I have a project for Mac OS X 10.5 that I'm building on 10.6 using Xcode 3.2. When I use GCC 4.2 for Debug build and hit a breakpoint, Xcode debugger displays local variable information normally. If I choose LLVM GCC 4.2 or Clang LLVM, when I hit breakpoint, local symbols are not available, and GDB says No symbol 'self' in current context if I try to print self or any other local symbol. In all cases Generate debug info option is set. The Debug configuration is set to $(NATIVE_ARCH) and 10.5 SDK, Build active architecture only option is set. When GDB starts, I can see it is being configured as x86_64-apple-darwin. I must be missing something obvious. How do I make GDB show local symbols when using a LLVM compiler?