title: ld: library not found for -lbundle1.o even though xcode command line tools are installed
body: <p>When installing a program using gfortran i get the error </p>
  
  <pre><code>ld: library not found for -lbundle1.o
  collect2: error: ld returned 1 exit status
  </code></pre>
  
  <p>Searching stackoverflow i found <a href="https://stackoverflow.com/questions/19868897/library-not-found-for-lbundle1-o-when-installing-python-packages-ffnet-spacep">library not found for -lbundle1.o when installing python packages (ffnet, spacepy) on my mac</a> , where the answer is to call </p>
  
  <pre><code>xcode-select --install
  </code></pre>
  
  <p>To install the xcode command line tools. This then gave me</p>
  
  <pre><code>xcode-select: error: command line tools are already installed, use "Software Update" to install updates
  </code></pre>
  
  <p>Telling me that i have already installed them. In case my installation was somehow corrupted i have already tried deleting /Library/Developer/CommandLineTools and reinstalling but it did not change anything. (My macOS version is 10.14.1, xcode-select version 2354)</p>