February 10, 2019
https://issues.dlang.org/show_bug.cgi?id=19664

          Issue ID: 19664
           Summary: All tools should be built for 64 bit
           Product: D
           Version: D2
          Hardware: x86_64
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: tools
          Assignee: nobody@puremagic.com
          Reporter: doob@me.com

All tools shipped with a DMD release should be built for the same architecture. For a 64 bit release, the following tools are built for 32 bit: "dumpobj", "obj2asm" and "shell". This is extra important for macOS since Mojave is the last release where 32 bit applications will work and with DMD 2.085.0 we have deprecated the support for 32 bit on macOS.

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