On Wed, Jul 22, 2026 at 09:06:58AM +0200, Richard Biener wrote:
> That said, I also believe trying to get tree more strongly typed using C++
> is not going to be an improvement. That might be the fault of C++ though.
>
> Possibly doing sth like
>
> extern tree fold_build2_loc (location_t, enum tree_code, tree_type, tree,
> tree CXX_MEM_STAT_INFO);
>
> with checking-enabled tree_type expanding to assertion (but otherwise just
> being a no-op wrapper), and possibly allowing type assertions and/or
> automatic annotation for static analysis might be an improvement?
Usually something inside of fold_build2_loc actually accesses some
properties of the type and type checking triggers there. So, by moving
that check earlier, all we'd achieve is to assert one or two frames up
in the callstack.
With types vs. non-types, there is also the complication what is
error_mark_node, currently we treat it as both expression and type, but
with limited usability, TREE_TYPE (error_mark_node) is error_mark_node.
Jakub
