https://issues.dlang.org/show_bug.cgi?id=13727

          Issue ID: 13727
           Summary: std.stdio.File not thread-safe
           Product: D
           Version: D2
          Hardware: x86
                OS: Windows
            Status: NEW
          Severity: major
          Priority: P1
         Component: Phobos
          Assignee: nobody@puremagic.com
          Reporter: thecybershadow@gmail.com

////////////// test.d //////////////
import std.array;
import std.parallelism;
import std.stdio;

void main()
{
    foreach (fn;
        ["test.d"]
        .replicate(1000)
        .parallel
    )
    {
        // synchronized
        { File f = File(fn, "rb"); }
    }
}
////////////////////////////////////

On Windows 32-bit, this program will either deadlock, or print a dozen exceptions such as:

std.exception.ErrnoException@std\stdio.d(640): Could not close file `test.d'
(No error)

Uncommenting the "synchronized" line, or commenting the ".parallel" line fixes the problem.

Works fine on 64 bits (with MSVC runtime).

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