diff --git a/src/matcher.c b/src/matcher.c
index 4e7ed3b..bfa7a87 100644
--- a/src/matcher.c
+++ b/src/matcher.c
@@ -24,6 +24,8 @@ apfl_matcher_new(struct gc *gc, struct matcher_instruction_list *milist)
 {
     struct matcher matcher = {
         .instructions = milist,
+        .value_count = 0,
+        .capture_count = 0,
         .values = NULL,
         .captures = NULL,
         .result = false,
@@ -32,10 +34,12 @@ apfl_matcher_new(struct gc *gc, struct matcher_instruction_list *milist)
     if (!init_values_list(gc->allocator, &matcher.values, milist->value_count)) {
         goto error;
     }
+    matcher.value_count = milist->value_count;
 
     if (!init_values_list(gc->allocator, &matcher.captures, milist->capture_count)) {
         goto error;
     }
+    matcher.capture_count = milist->capture_count;
 
     struct matcher *gc_matcher = apfl_gc_new_matcher(gc);
     if (gc_matcher == NULL) {
@@ -54,8 +58,8 @@ error:
 void
 apfl_matcher_deinit(struct apfl_allocator allocator, struct matcher *matcher)
 {
-    FREE_LIST(allocator, matcher->values, matcher->instructions->value_count);
-    FREE_LIST(allocator, matcher->captures, matcher->instructions->capture_count);
+    FREE_LIST(allocator, matcher->values, matcher->value_count);
+    FREE_LIST(allocator, matcher->captures, matcher->capture_count);
 }
 
 void
diff --git a/src/matcher.h b/src/matcher.h
index fbe5cfa..36dbb93 100644
--- a/src/matcher.h
+++ b/src/matcher.h
@@ -11,6 +11,8 @@ extern "C" {
 
 struct matcher {
     struct matcher_instruction_list *instructions;
+    size_t value_count;
+    size_t capture_count;
     struct apfl_value *values;
     struct apfl_value *captures;
     bool result;