• via Digitalmars-d-bugs (32/32) Jul 12 2014 https://issues.dlang.org/show_bug.cgi?id=13111

via Digitalmars-d-bugs <digitalmars-d-bugs puremagic.com> writes:

https://issues.dlang.org/show_bug.cgi?id=13111

          Issue ID: 13111
           Summary: GC.realloc returns invalid memory for large
                    reallocation
           Product: D
           Version: unspecified
          Hardware: x86_64
                OS: Windows
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: druntime
          Assignee: nobody puremagic.com
          Reporter: r.sagitario gmx.de

Reported by Gary Willoughby, reduced by anonymous:

import core.memory;
void main()
{
     alias T = ubyte;

     enum size1 = 2_049; /* > 2_048 = 2^^11 */
     enum size2 = 1_048_577; /* > 1_048_576 = 2^^20 */

     T* _data;
     _data = cast(T*)GC.calloc(size1, GC.BlkAttr.NO_MOVE);
     _data = cast(T*)GC.realloc(_data, size2, GC.BlkAttr.NO_MOVE);

     T* _pointer = _data;
     foreach(i; 0 .. size2)
     {
         *_pointer = 0; /* segfault at i = 1_048_576 */
         _pointer++;
     }
}

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