DMD internal: appendToModuleMember performance

[Walter Bright via Digitalmars-d]

On 4/22/2016 2:38 PM, Johan Engelen wrote:
> I don't understand exactly what you mean; do you propose to resort to linear
> search after a removal happened? Or only do a linear search when the shadow data
> structure says the item is present?
> I don't know how often removals happen, but for the 140k elements list removals
> happens _very_ often. While compiling phobos, removals happen not for all
> modules, but for quite a few of them.

I did a grep for "members.remove" and got no hits. Where are the removes happening?