https://issues.dlang.org/show_bug.cgi?id=22051

          Issue ID: 22051
           Summary: compiler allows compilation of malformed writefln
                    statement, causing run-time crashes
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: james.p.leblanc@gmail.com

// this compiles (but notice the naked percent sign), causing run-time crash

import std.stdio;

void main (){
   bool myvar = true;
   writefln("Bool: %: ", myvar);
}

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