BRN:Software:Build and Distribution:Userland Debugging - Revision history

Holger: /* Debug Setup */

2007-04-22T10:57:10Z

Debug Setup

← Older revision		Revision as of 10:57, 22 April 2007
Line 1:		Line 1:
	= Debug Setup =		= Debug Setup =

	The remove debugging setup consists of a debugger stub (named gdbserver), which runs on the target machine (mipsel in our case) and is attached to the debuggee process. The debugger resists on a (~~remove~~) host machine and is connectet to the stub via a TCP/IP or serial connection. At first we have to build both a debugger stub and a cross-debugger (note that the host debugger which is shipped with the linux distribution could not be used for cross debugging).		The remove debugging setup consists of a debugger stub (named gdbserver), which runs on the target machine (mipsel in our case) and is attached to the debuggee process. The debugger resists on a (remote) host machine and is connectet to the stub via a TCP/IP or serial connection. At first we have to build both a debugger stub and a cross-debugger (note that the host debugger which is shipped with the linux distribution could not be used for cross debugging).

	* Build the gdbserver. It must be configured for host and target mipsel.		* Build the gdbserver. It must be configured for host and target mipsel.

Jkm: /* FAQ */

2007-02-01T10:47:02Z

FAQ

← Older revision		Revision as of 10:47, 1 February 2007
Line 45:		Line 45:

	A: You need to build the libraries without running sstrip, which removes all symbols from the binary to reduce size. See [http://forum.openwrt.org/viewtopic.php?pid=19195]		A: You need to build the libraries without running sstrip, which removes all symbols from the binary to reduce size. See [http://forum.openwrt.org/viewtopic.php?pid=19195]

			With the OpenWRT distribution (Kamikaze), you have to replace STRIP in 'rules.mk': E.g. set STRIP to
			<pre>
			STRIP:=/bin/echo
			</pre>

Jkm: /* FAQ */

2007-02-01T08:57:31Z

FAQ

← Older revision		Revision as of 08:57, 1 February 2007
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	Loaded symbols for /openwrtroot/lib/ld-uClibc.so.0		Loaded symbols for /openwrtroot/lib/ld-uClibc.so.0
	</pre>		</pre>
	for some libraries. ~~Further I get~~		for some libraries.
	<pre>
	Remote debugging using wgt71:2000
	0x2acece24 in ?? ()
	warning: Unable to find dynamic linker breakpoint function.
	GDB will be unable to debug shared library initializers
	and track explicitly loaded dynamic code.
	</pre>
	when starting remote debugging via 'target remote wgt71:2000'.

	A: You need to build the libraries without running sstrip, which removes all symbols from the binary to reduce size. See [http://forum.openwrt.org/viewtopic.php?pid=19195]		A: You need to build the libraries without running sstrip, which removes all symbols from the binary to reduce size. See [http://forum.openwrt.org/viewtopic.php?pid=19195]

Jkm: /* FAQ */

2007-02-01T07:55:25Z

FAQ

← Older revision		Revision as of 07:55, 1 February 2007
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	= FAQ =		= FAQ =

			* Q: I run 'set solib-absolute-prefix /openwrtroot/' and get
	* Error Message "..." during ...
			<pre>
	* A: ...
			Reading symbols from /openwrtroot/lib/libgcc_s.so.1...warning: no loadable sections found in added symbol-file /openwrtroot/lib/libgcc_s.so.1
			done.
			Loaded symbols for /openwrtroot/lib/libgcc_s.so.1
			Reading symbols from /openwrtroot/lib/libc.so.0...warning: no loadable sections found in added symbol-file /openwrtroot/lib/libc.so.0
			done.
			Loaded symbols for /openwrtroot/lib/libc.so.0
			Reading symbols from /openwrtroot/lib/ld-uClibc.so.0...warning: no loadable sections found in added symbol-file /openwrtroot/lib/ld-uClibc.so.0
			done.
			Loaded symbols for /openwrtroot/lib/ld-uClibc.so.0
			</pre>
			for some libraries. Further I get
			<pre>
			Remote debugging using wgt71:2000
			0x2acece24 in ?? ()
			warning: Unable to find dynamic linker breakpoint function.
			GDB will be unable to debug shared library initializers
			and track explicitly loaded dynamic code.
			</pre>
			when starting remote debugging via 'target remote wgt71:2000'.

			A: You need to build the libraries without running sstrip, which removes all symbols from the binary to reduce size. See [http://forum.openwrt.org/viewtopic.php?pid=19195]

Kurth at 07:30, 1 February 2007

2007-02-01T07:30:19Z

← Older revision		Revision as of 07:30, 1 February 2007
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	Now you should be able to use the remote debugger in the same was as a local debugger.		Now you should be able to use the remote debugger in the same was as a local debugger.

