debug-optimized-builds

GDB shows <optimized out> because compiler optimizations remove or relocate variables from registers. Debugging optimized builds requires using flags like -Og or split DWARF to preserve enough debug info to inspect values.

Debugging optimized code in a release build is possible by using the -Og flag, which applies optimizations that still allow GDB to inspect variables. You can also use -gsplit-dwarf to separate debug info for faster linking.

The -Og flag is the best compiler flag for debugging optimized C++ code because it optimizes without hindering the debugging experience. It provides a balance between performance and debuggability compared to -O2.

To step through inlined functions during optimized debugging, use GDB commands designed to navigate inlined frames. The compiler inlines functions for performance, but GDB can still inspect the code if compiled with appropriate debug flags.

Split DWARF helps with debugging optimized release builds by moving debug information into separate files. This reduces linker times and speeds up the build process while still providing the necessary debug data for GDB.

Line number discrepancies in RelWithDebInfo builds happen because optimizations reorder code. You can navigate these discrepancies in GDB by understanding how compiler optimizations affect source line mapping during optimized debugging.