• via Digitalmars-d-bugs (30/30) Jul 24 2015 https://issues.dlang.org/show_bug.cgi?id=14823

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

https://issues.dlang.org/show_bug.cgi?id=14823

          Issue ID: 14823
           Summary: pure function returns uninitialized value
           Product: D
           Version: D2
          Hardware: x86
                OS: Mac OS X
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody puremagic.com
          Reporter: jeff thefirst.org

To reproduce, enter and run the following code:

import std.stdio;
pure int getUninitializedValue()
{
  int[1] array = void; // array is uninitialized
  return array[0];
}
void main(string[] args)
{
  writeln(getUninitializedValue());
}

Expected result: Compiler error for a pure function with uninitialized memory.

Actual result: It prints 185734 (or another uninitialized value from the
stack).

Suggested solution: Don't allow accessing uninitialized memory inside a pure
function.

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