Re: [RFA] ada-valprint.c (ada_val_print_array): Assert elttype not null.

[Joel Brobecker <brobecker at adacore dot com>]

> If we pass null to printstr, it will dereference it.

> 2011-03-04  Michael Snyder  <msnyder@vmware.com>
> 
> 	* ada-valprint.c (ada_val_print_array): Assert elttype not null.

As a matter of fact, we wouldn't dereference it, because we would
also pass a null len.  But looking deeper, we shouldn't have a NULL
elttype at all in this branch.  Attached is what I checked in.

-- 
Joel

commit 7321f71ee137f68df0297d1e5c020328cd38c79a
Author: Joel Brobecker <brobecker@adacore.com>
Date:   Mon Mar 7 12:17:58 2011 +0400

    simplify ada-valprint.c:ada_val_print_array
    
    Two things:
      - Move the declaration of a couple of variables inside the block
        where they are actually used;
      - Remove some code that checks against NULL/zero, because the
        condition should always be false. Add some gdb_asserts to
        make sure we never fail those assumptions.
    
    gdb/ChangeLog:
    
            * ada-valprint.c (ada_val_print_array): Move the declaration of
            "byte_order" and "elttype" inside the block where these variables
            are actually used.  Remove some special handling for the case
            where "elttype" and "eltlen" are null.  Replace by a comment
            and a couple of assertion checks.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 4887026..965917c 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,12 @@
+2011-03-07  Joel Brobecker  <brobecker@adacore.com>
+	    Michael Snyder  <msnyder@vmware.com>
+
+	* ada-valprint.c (ada_val_print_array): Move the declaration of
+	"byte_order" and "elttype" inside the block where these variables
+	are actually used.  Remove some special handling for the case
+	where "elttype" and "eltlen" are null.  Replace by a comment
+	and a couple of assertion checks.
+
 2011-03-05  Michael Snyder  <msnyder@vmware.com>
 
 	* source.c (add_path): Replace semicolon at end of block.
diff --git a/gdb/ada-valprint.c b/gdb/ada-valprint.c
index 9381ecc..09266ce 100644
--- a/gdb/ada-valprint.c
+++ b/gdb/ada-valprint.c
@@ -605,25 +605,25 @@ ada_val_print_array (struct type *type, const gdb_byte *valaddr,
 		     const struct value *val,
 		     const struct value_print_options *options)
 {
-  enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
-  struct type *elttype = TYPE_TARGET_TYPE (type);
   int result = 0;
 
   /* For an array of chars, print with string syntax.  */
   if (ada_is_string_type (type)
       && (options->format == 0 || options->format == 's'))
     {
+      enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
+      struct type *elttype = TYPE_TARGET_TYPE (type);
       unsigned int eltlen;
       unsigned int len;
 
-      if (elttype == NULL)
-        eltlen = 0;
-      else
-        eltlen = TYPE_LENGTH (elttype);
-      if (eltlen == 0)
-        len = 0;
-      else
-        len = TYPE_LENGTH (type) / eltlen;
+      /* We know that ELTTYPE cannot possibly be null, because we found
+	 that TYPE is a string-like type.  Similarly, the size of ELTTYPE
+	 should also be non-null, since it's a character-like type.  */
+      gdb_assert (elttype != NULL);
+      gdb_assert (TYPE_LENGTH (elttype) != 0);
+
+      eltlen = TYPE_LENGTH (elttype);
+      len = TYPE_LENGTH (type) / eltlen;
 
       if (options->prettyprint_arrays)
         print_spaces_filtered (2 + 2 * recurse, stream);