[libc++] Remove a bunch of conditionals on _LIBCPP_DEBUG_LEVEL

Instead of providing two different constructors for iterators that
support the debug mode, provide a single constructor but leave the
container parameter unused when the debug mode is not enabled.

This allows simplifying all the call sites to unconditionally pass
the container, which removes a bunch of duplication in the container's
implementation.

Note that this patch does add some complexity to std::span, however
that is only because std::span has the ability to use raw pointers
as iterators instead of __wrap_iter. In retrospect, I believe it was
a mistake to provide that capability, and so it will be removed in a
future patch, along with the complexity added by this patch.

Differential Revision: https://reviews.llvm.org/D126993

1 files changed, 4 insertions, 6 deletions

diff --git a/libcxx/include/__iterator/wrap_iter.h b/libcxx/include/__iterator/wrap_iter.h
index 69e5ee1..a3f42ca7 100644
--- a/libcxx/include/__iterator/wrap_iter.h
+++ b/libcxx/include/__iterator/wrap_iter.h
@@ -135,17 +135,15 @@ public:
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 iterator_type base() const _NOEXCEPT {return __i;}
 
 private:
-#if _LIBCPP_DEBUG_LEVEL == 2
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11
-    explicit __wrap_iter(const void* __p, iterator_type __x) : __i(__x)
+    explicit __wrap_iter(const void* __p, iterator_type __x) _NOEXCEPT : __i(__x)
     {
+        (void)__p;
+#if _LIBCPP_DEBUG_LEVEL == 2
       if (!__libcpp_is_constant_evaluated())
         __get_db()->__insert_ic(this, __p);
-    }
-#else
-    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11
-    explicit __wrap_iter(iterator_type __x) _NOEXCEPT : __i(__x) {}
 #endif
+    }
 
     template <class _Up> friend class __wrap_iter;
     template <class _CharT, class _Traits, class _Alloc> friend class basic_string;