https://issues.dlang.org/show_bug.cgi?id=13607

          Issue ID: 13607
           Summary: BigInt math not usable in @safe code
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: Phobos
          Assignee: nobody@puremagic.com
          Reporter: braddr@puremagic.com

module bitintsafe;

import std.bigint;

void main() @safe
{
    BigInt i, j, k;
    i = j + k;
}

$ dmd -c bigintsafe.d
bigintsafe.d(8): Error: safe function 'D main' cannot call system function
'std.bigint.BigInt.opBinary!("+", BigInt).opBinary'

I started looking into this but the rabit hole is fairly deep.  Filing a bug in hopes that someone will take up the charge on this one while I work on others. I don't consider this an enhancement request since @safe and phobos really need to be in the 'just works' state.

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