diff --git a/src/hvm.c b/src/hvm.c
index f5753f1..9b970ac 100644
--- a/src/hvm.c
+++ b/src/hvm.c
@@ -1955,8 +1955,9 @@ fn PBind* parse_bind_lookup(u32 name, int side, int *skipped) {
 // Count the number of uses of a target variable in a term
 // Variables are identified by tag + level (and ext for BJ mode).
 fn u32 count_uses(Term t, u32 lvl, u8 tgt, u32 ext) {
-  Term *ts = (Term*)malloc(sizeof(Term) * 1024); // not recursive, since this is a desugared term
-  int ts_idx = 0;
+  u32 ts_cap = 1024;
+  Term *ts = (Term*)malloc(sizeof(Term) * ts_cap);
+  u32 ts_idx = 0;
   ts[ts_idx++] = t;
 
   u32 uses = 0;
@@ -1970,6 +1971,10 @@ fn u32 count_uses(Term t, u32 lvl, u8 tgt, u32 ext) {
     u32 ari = term_arity(t);
     for (u32 i = 0; i < ari; i++) {
       u64 loc = vl + i;
+      if (ts_idx == ts_cap) {
+        ts_cap *= 2;
+        ts = (Term*)realloc(ts, sizeof(Term) * ts_cap);
+      }
       ts[ts_idx++] = HEAP[loc];
     }
   }