2 files changed, 2 insertions, 0 deletions
diff --git a/nlsolve.c b/nlsolve.c
index 9366605..f81e701 100644
--- a/nlsolve.c
+++ b/nlsolve.c
@@ -21,6 +21,7 @@
 #include <errno.h>
 #include <limits.h>
 #include <math.h>
+#include <stddef.h>
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
diff --git a/pssolve.c b/pssolve.c
index 906ec00..32a34b1 100644
--- a/pssolve.c
+++ b/pssolve.c
@@ -20,6 +20,7 @@
 #include <inttypes.h>
 #include <limits.h>
 #include <math.h>
+#include <stddef.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>