CONFIG_DEBUG_EXTRA_FLAGS is not available for thedefaultarchitecture x86.
Result is shown for architecture tile
default or selected kernelversion does not have config value CONFIG_DEBUG_EXTRA_FLAGS.
Result is shown for kernelversion 6.2.5

Additional compiler arguments when building with '-g'


Linux Kernel Configuration
└─>Kernel hacking
└─>Additional compiler arguments when building with '-g'
In linux kernel since version 2.6.36 (release Date: 2010-10-20)  
Debug info can be large, and flags like
`-femit-struct-debug-baseonly' can reduce the kernel file
size and build time noticeably. Such flags are often
helpful if the main use of debug info is line number info.