[patch] Suggest fixing your target for gdbserver(1)

[Jan Kratochvil <jan.kratochvil@redhat.com>]

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Hi,

x86_64 defaults (by bfd matching) to target "i386" instead of its native
"i386:x86_64".  Therefore if you connect to gdbserver(1) without any `file' or
`set architecture' command before the communication will crash on a different
expected register sizes.

As implementing architecture negotiation is complicated due to gdbserver(1) not
being aware of bfd-compatible name of its target and also it may be also
unclear to automatically change the target while working remotely it is just
suggesting to double-check which architecture you are using.


(gdb) target remote localhost:1234
Remote debugging using localhost:1234
Remote debugging from host 127.0.0.1
Remote register badly formatted: T0506:0000000000000000;07:40daffbf7f000000;10:506b55952a000000;
readchar: Got EOF
here: 0000000;07:40daffbf7f000000;10:506b55952a000000;
Try to load the executable by `file' first,
you may also check `set/show architecture'.
(gdb) Remote side has terminated connection.  GDBserver will reopen the connection.
Listening on port 1234



Regards,
Jan

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2006-09-26  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* remote.c (remote_wait): Suggestion on crash due to nonmatching target.
	(remote_async_wait): Likewise.


Index: gdb/remote.c
===================================================================
RCS file: /cvs/src/src/gdb/remote.c,v
retrieving revision 1.230
diff -u -p -r1.230 remote.c
--- gdb/remote.c	22 Sep 2006 13:50:36 -0000	1.230
+++ gdb/remote.c	26 Sep 2006 15:15:32 -0000
@@ -3103,8 +3103,13 @@ Packet: '%s'\n"),
 					 reg->regnum, regs);
 		  }
 
+		/* It may also occur on amd64 which defaults to 32-bit i386
+		   target.  gdbserver(1) is not aware of the `set architecture'
+		   name itself as it is not using libbfd.  */
 		if (*p++ != ';')
-		  error (_("Remote register badly formatted: %s\nhere: %s"),
+		  error (_("Remote register badly formatted: %s\nhere: %s"
+			   "\nTry to load the executable by `file' first,"
+			   "\nyou may also check `set/show architecture'."),
 			 buf, p);
 	      }
 	  }
@@ -3299,8 +3304,13 @@ Packet: '%s'\n"),
 		    regcache_raw_supply (current_regcache, reg->regnum, regs);
 		  }
 
+		/* It may also occur on amd64 which defaults to 32-bit i386
+		   target.  gdbserver(1) is not aware of the `set architecture'
+		   name itself as it is not using libbfd.  */
 		if (*p++ != ';')
-		  error (_("Remote register badly formatted: %s\nhere: %s"),
+		  error (_("Remote register badly formatted: %s\nhere: %s"
+			   "\nTry to load the executable by `file' first,"
+			   "\nyou may also check `set/show architecture'."),
 			 buf, p);
 	      }
 	  }