NUMCL.EXPORTED:MATMUL
  [symbol]

MATMUL names a compiled function:
  Lambda-list: (NUMCL.IMPL::A NUMCL.IMPL::B &OPTIONAL
                NUMCL.IMPL::RESULT)
  Derived type: (FUNCTION (T T &OPTIONAL T)
                 (VALUES (ARRAY * (* *)) &OPTIONAL))
  Documentation:
    Matrix product of two arrays.
  Source file: /home/puchacz/projects5/other-libs/numcl-master-2019.09.14/src/8linear-algebra2.lisp

MATMUL has a compiler-macro:
  Documentation:
    Matrix product of two arrays.
  Source file: /home/puchacz/projects5/other-libs/numcl-master-2019.09.14/src/8linear-algebra2.lisp