Xcode offers two command-line debuggers: gdb and lldb. The LLDB project (hosted at http://llvm.org) expands upon the standard GNU debugger (gdb) with improved memory efficiency and Clang compiler integration.
The LLVM project is an open source collection of tools (see LLVM.org for the full list) that build on a core set of libraries that provide an optimizer and code generator. Other tools in the LLVM project include the Clang frontend parser and the LLDB debugger. Xcode 4 exploits this modular approach to provide features such as improved syntax highlighting and to suggest fixes to common coding errors.
Here are several debugging tutorial of LLDB
The LLVM project is an open source collection of tools (see LLVM.org for the full list) that build on a core set of libraries that provide an optimizer and code generator. Other tools in the LLVM project include the Clang frontend parser and the LLDB debugger. Xcode 4 exploits this modular approach to provide features such as improved syntax highlighting and to suggest fixes to common coding errors.
Here are several debugging tutorial of LLDB