Though there is g++/gcc in Xcode 8, gdb isn't found When I installed command line tools of Xcode in old Mac OS X,
there were g++/gcc of a compiler and a linker.
There was also gdb of a debugger.

In Xcode 8.0 (8A218a) of Mac OSX EI Captain (10.11.6),
there are g++ and gcc, but gdb isn't found.
I'd like to use a debugger of a command line tool.
Is there a debug command? If there is, please tell me.

When the g++/gcc [-c] .c/.cpp -g is executed before,
*.o and executable format (a.out) seem to have included all symbol information.
When g++/gcc [-c] .c/.cpp -g makes executable format (a.out)
in case of Xcode 8.0 (8A218a) of Mac OS X EI Captain (10.11.6),
a directory called a.out.dSYM is made at the same directory,
and symbol information seems to be here.

When there are no debug command line tool,
if it's possible to debug a program by a GUI of Xcode in IDE,
please tell me the way.

Regards
The command-line debugger in Xcode is now LLDB; the relevant command is lldb.