Fix most Coverity Scan performance warnings

[rouault]

No description provided.

[jjimenezshaw]

Now I am curious. Were there performance warnings due to the lack of const?

[rouault]

Now I am curious. Were there performance warnings due to the lack of const?

not directly. But Coverity Scan insists on using std::move() as much as possible. But in some places, I find it a bit dangerous, because it is not immediately obvious that the variable might not be used afterwards. Adding const makes the variable non-moveable, hence std::move() can't be used and the copy assignment operator is used.

I don't believe any of those "fixes" are going to have measurable perf improvements. The main goal is to shut off Coverity Scan.

[jjimenezshaw]

Than makes sense. Thanks!