[Bug c/106764] [12/13 Regression] ICE on invalid code in tree check: expected function_type or method_type, have error_mark in gimplify_call_expr, at gimplify.cc

["pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106764

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
At the point where the CALL_EXPR is built:
Breakpoint 5, build_function_call_vec (loc=258624, arg_loc=...,
function=<var_decl 0x7ffff7251cf0 a>, params=0x0, origtypes=0x0,
orig_fundecl=<tree 0x0>) at
/home/apinski/src/upstream-gcc/gcc/gcc/c/c-typeck.cc:3250
3250      fntype = TREE_TYPE (function);

function is:
(gdb) p debug_tree(function)
 <var_decl 0x7ffff7251cf0 a
    type <pointer_type 0x7ffff73e5930
        type <function_type 0x7ffff726e9d8 type <integer_type 0x7ffff72615e8
int>
            QI
            size <integer_cst 0x7ffff7242e88 constant 8>
            unit-size <integer_cst 0x7ffff7242ea0 constant 1>
            align:8 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0x7ffff726e9d8
            pointer_to_this <pointer_type 0x7ffff73e5930>>
        unsigned DI
        size <integer_cst 0x7ffff7242d98 constant 64>
        unit-size <integer_cst 0x7ffff7242db0 constant 8>
        align:64 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0x7ffff73e5930>
    used public static unsigned read DI defer-output t.c:1:3 size <integer_cst
0x7ffff7242d98 64> unit-size <integer_cst 0x7ffff7242db0 8>
    align:64 warn_if_not_align:0>

And the type is fine.
And then the code in duplicate_decls goes and replaces the type to be
error_mark_node.
And then we don't check for error_mark_node later on during gimplification.

Trying to figure out the best place to put the check for error_mark_node now.


Note while looking into the gimplification code, I found some odd looking code
dealing with the location so I filed PR 107737.