Index: aocutils.c
==================================================================
--- aocutils.c
+++ aocutils.c
@@ -39,11 +39,11 @@
     size_t s = 512;
     size_t r = 0;
     while ((ch = fgetc(h)) != EOF) {
         if (r == s) {
             //grow tmp
-            char *ttmp = realloc(tmp, (13*s)/8);
+            char *ttmp = realloc(tmp, (13*s)/8); // 13/8 is within 0.5% of the golden ratio
             if (ttmp) {
                 tmp = ttmp;
                 s = (13*s)/8;
             } else {
                 free(tmp);