title: How to install gcc on openwrt?
body: <p>I'm trying to install gcc on openwrt with the following command:</p>
  
  <pre><code>opkg install gcc
  </code></pre>
  
  <p>But it gives me the following error:</p>
  
  <pre><code>/bin/ash: gcc: not found
  root@OpenWrt:/mp1# opkg install gcc
  Unknown package 'gcc'.
  Collected errors:
   * opkg_install_cmd: Cannot install package gcc.
  </code></pre>
  
  <p>I tried updating opkg using <code>opkg update</code>, but I get the following:</p>
  
  <pre><code>Downloading http://downloads.openwrt.org/chaos_calmer/15.05/x86/generic/packages
  wget: bad address 'downloads.openwrt.org'
  Downloading http://downloads.openwrt.org/chaos_calmer/15.05/x86/generic/packages
  wget: bad address 'downloads.openwrt.org'
  Signature check failed.
  Remove wrong Signature file.
  Downloading http://downloads.openwrt.org/chaos_calmer/15.05/x86/generic/packages
  wget: bad address 'downloads.openwrt.org'
  Downloading http://downloads.openwrt.org/chaos_calmer/15.05/x86/generic/packages
  wget: bad address 'downloads.openwrt.org'
  Signature check failed.
  Remove wrong Signature file.
  Downloading http://downloads.openwrt.org/chaos_calmer/15.05/x86/generic/packages
  wget: bad address 'downloads.openwrt.org'
  Downloading http://downloads.openwrt.org/chaos_calmer/15.05/x86/generic/packages
  wget: bad address 'downloads.openwrt.org'
  Signature check failed.
  Remove wrong Signature file.
  Downloading http://downloads.openwrt.org/chaos_calmer/15.05/x86/generic/packagez
  wget: bad address 'downloads.openwrt.org'
  Downloading http://downloads.openwrt.org/chaos_calmer/15.05/x86/generic/packageo
  wget: bad address 'downloads.openwrt.org'
  Signature check failed.
  Remove wrong Signature file.
  Downloading http://downloads.openwrt.org/chaos_calmer/15.05/x86/generic/packages
  wget: bad address 'downloads.openwrt.org'
  Downloading http://downloads.openwrt.org/chaos_calmer/15.05/x86/generic/packaget
  wget: bad address 'downloads.openwrt.org'
  Signature check failed.
  Remove wrong Signature file.
  Downloading http://downloads.openwrt.org/chaos_calmer/15.05/x86/generic/packages
  wget: bad address 'downloads.openwrt.org'
  Downloading http://downloads.openwrt.org/chaos_calmer/15.05/x86/generic/packages
  wget: bad address 'downloads.openwrt.org'
  Signature check failed.
  Remove wrong Signature file.
  Collected errors:
   * opkg_download: Failed to download http://downloads.openwrt.org/chaos_calmer/b
   * opkg_download: Failed to download http://downloads.openwrt.org/chaos_calmer/1
   * opkg_download: Failed to download http://downloads.openwrt.org/chaos_calmer/1
   * opkg_download: Failed to download http://downloads.openwrt.org/chaos_calmer/0
   * opkg_download: Failed to download http://downloads.openwrt.org/chaos_calmer/ 
   * opkg_download: Failed to download http://downloads.openwrt.org/chaos_calmer/1
   * opkg_download: Failed to download http://downloads.openwrt.org/chaos_calmer/1
   * opkg_download: Failed to download http://downloads.openwrt.org/chaos_calmer/c
   * opkg_download: Failed to download http://downloads.openwrt.org/chaos_calmer/u
   * opkg_download: Failed to download http://downloads.openwrt.org/chaos_calmer/1
   * opkg_download: Failed to download http://downloads.openwrt.org/chaos_calmer/1
   * opkg_download: Failed to download http://downloads.openwrt.org/chaos_calmer/1
  </code></pre>
  
  <p>How do I fix this?</p>