Re: [PATCH 3/3] Fix "Remote 'g' packet reply is too long" problems with multiple inferiors

[Pedro Alves <palves@redhat.com>]

On 10/03/2017 12:40 PM, Yao Qi wrote:
> Pedro Alves <palves@redhat.com> writes:
> 
>>  struct gdbarch *
>>  default_thread_architecture (struct target_ops *ops, ptid_t ptid)
>>  {
>> -  return target_gdbarch ();
>> +  inferior *inf = find_inferior_ptid (ptid);
>> +  gdb_assert (inf != NULL);
>> +  return inf->gdbarch;
>>  }
> 
> It is right, but forgot to mention that we need to update
> spu_thread_architecture too,
> 
>   if (parse_spufs_run (ptid, &spufs_fd, &spufs_addr))
>     return spu_gdbarch (spufs_fd);
> 
>   return target_gdbarch ();
> 
> it looks wrong to call target_gdbarch.  We may need to replace
> target_gdbarch with default_thread_architecture.

I think you're right.  

The target_gdbarch reference in process_stop_reply looks incorrect
as well (last hunk below).  I'm current running test with the patch below
on top.  Kind of curious that I didn't run into this one before.

From 60956bf76cf0b5582f4085f8f36f1ee0bf7f804f Mon Sep 17 00:00:00 2001
From: Pedro Alves <palves@redhat.com>
Date: Mon, 2 Oct 2017 18:23:10 +0100
Subject: [PATCH] more target_gdbarch

---
 gdb/remote.c | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/gdb/remote.c b/gdb/remote.c
index b6a81a2..894c3de 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -6363,6 +6363,9 @@ typedef struct stop_reply
 
   struct target_waitstatus ws;
 
+  /* The architecture associated with the expedited registers.  */
+  gdbarch *arch;
+
   /* Expedited registers.  This makes remote debugging a bit more
      efficient for those targets that provide critical registers as
      part of their normal status mechanism (as another roundtrip to
@@ -6838,7 +6841,6 @@ static void
 remote_parse_stop_reply (char *buf, struct stop_reply *event)
 {
   remote_arch_state *rsa = NULL;
-  struct gdbarch *reply_arch = NULL;
   ULONGEST addr;
   const char *p;
   int skipregs = 0;
@@ -7048,11 +7050,11 @@ Packet: '%s'\n"),
 			  continue;
 			}
 
-		      reply_arch = inf->gdbarch;
-		      rsa = get_remote_arch_state (reply_arch);
+		      event->arch = inf->gdbarch;
+		      rsa = get_remote_arch_state (event->arch);
 		    }
 
-		  struct packet_reg *reg = packet_reg_from_pnum (reply_arch,
+		  struct packet_reg *reg = packet_reg_from_pnum (event->arch,
 								 rsa, pnum);
 		  cached_reg_t cached_reg;
 
@@ -7063,13 +7065,13 @@ Packet: '%s'\n"),
 
 		  cached_reg.num = reg->regnum;
 		  cached_reg.data = (gdb_byte *)
-		    xmalloc (register_size (reply_arch, reg->regnum));
+		    xmalloc (register_size (event->arch, reg->regnum));
 
 		  p = p1 + 1;
 		  fieldsize = hex2bin (p, cached_reg.data,
-				       register_size (reply_arch, reg->regnum));
+				       register_size (event->arch, reg->regnum));
 		  p += 2 * fieldsize;
-		  if (fieldsize < register_size (reply_arch, reg->regnum))
+		  if (fieldsize < register_size (event->arch, reg->regnum))
 		    warning (_("Remote reply is too short: %s"), buf);
 
 		  VEC_safe_push (cached_reg_t, event->regcache, &cached_reg);
@@ -7285,7 +7287,7 @@ process_stop_reply (struct stop_reply *stop_reply,
       if (stop_reply->regcache)
 	{
 	  struct regcache *regcache
-	    = get_thread_arch_regcache (ptid, target_gdbarch ());
+	    = get_thread_arch_regcache (ptid, stop_reply->arch);
 	  cached_reg_t *reg;
 	  int ix;
 
-- 
2.5.5