default or selected kernelversion does not have config value CONFIG_OPTIMIZE_INLINING.
Result is shown for kernelversion 6.9.5

Allow gcc to uninline functions marked 'inline'


Linux Kernel Configuration
└─>Kernel hacking
└─>Allow gcc to uninline functions marked 'inline'
In linux kernel since version 2.6.26 (release Date: 2008-07-13)  
This option determines if the kernel forces gcc to inline the functions
developers have marked 'inline'. Doing so takes away freedom from gcc to
do what it thinks is best, which is desirable for the gcc 3.x series of
compilers. The gcc 4.x series have a rewritten inlining algorithm and
enabling this option will generate a smaller kernel there. Hopefully
this algorithm is so good that allowing gcc 4.x and above to make the
decision will become the default in the future. Until then this option
is there to test gcc for this.

If unsure, say N.