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AR# 18703

10.1 EDK - Unable to launch GDB; an error message occurs: "Cannot find a usable main.tcl"


When I try to launch GDB from within an XPS project (i.e., Debug -> Launch software debugger), it fails to launch the GNU debugger. This problem occurs for various projects, and the following error message appears:

"Can't find a usable main.tcl in the following directories......"

The tools proceed to list a number of directories in the GDB install directory of EDK:



The GDB initialization files no longer match the current setup.

The following are possible resolutions for this problem.

You can still launch the debugger from a Cygwin shell because the Cygwin shell does not use the GDB initialization files:

1. In XPS, select the Project pull-down menu and select "Launch EDK shell."

2. In the Cygwin shell, enter:

powerpc-eabi-gdb -nx

You can delete the initialization files so that GDB can be launched from the GUI:

1. Open a Cygwin shell.

2. Enter the command:

cd $HOME

3. Enter the command:

rm gdbtk.ini

Some home directories contain .gdb* files that can also be removed.

XMD/GDB rely on Tcl. Other software tools that set the TCL_LIBRARY and TK_LIBRARY environment variables can cause GDB to behave improperly. You can remove or change the TCL_LIBRARY and TK_LIBRARY environment variables.

AR# 18703
Date Created 09/03/2007
Last Updated 12/15/2012
Status Active
Type General Article