tree-wide: fix a pile of lints

This:
- Converts a bunch of C style casts into C++ casts.
- Removes some very silly pointer subtraction code (which is no more or
  less busted on i686 than it began)
- Fixes some "technically UB" that never had to be UB in the first
  place.
- Makes finally follow the noexcept status of the inner function. Maybe
  in the future we should ban the function from not being noexcept, but
  that is not today.
- Makes various locally-used exceptions inherit from std::exception.

Change-Id: I22e66972602604989b5e494fd940b93e0e6e9297

1 files changed, 1 insertions, 1 deletions

diff --git a/src/libutil/finally.hh b/src/libutil/finally.hh
index cbfd6195b..dc51d7b1e 100644
--- a/src/libutil/finally.hh
+++ b/src/libutil/finally.hh
@@ -22,7 +22,7 @@ public:
     Finally(Finally &&other) : fun(std::move(other.fun)) {
         other.movedFrom = true;
     }
-    ~Finally() noexcept(false)
+    ~Finally() noexcept(noexcept(fun()))
     {
         try {
             if (!movedFrom)