title: Compiling with gfortran: undefined reference to iargc_
body: <p>I'm using gfortran [GNU Fortran (GCC) 4.8.3 20140911 (Red Hat 4.8.3-7)] on a Fedora 20 x86_64 to compile a bunch of Fortran 77 code which refers to 'iargc' function in the following manner:</p>
  <blockquote>
  <p>bin2D2nc.f:31:    integer iargc,strlen1</p>
  <p>bin2D2nc.f:32:    external iargc,strlen1</p>
  <p>bin2D2nc.f:44:    i=iargc()</p>
  </blockquote>
  <p>When the make script reaches the compilation comand bellow,</p>
  <pre><code>gfortran -O3 -ffixed-line-length-132 -fall-intrinsics -I/home/santiago/Install/netcdf_sam/include   -o bin2D2nc -I./SRC ./SRC/bin2D2nc.f ./SRC/hbuf_lib.f ./SRC/cape.f ./SRC/cin.f -L/home/santiago/Install/netcdf_sam/lib  -lnetcdf -L/usr/lib64 -lpthread
  </code></pre>
  <p>I receive these messages:</p>
  <blockquote>
  <p>bin2D2nc.f:(.text+0x14): undefined reference to `iargc_'</p>
  <p>collect2: error: ld returned 1 exit status</p>
  <p>make: ** [bin2D2nc] Erro 1</p>
  </blockquote>
  <p>I'm not the author of this code. As far as I know, I set up correctly the library paths in the <a href="http://pastebin.com/BgmhqbFb" rel="nofollow noreferrer">makefile</a>.</p>
  <p>I have found that 'iargc' is a routine for backward compability with GNU Fotran 77, but I don't understand it deeply.</p>
  <p>Could someone give some advise to surpass this problem?</p>