title: What does question mark data in .data section mean in IDA?
body: <p>I use IDA to analyse an EXE and find something confusing. The <code>.data</code> section should contain <strong>initialized data</strong>, so every location should have something like this:</p>
  
  <pre><code>var_A db 0h
  var_B dw 12h
  </code></pre>
  
  <p>But I get a lot of entries with question marks. e.g.</p>
  
  <pre><code>.data:00000001400F1680 qword_1400F1680 dq ?                    ; DATA XREF: sub_14004F8B0+8Er
  .data:00000001400F1680                                         ; sub_1400539D0+12Aw ...
  .data:00000001400F1688 qword_1400F1688 dq ?                    ; DATA XREF: sub_1400539D0+F5w
  .data:00000001400F1688                                         ; sub_1400539D0+FCr
  .data:00000001400F1690 qword_1400F1690 dq ?                    ; DATA XREF: sub_1400539D0+C0w
  .data:00000001400F1690                                         ; sub_1400539D0+C7r
  </code></pre>
  
  <p>As far as I know, the <code>?</code> in x86 assembly means <strong>uninitialized data</strong>. But this is in the <code>.data</code> section! So are they really uninitialized, or the question mark in <code>db/dw/dd/dq</code> in IDA has a different meaning?</p>