title: Building C++ program with Blas/Lapack libraries
body: <p>I'm struggling to build with Visual Studio 2019 a C++ application that needs BLAS/LAPACK libraries.</p>
  
  <p>When building the problem, link.exe produces these errors:</p>
  
  <pre><code>l1tf.obj : error LNK2001: unresolved external symbol dgbsv_
  l1tf.obj : error LNK2001: unresolved external symbol dpbtrs_
  l1tf.obj : error LNK2001: unresolved external symbol dgbtrf_
  l1tf.obj : error LNK2001: unresolved external symbol dpbtrf_
  ...
  </code></pre>
  
  <p>So, I downloaded the Windows versions of BLAS and LAPACK libraries and added these parameters to the linker:</p>
  
  <blockquote>
    <p>/LIBPATH:D:\my_program\libs
    LAPACK.lib BLAS.lib</p>
  </blockquote>
  
  <p>But I still get the same errors… I investigated the content of LAPACK.lib with dumpbins and the missing symbols (dgbsv, etc) can be found.</p>
  
  <p>What can be the issue?</p>