https://issues.dlang.org/show_bug.cgi?id=16609

          Issue ID: 16609
           Summary: std.experimental.ndslice.slice issues warnings when
                    building Phobos
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: regression
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: bugzilla@digitalmars.com

Pages of these are generated:

std/experimental/ndslice/slice.d(1926): Warning: toHash() must be declared as
extern (D) size_t toHash() const nothrow @safe, not const pure nothrow @nogc
@system uint()

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