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, 2 insertions, 1 deletions

diff --git a/src/libutil/strings.cc b/src/libutil/strings.cc
index df48e9203..de9a0eb9f 100644
--- a/src/libutil/strings.cc
+++ b/src/libutil/strings.cc
@@ -8,7 +8,8 @@ namespace nix {
 std::vector<char *> stringsToCharPtrs(const Strings & ss)
 {
     std::vector<char *> res;
-    for (auto & s : ss) res.push_back((char *) s.c_str());
+    // This is const cast since this exists for OS APIs that want char *
+    for (auto & s : ss) res.push_back(const_cast<char *>(s.data()));
     res.push_back(0);
     return res;
 }