title: gcc: error: unrecognized command line option ‘-fsanitize-coverage=trace-pc-guard’
body: <p>During build of Firefox (older versions including 56.0, 57.0), I encountered the following error a lot of times:</p>
  
  <pre><code>gcc: error: unrecognized command line option ‘-fsanitize-coverage=trace-pc-guard’; did you mean ‘-fsanitize-coverage=trace-pc’?
  </code></pre>
  
  <p>no matter in an ASAN build or normal debug build.</p>
  
  <p>With normal debug, I used following options:</p>
  
  <pre><code>ac_add_options --disable-jemalloc
  ac_add_options --enable-crashreporter
  ac_add_options --disable-elf-hack
  export MOZ_DEBUG_SYMBOLS=1
  ac_add_options --enable-debug-symbols
  ac_add_options --disable-install-strip
  ac_add_options --disable-strip
  ac_add_options --disable-optimize
  ac_add_options --enable-debug
  ac_add_options --disable-profiling
  ac_add_options --enable-fuzzing
  </code></pre>
  
  <p>My guess is that it has something to do with the option <strong>--enable-fuzzing</strong>, but no idea why and how to fix.</p>
  
  <p>PS: I have g++, gcc version 7.4.0.</p>