__fortify_panic() question

[Jeff Johnson <quic_jjohnson@quicinc.com>]

'make W=1 C=1' on x86 gives the warning:
arch/x86/boot/compressed/misc.c:535:6: warning: symbol '__fortify_panic' was not declared. Should it be static?

Looking at this I see for ARM there is a prototype for __fortify_panic() in
arch/arm/boot/compressed/misc.h
And there is a matching implementation in arch/arm/boot/compressed/misc.c

But for x86 there is only the implementation in
arch/x86/boot/compressed/misc.c
There is not a prototype in arch/x86/boot/compressed/misc.h.

The easy fix for this would be to add a prototype to
arch/x86/boot/compressed/misc.h.

But it seems strange to me to add a prototype to a header file that is only 
for the benefit of the callee and is not the prototype/header used by the 
caller, in this case the one in include/linux/fortify-string.h

Is there a reason this prototype can't be defined in a single header file that 
is then included by all callers and callees?

/jeff