[Bug fortran/105691] Incorrect calculation of INDEX(str1,str2) at compile time

[anlauf at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105691

--- Comment #5 from anlauf at gcc dot gnu.org ---
Submitted version: https://gcc.gnu.org/pipermail/fortran/2022-June/057940.html