$ chicken-install -s blas
fetching blas
fetching bind
fetching silex
fetching coops
fetching record-variants
building silex
   /usr/bin/csc -host -D compiling-extension -J -s -regenerate-import-libraries -setup-mode -I /home/jeremy/.cache/chicken-install/silex -C -I/home/jeremy/.cache/chicken-install/silex -O2 -d1 silex.scm -o /home/jeremy/.cache/chicken-install/silex/silex.so

Warning: Invalid argument
  In file `silex.scm:472',
  In module `silex',
  In procedure `digraph',
  In procedure `store-final339',
  In procedure `loop',
  In procedure call:

    (scheme#vector-set! prio voisin infinity)

  Argument #2 to procedure `vector-set!' has an invalid type:

    false

  The expected type is:

    fixnum

  This is the expression:

    voisin

  Procedure `vector-set!' from module `scheme' has this type:

    (vector fixnum * -> undefined)
   /usr/bin/csc -regenerate-import-libraries -M -setup-mode -static -I /home/jeremy/.cache/chicken-install/silex -emit-link-file /home/jeremy/.cache/chicken-install/silex/silex.link -host -D compiling-extension -c -unit silex -D compiling-static-extension -C -I/home/jeremy/.cache/chicken-install/silex -O2 -d1 silex.scm -o /home/jeremy/.cache/chicken-install/silex/silex.static.o

Warning: Invalid argument
  In file `silex.scm:472',
  In module `silex',
  In procedure `digraph',
  In procedure `store-final339',
  In procedure `loop',
  In procedure call:

    (scheme#vector-set! prio voisin infinity)

  Argument #2 to procedure `vector-set!' has an invalid type:

    false

  The expected type is:

    fixnum

  This is the expression:

    voisin

  Procedure `vector-set!' from module `scheme' has this type:

    (vector fixnum * -> undefined)
   /usr/bin/csc -setup-mode -s -host -I /home/jeremy/.cache/chicken-install/silex -C -I/home/jeremy/.cache/chicken-install/silex -O2 -d0 silex.import.scm -o /home/jeremy/.cache/chicken-install/silex/silex.import.so
installing silex