Annex G (informative) Ill-formed, no diagnostic required [ifndr]

G.6 [dcl]: Declarations [ifndr.dcl]

G.6.1[ifndr:dcl.constinit.specifier.not.reachable]
Specified in: [dcl.constinit]

1
#
If the initializing declaration of a variable without the constinit specifier has the constinit specifier applied to declarations that are not reachable from that initializing declaration, the program is ill-formed, no diagnostic required.
2
#
[Example 1: 

Translation unit #1:int x = 5; // initializing declaration of x

Translation unit #2:extern constinit int x; // IFNDR, not reachable from initializing declaration of x — end example]