Git help requested: "git stash pop" is doing an unwanted "git add". Why?

[Alan Mackenzie]

Hello, Emacs.

I'm clearing out a "stash stack" in my master repository copy.  I've
just done "git stash pop", expecting git to pop the changes into my
working directory.

Well, there were 2 files with conflicts - fair enough.  But with all the
other files, git has had the cheek to do a "git add" (I think the jargon
for this is "moved the files to the staging area"), leaving me with the
hassle of doing a "git reset" on quite a lot of files.

Why has the "git stash pop" done this, and how can I call "git stash
pop" in the future, avoiding this annoying problem?

-- 
Alan Mackenzie (Nuremberg, Germany).