Eclipse error with command gdb

If you work on a Mac OS X 10.9 Mavericks or later, you will run into
the problem of Eclipse refusing to interactively debug problems that
otherwise build and run fine:
An attempt to start a debugging session by selecting

from the menu will result in Eclipse complaining that an
Error with command: gdb —version
has occurred.

The problem is caused by Apple switching away from GDB, the GNU
debugger, to LLDB, the LLVM debugger, in their Xcode toolchain (along
with the transition from GCC to Clang). Unfortunately, Eclipse is not
capable of communicating with any debugger other than GDB (yet).
Here is a step-by-step guide for installing and configuring GDB.

Installing GDB

As with GCC, the easiest way to install GDB is through Homebrew.
In a Terminal window, run the command
brew install gdb,
and wait for it to complete.
(As usual, it may ask for your password.)

Now, we need to code-sign the GDB executable, so it will be allowed to
control other processes, as necessary for a debugger.
For that, we will first create a new certificate in Keychain.

Creating a Certificate

Open the Keychain Access application (can be found in
Applications/Utilities directory or through Spotlight).
Select in the application menu
().
An assistant window will appear for guiding you through the process.

1. First, you will be asked for the name and type of the certificate.
   You may choose the name arbitrarily, but to simplify its future use in
   command line, prefer names without spaces or other fancy characters,
   e.g., gdbcert.
2. Make sure that
   is set to ,
   change
   to ,
   check the
   checkbox, and click .
   Click again in the popup
   prompt warning about the certificate being self-signed.
3. On the next page, leave
   to be 1, and set
   to a large enough number of days to cover the duration of the class
   or more, say, 365.
   (Certificates cannot last forever; the maximum validity period
   is 20 years.)
4. Then click once again, and keep
   doing so to skip the next six screens until you see the one entitled
   .
   For the only property, , choose
   from the drop-down list.
   Lastly, click , type in your
   password, if prompted, and click .
5. Back in the main window, choose the
   keychain in the sidebar on the left, and select the newly created
   certificate from the list.
   Open the context menu and select
   .
   In the information window that will appear, expand the
   section and set the
   property to
   .
   Close this window (you may be asked for your password),
   and quit Keychain Access.

Signing GDB

Our new certificate is now ready to be used.
In order to make it immediately available for signing, we need to
restart the Taskgate access-control service.
You can use Activity Monitor to do this (also found in
Applications/Utilities).
Open it and filter the list of processes by typing
taskgated in the search field in the toolbar.
(If you cannot find it, make sure the menu item is checked.)

There should be exactly one process left in the list.
Highlight it, then select

from the menu, and click
in the popup prompt.
The Taskgate process will be terminated and, consequently, should
disappear from the list.
In a few seconds, it will be restarted by the system and should
reappear in the list. Please wait for this to happen (it may take up to
a minute or two, at worst).

Finally, in a Terminal window, run
codesign -s gdbcert /usr/local/bin/gdb
(if you named your certificate differently, replace
gdbcert with its name here).
Once again, you will be prompted for you username and password.
If the command does not produce any output, then GDB is
successfully signed.

Configuring Eclipse

The only thing left to do is to point Eclipse to the GDB executable.
Open from the
main menu (not to be confused with
).
In the tree of options listed in the sidebar, navigate to
, and set
the field to
/usr/local/bin/gdb.

If there is no section
in the subtree,
close the preferences window, and try to first start a debugging
session for any project that you can already run without problems.
You can do it by either clicking the
button on the toolbar, or selecting
from the main menu.
This attempt will, of course, fail with an error message about
the gdb command, but it will force
the said
settings to appear in the preferences.

This will change the GDB executable for new projects; for all existing
ones (that you are going to use debugging for), you will need to
manually update their debug configurations.
To do that, select

from the menu.
In the window that appears, one after another, select every project
under the section in
the sidebar.
For each of them, open the tab,
set the field to the same path
/usr/local/bin/gdb, and click the
button.
After repeating this change for all listed projects, click .

❦

If the above steps do not solve the issue on your machine, or you
encounter a problem while following them, please do not hesitate to
come to one of the upcoming common labs for help.