For a large c/C++ code base, I use an editor called SourceInsight. This is the most invaluable tool for navigating code I've come across in my 3 year career as a software developer. I work in a very large software company, and there are several code bases running into millions of lines of C/C++ code. My previous team had 60,000+ files, with the largest file being about 12k loc.
If you have access to logs from a production service / component, I find TextAnalyzer.net quite invaluable. I take an example 500 mb log dump - opened in TextAnalyzer.net and just scroll through the logs (often jumping, following code paths etc), while keeping the source code side by side. This allows me to understand the execution flow, and is typically faster than attaching a debugger. If it's a multi-threaded program, the debugger is hard to work with - and logs are your best friend. You are lucky if the log has thread information (like threadId etc)
If you have access to logs from a production service / component, I find TextAnalyzer.net quite invaluable. I take an example 500 mb log dump - opened in TextAnalyzer.net and just scroll through the logs (often jumping, following code paths etc), while keeping the source code side by side. This allows me to understand the execution flow, and is typically faster than attaching a debugger. If it's a multi-threaded program, the debugger is hard to work with - and logs are your best friend. You are lucky if the log has thread information (like threadId etc)