diff --git a/DESCRIPTION b/DESCRIPTION
index a9fedbb..85fea6f 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -22,5 +22,5 @@ Suggests:
     rmarkdown
 URL: https://github.com/bertcarnell/lhs
 BugReports: https://github.com/bertcarnell/lhs/issues
-RoxygenNote: 7.1.1
+RoxygenNote: 7.2.2
 VignetteBuilder: knitr
diff --git a/src/init.c b/src/init.c
index 4b2d531..6b526b1 100644
--- a/src/init.c
+++ b/src/init.c
@@ -11,7 +11,7 @@
 extern SEXP create_galois_field(SEXP);
 extern SEXP create_oalhs(SEXP, SEXP, SEXP, SEXP);
 extern SEXP geneticLHS_cpp(SEXP, SEXP, SEXP, SEXP, SEXP, SEXP, SEXP);
-extern SEXP get_library_versions();
+extern SEXP get_library_versions(void);
 extern SEXP improvedLHS_cpp(SEXP, SEXP, SEXP);
 extern SEXP maximinLHS_cpp(SEXP, SEXP, SEXP);
 extern SEXP oa_to_lhs(SEXP, SEXP, SEXP, SEXP);
diff --git a/src/lhs_r.cpp b/src/lhs_r.cpp
index b1fa940..8d1d0da 100644
--- a/src/lhs_r.cpp
+++ b/src/lhs_r.cpp
@@ -310,7 +310,7 @@ RcppExport SEXP geneticLHS_cpp(SEXP /*int*/ n, SEXP /*int*/ k, SEXP /*int*/ pop,
   END_RCPP
 }
 
-RcppExport SEXP get_library_versions()
+RcppExport SEXP get_library_versions(void)
 {
   BEGIN_RCPP
     Rcpp::CharacterVector rresult = Rcpp::CharacterVector(1);