title: Cannot find yasm even though I have installed it
body: <p>I got a strange problem. I tried to install x264. When run sudo ./configure --enable-shared, 
  it gave:</p>
  
  <p><strong>Found no assembler
  Minimum version is yasm-0.7.0
  If you really want to compile without asm, configure with --disable-asm.</strong></p>
  
  <p>But I already installed yasm-0.7.0 ,to prove that ,i run yasm --version,it gave:</p>
  
  <p>*<strong><em>yasm 0.7.0.2066
  Compiled on May  8 2012.
  Copyright (c) 2001-2008 Peter Johnson and other Yasm developers.
  Run yasm --license for licensing overview and summary.</em>*</strong></p>
  
  <p>I install yasm to /usr/local/yasm,
  Why can it not find yasm? </p>