https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106560
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
<source>:4:1: warning: data definition has no type or storage class
4 | a;
| ^
<source>:4:1: warning: type defaults to 'int' in declaration of 'a'
[-Wimplicit-int]
<source>:4:1: error: conflicting types for 'a'; have 'int'
<source>:2:8: note: previous declaration of 'a' with type 'void **'
2 | void **a;
| ^
<source>: In function 'b':
<source>:3:19: internal compiler error: tree check: expected class 'type', have
'exceptional' (error_mark) in useless_type_conversion_p, at gimple-expr.cc:87
3 | void b() { void **c = a; }
| ^
0x200570e internal_error(char const*, ...)
???:0
0x84a7cf tree_class_check_failed(tree_node const*, tree_code_class, char
const*, int, char const*)
???:0
0xd1be13 gimplify_expr(tree_node**, gimple**, gimple**, bool (*)(tree_node*),
int)
???:0
0xd1f84a gimplify_stmt(tree_node**, gimple**)
???:0
0xd1bf27 gimplify_expr(tree_node**, gimple**, gimple**, bool (*)(tree_node*),
int)
???:0
0xd1f84a gimplify_stmt(tree_node**, gimple**)
???:0
0xd1c7fe gimplify_expr(tree_node**, gimple**, gimple**, bool (*)(tree_node*),
int)
???:0
0xd1f84a gimplify_stmt(tree_node**, gimple**)
???:0
0xd20ed3 gimplify_body(tree_node*, bool)
???:0
0xd2131f gimplify_function_tree(tree_node*)
???:0
0xb5a2d7 cgraph_node::analyze()
???:0
0xb5dd91 symbol_table::finalize_compilation_unit()
???:0
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
Compiler returned: 1
