1 files changed, 3 insertions, 0 deletions
diff --git a/src/path.h b/src/path.h
index 1e40061..ed9591b 100644
--- a/src/path.h
+++ b/src/path.h
@@ -2,6 +2,7 @@
 #define PATH_H
 
 #include <gsl/gsl_spline.h>
+#include <stddef.h> /* for size_t */
 
 /* Minimum value for the scattering RMS `theta0`.
  *
@@ -20,6 +21,8 @@ typedef struct path {
     double dir[3];
     double theta0;
 
+    size_t n;
+
     double *s;
     double *x;
     double *y;