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Strange behaviour using Cygwin GDB with Linux GDBServer


I am seeing some strange behavior while using Cygwin GDB and connecting
to a remote machine via TCP/IP running Linux and GDBServer.

The machine running Cygwin is a P4 with Windows 2000, I do have
Administer privileges. The version of GDB is 2003-03-03-cvs
(cygwin-special), and I have also downloaded and compiled GDB version
5.2, with the same results.
The machine running the GDBServer is a P3 embedded headless unit. I
believe the GDBServer version is 5.5-2. I do know the kernel version is
2.4.18-3. I cannot run GDB locally on this machine.
The GDB remote protocol is running over TCP/IP.

Since this is a work project I am limited in how specific the
information on the systems and software is

What I am seeing is the following error message in GDB every time a
breakpoint is hit:
Remote packet too long:
0500000037000000100000000c831d4090faffbf28fbffbf20200140
b4fcffbf35070d0846020000230000002b0000002b0000002b000000000000000000000000000000
00000000ffff0000000000000000ffff0000000000000000ffff0000000000000000ffff00000000
00000000ffff0000000000000000ffff0000000000000080ff3f0000000000000080ffbf7f030000
20000000ffff00002300000018a70e082b00000090d6ffbf5d030000000000000000000000000000
0000000000000000000000
Remote packet too long:
0500000037000000100000000c831d4090faffbf28fbffbf20200140
b4fcffbf35070d0846020000230000002b0000002b0000002b000000000000000000000000000000
00000000ffff0000000000000000ffff0000000000000000ffff0000000000000000ffff00000000
00000000ffff0000000000000000ffff0000000000000080ff3f0000000000000080ffbf7f030000
20000000ffff00002300000018a70e082b00000090d6ffbf5d030000000000000000000000000000
0000000000000000000000
Remote packet too long:
0500000037000000100000000c831d4090faffbf28fbffbf20200140
b4fcffbf35070d0846020000230000002b0000002b0000002b000000000000000000000000000000
00000000ffff0000000000000000ffff0000000000000000ffff0000000000000000ffff00000000
00000000ffff0000000000000000ffff0000000000000080ff3f0000000000000080ffbf7f030000
20000000ffff00002300000018a70e082b00000090d6ffbf5d030000000000000000000000000000
0000000000000000000000
Ignoring packet error, continuing...
Remote packet too long:
0500000037000000100000000c831d4090faffbf28fbffbf20200140
b4fcffbf35070d0846020000230000002b0000002b0000002b000000000000000000000000000000
00000000ffff0000000000000000ffff0000000000000000ffff0000000000000000ffff00000000
00000000ffff0000000000000000ffff0000000000000080ff3f0000000000000080ffbf7f030000
20000000ffff00002300000018a70e082b00000090d6ffbf5d030000000000000000000000000000
0000000000000000000000

At the same time I see the following message from the GDBserver:
gdb: Wrong sized register packet (expected 624 bytes, got 352)

If I run Linux GDB version 5.2-2 this behavior does not appear.

The command "show remote memory-write-packet-size" displays the
following results:
Cygwin:  The memory-write-packet-size is 0. Packets are limited to 399
bytes.
Linux: The memory-write-packet-size is 0. Packets are limited to 656 bytes.

From what I understand Linux and Cygwin are definning different sized
register packets. Which is why Cygwin<->Linux shows the behavior while
Linux<->Linux does not. What I can't figure out is why the register
packets are different and/or how to change the Cygwin GDB to use the
larger packets. I do not have the option of changing the GDBServer.

I can't find an answer to this in either the mailing list archives or on
the web. The closest I found was regarding a cross platform register
misdefinition.

I would greatly appreciate it if someone could A. tell me the settings
for GDB to use the larger packet size, B. give me a patch for GDB, C.
give me the information for me to patch my own copy of GDB.

I did attempt to run cygcheck as described in the mailing list faq,
however it exited with an error message:
$ cygcheck -s -v -r > cygcheck.out
cygcheck: dump_sysinfo: GetVolumeInformation() failed: 1005

- Michael



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