title: why is warning for variable being uninitialized supressed when kernel is compiled with size optimization config enabled?
body: <p>trying to optimize kernel boot time, I disabled the <code>CONFIG_CC_OPTIMIZE_FOR_SIZE</code> flag in config. This resulted in a lot of <code>may-be uninitialized</code> warning (which was treated as error). </p>
  
  <p>Trying to debug that I found that in Makefile:</p>
  
  <pre><code>ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
  KBUILD_CFLAGS   += -Os $(call cc-disable-warning,maybe-uninitialized,)
  else
  KBUILD_CFLAGS   += -O2
  endif
  </code></pre>
  
  <p>I dont understand the reson behind disabling the warning for uninitialized variable when kernel is size optimized and not other wise. What is the thought behind this and if i add flag to ignore the uninitialized variables in the later case of "not optimized for size", what issues I can face if any.</p>
  
  <p>Any help is appreciated.</p>
  
  <p>Thank you</p>