> Ada is the last user of the tree_exp->complexity field. Removing > this field should reduce GCC's memory usage by about 5% on a 64 bit > host. Could an Ada maintainer see if it possible to remove the use > of this field? I would think it shouldn't be too hard -- > TREE_COMPLEXITY is used only inside ada/decl.c. But I haven't been > able to figure out myself yet how to avoid using TREE_COMPLEXITY there...
It's just being used as a cache to avoid recomputing a value. My suggestion would be to replace it with a hash table. It'll tend to keep nodes around a little more than usual, but that should be a tiny cost.
