[PATCH] Fix PR remote/9053: remove dead code on query packet size

[PATCH] Fix PR remote/9053: remove dead code on query packet size

[Yao Qi]

The code becomes dead as GDB evolves.  In 2003, Andrew Cagney post patch
https://sourceware.org/ml/gdb-patches/2003-10/msg00511.html to add target
read/write partial methods.  They support query buffer size when both
OFFSET and LEN is zero, and it was used in avr-tdep.c and kod.c.  Then,
Daniel added target_read_object_alloc and avr-tdep.c switches to use that
in patch https://sourceware.org/ml/gdb-patches/2006-07/msg00009.html
From then on, GDB on longer queries the buffer size, so the code
returning packet size in remote_xfer_partial became dead.

PR 17060 is duplicated of PR 9053, so I mention the latter in the
ChangeLog entry.  Rebuild GDB with this patch.  OK to apply?
I'll mark PR 17060 as duplicated once the patch is applied.

gdb:

2014-08-08  Yao Qi  <yao@codesourcery.com>

	PR remote/9053
	* remote.c (remote_xfer_partial): Remove dead code.
---
 gdb/remote.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/gdb/remote.c b/gdb/remote.c
index 473bb72..357e9f2 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -8863,10 +8863,6 @@ remote_xfer_partial (struct target_ops *ops, enum target_object object,
       return TARGET_XFER_E_IO;
     }
 
-  /* Note: a zero OFFSET and LEN can be used to query the minimum
-     buffer size.  */
-  if (offset == 0 && len == 0)
-    return (get_remote_packet_size ());
   /* Minimum outbuf size is get_remote_packet_size ().  If LEN is not
      large enough let the caller deal with it.  */
   if (len < get_remote_packet_size ())
-- 
1.9.0

Re: [PATCH] Fix PR remote/9053: remove dead code on query packet size

[Tom Tromey]

>>>>> "Yao" == Yao Qi <yao@codesourcery.com> writes:

Yao> 2014-08-08  Yao Qi  <yao@codesourcery.com>

Yao> 	PR remote/9053
Yao> 	* remote.c (remote_xfer_partial): Remove dead code.

Ok.

Tom

Re: [PATCH] Fix PR remote/9053: remove dead code on query packet size

[Yao Qi]

On 08/08/2014 09:57 PM, Tom Tromey wrote:
>>>>>> "Yao" == Yao Qi <yao@codesourcery.com> writes:
> 
> Yao> 2014-08-08  Yao Qi  <yao@codesourcery.com>
> 
> Yao> 	PR remote/9053
> Yao> 	* remote.c (remote_xfer_partial): Remove dead code.
> 
> Ok.

Patch is pushed in.

-- 
Yao (齐尧)