https://issues.dlang.org/show_bug.cgi?id=20723

          Issue ID: 20723
           Summary: std.random.unpredictableSeed: on x86/x86-64 try using
                    RDSEED when there is no arc4random
           Product: D
           Version: D2
          Hardware: x86_64
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: n8sh.secondary@hotmail.com

In the past an obstacle to this enhancement was that it would only work with DMD, but LDC version 1.20.0 added support for data directives in DMD-style inline asm.

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