9c28d..cca629a 100644
--- a/gdb/d-valprint.c
+++ b/gdb/d-valprint.c
@@ -59,6 +59,7 @@ dynamic_array_type (struct type *type, const gdb_byte *valaddr,

       true_type = lookup_array_range_type (true_type, 0, length - 1);
       ival = value_at (true_type, addr);
+      true_type = value_type (ival);

       d_val_print (true_type,
                   value_contents_for_printing (ival),
diff --git a/gdb/jv-valprint.c b/gdb/jv-valprint.c
index cb89a85..27901a3 100644
--- a/gdb/jv-valprint.c
+++ b/gdb/jv-valprint.c
@@ -65,6 +65,7 @@ java_value_print (struct value *val, struct ui_file *stream,
          type = lookup_pointer_type (type);

          val = value_at (type, address);
+         type = value_type (val);
        }
     }

diff --git a/gdb/valops.c b/gdb/valops.c
index 6706d9f..b539610 100644
--- a/gdb/valops.c
+++ b/gdb/valops.c
@@ -268,6 +268,7 @@ value_cast_structs (struct type *type, struct value *v2)
        {
          v = value_full_object (v2, real_type, full, top, using_enc);
          v = value_at_lazy (real_type, value_address (v));
+         real_type = value_type (v);

          /* We might be trying to cast to the outermost enclosing
             type, in which case search_struct_field won't work.  */
@@ -803,6 +804,7 @@ value_dynamic_cast (struct type *type, struct value *arg)
     return value_at_lazy (type, addr);

   tem = value_at (type, addr);
+  type = value_type (tem);

   /* The first dynamic check specified in 5.2.7.  */
   if (is_public_ancestor (arg_type, TYPE_TARGET_TYPE (resolved_type)))

 -Sanimir

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