			= FAQ =

			* Error Message "..." during ...
			* A: ...

Jkm: Adjusted libraries for OpenWRT

2007-01-28T06:37:02Z

Adjusted libraries for OpenWRT

← Older revision		Revision as of 06:37, 28 January 2007
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	It may be the case that the gdb does not find the images of the linked-in shared libraries, since host and target system may differ. As a result, the debugger is not able to exermine the stack correctly and no (of no usefull) backtrace could be generated. You can solve this problem by specifying a shared object lookup prefix using the following command:		It may be the case that the gdb does not find the images of the linked-in shared libraries, since host and target system may differ. As a result, the debugger is not able to exermine the stack correctly and no (of no usefull) backtrace could be generated. You can solve this problem by specifying a shared object lookup prefix using the following command:

	(gdb) set solib-absolute-prefix /~~wgtroot~~		(gdb) set solib-absolute-prefix /openwrtroot/gdb/lib

	This '''must''' be done every time you attach to a process.		This '''must''' be done every time you attach to a process.

Jkm: /* Debugging Userland Applications */

2006-10-06T15:45:07Z

Debugging Userland Applications

← Older revision		Revision as of 15:45, 6 October 2006
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	(gdb) set solib-absolute-prefix /wgtroot		(gdb) set solib-absolute-prefix /wgtroot

			This '''must''' be done every time you attach to a process.

	Now you should be able to use the remote debugger in the same was as a local debugger.		Now you should be able to use the remote debugger in the same was as a local debugger.

Kurth at 10:43, 4 October 2006

2006-10-04T10:43:45Z

← Older revision		Revision as of 10:43, 4 October 2006
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	* Build the cross-gdb. Configure it for target mipsel and host i386.		* Build the cross-gdb. Configure it for target mipsel and host i386.

	Precompiled binaries could be found in the NFS rootfs and in /usr/local/bin on nfs-student.		Precompiled binaries could be found in the NFS rootfs and in /usr/local/bin/mipsel-linux-uclibc-gdb on nfs-student.

	= Debugging Userland Applications =		= Debugging Userland Applications =

Kurth at 10:43, 4 October 2006

2006-10-04T10:43:17Z

← Older revision		Revision as of 10:43, 4 October 2006
Line 5:		Line 5:
	* Build the gdbserver. It must be configured for host and target mipsel.		* Build the gdbserver. It must be configured for host and target mipsel.
	* Build the cross-gdb. Configure it for target mipsel and host i386.		* Build the cross-gdb. Configure it for target mipsel and host i386.

			Precompiled binaries could be found in the NFS rootfs and in /usr/local/bin on nfs-student.

	= Debugging Userland Applications =		= Debugging Userland Applications =

Kurth at 10:11, 27 September 2006

2006-09-27T10:11:43Z

← Older revision		Revision as of 10:11, 27 September 2006
Line 3:		Line 3:
	The remove debugging setup consists of a debugger stub (named gdbserver), which runs on the target machine (mipsel in our case) and is attached to the debuggee process. The debugger resists on a (remove) host machine and is connectet to the stub via a TCP/IP or serial connection. At first we have to build both a debugger stub and a cross-debugger (note that the host debugger which is shipped with the linux distribution could not be used for cross debugging).		The remove debugging setup consists of a debugger stub (named gdbserver), which runs on the target machine (mipsel in our case) and is attached to the debuggee process. The debugger resists on a (remove) host machine and is connectet to the stub via a TCP/IP or serial connection. At first we have to build both a debugger stub and a cross-debugger (note that the host debugger which is shipped with the linux distribution could not be used for cross debugging).

			* Build the gdbserver. It must be configured for host and target mipsel.
	* Build the
			* Build the cross-gdb. Configure it for target mipsel and host i386.

	= Debugging Userland Applications =		= Debugging Userland Applications =

			* At first, start the gdbserver on the mips. You can either specify an executable which is load or attach it to a running process. To debug a process with PID 333 for example, simply type

			wgt30$ gdbserver :2000 --attach 333

			The debugger stub is now attached to the process with given PID and reachable on TCP port 2000.

			* Start the cross-debugger on the host system and connect it to the stub, e.g.

			(gdb) target remote wgt30:2000

			It may be the case that the gdb does not find the images of the linked-in shared libraries, since host and target system may differ. As a result, the debugger is not able to exermine the stack correctly and no (of no usefull) backtrace could be generated. You can solve this problem by specifying a shared object lookup prefix using the following command:

			(gdb) set solib-absolute-prefix /wgtroot

			Now you should be able to use the remote debugger in the same was as a local debugger.