RE: [PATCH v3 05/13] vla: update type from newly created value

Agovic, Sanimir
2013-12-16T15:21:00Z

> -----Original Message-----
> From: Doug Evans [mailto:xdje42@gmail.com]
> Sent: Friday, December 06, 2013 08:36 AM
> To: Agovic, Sanimir
> Cc: tromey@redhat.com; palves@redhat.com; xdje42@gmail.com; gdb-patches@sourceware.org;
> Boell, Keven
> Subject: Re: [PATCH v3 05/13] vla: update type from newly created value
>
> > * ada-lang.c (ada_value_primitive_packed_val): Re-fetch type from value.
>
> Hi. Can you add a comment to each of the functions that
> require this, saying something like "You must do <this> after calling me."
> value_at, value_from_contents_and_address, others?
>
Thanks Doug, below is the diff being part of v4. Please let me know it is OK.

diff --git a/gdb/valops.c b/gdb/valops.c
index ec2f1f6..1bccacc 100644
--- a/gdb/valops.c
+++ b/gdb/valops.c
@@ -904,7 +904,9 @@ value_one (struct type *type)
return val;
}

-/* Helper function for value_at, value_at_lazy, and value_at_lazy_stack. */
+/* Helper function for value_at, value_at_lazy, and value_at_lazy_stack.
+ The type of the created value may differ from the passed type TYPE.
+ Make sure to retrieve values new type after this call. */

static struct value *
get_value_at (struct type *type, CORE_ADDR addr, int lazy)
@@ -929,7 +931,9 @@ get_value_at (struct type *type, CORE_ADDR addr, int lazy)
value_at_lazy instead. value_at_lazy simply records the address of
the data and sets the lazy-evaluation-required flag. The lazy flag
is tested in the value_contents macro, which is used if and when
- the contents are actually required.
+ the contents are actually required. The type of the created value
+ may differ from the passed type TYPE. Make sure to retrieve values
+ new type after this call.

Note: value_at does *NOT* handle embedded offsets; perform such
adjustments before or after calling it. */
diff --git a/gdb/value.c b/gdb/value.c
index f1cf4dd..3f445f8 100644
--- a/gdb/value.c
+++ b/gdb/value.c
@@ -3193,7 +3193,8 @@ value_from_pointer (struct type *type, CORE_ADDR addr)

/* Create a value of type TYPE whose contents come from VALADDR, if it
is non-null, and whose memory address (in the inferior) is
- ADDRESS. */
+ ADDRESS. The type of the created value may differ from the passed
+ type TYPE. Make sure to retrieve values new type after this call. */

struct value *
value_from_contents_and_address (struct type *type,
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