Address clang-tidy error.
Address clang-tidy error.

cellml/libcellml,hsorby/libcellml,hsorby/libcellml,hsorby/libcellml,nickerso/libcellml,hsorby/libcellml,nickerso/libcellml,nickerso/libcellml,cellml/libcellml,cellml/libcellml,nickerso/libcellml,cellml/libcellml