title: #error "SSE2 instruction set not enabled" when including <emmintrin.h>
body: <p>I´m trying to compile some C++ code with cmake and make that uses the include <code>&lt;emmintrin.h&gt;</code> and get the following make error: </p>
  
  <pre><code> #error "SSE2 instruction set not enabled"
  </code></pre>
  
  <p>I have an Intel Celeron Dual Core processor with a Linux (Mint) system (Kernel 3.5). </p>
  
  <p>According to Wikipedia the Celeron Dual Core is capable to execute SSE2 instructions and the sse2 flag is set according to <code>/proc/cpuinfo</code>. But the author of <a href="https://stackoverflow.com/questions/1894446/taking-advantage-of-sse-and-other-cpu-extensions">this question</a> mentions a limited SSE support of the Intel Celeron. </p>
  
  <p>I've already tried to use the SSE compiler options in my <code>CMakeLists.txt</code>:</p>
  
  <pre><code>set(CMAKE_C_FLAGS ${CMAKE_C_FLAGS} "-msse -msse2 -msse3")
  </code></pre>
  
  <p>..but nothing changed. <code>cmake .</code> works fine but <code>make</code> gives the error message above. </p>
  
  <p>Do I have to change the settings in CMakeLists.txt or does the Celeron Dual Core simply not (fully) support SSE2? </p>