[Bug fortran/96041] [11 regression] ICE in gfortran.dg/pr93423.f90 after r11-1792

[anlauf at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96041

--- Comment #4 from anlauf at gcc dot gnu.org ---
(In reply to Dominique d'Humieres from comment #3)
> From several runs
> 
>     frame #0: 0x00000001000f11ed f951`gfc_free_namespace(gfc_namespace*)
> [inlined] free_uop_tree(uop_tree=0x00000000000000ce) at symbol.c:3881:17
>     frame #0: 0x00000001000f0b27 f951`::free_sym_tree(gfc_symtree *)
> [inlined] free_sym_tree(sym_tree=0x00000000000000ce) at symbol.c:3899:17
> 
> It seems that some trees are not built properly.

I set breakpoints in gdb in these routines but see nothing special on x86_64.

Maybe some stack/heap corruption issue affecting ref counts?