diff --git a/src/rvprof_internal.h b/src/rvprof_internal.h
index aa6234d..e7c42e0 100644
--- a/src/rvprof_internal.h
+++ b/src/rvprof_internal.h
@@ -71,6 +71,12 @@ typedef struct {
     double inclusive_percent;
 } function_stats_t;
 
+// stack info
+typedef struct {
+    char* stack_path;
+    int stid;
+} stack_info_t;
+
 // dynamic array structure (could switch to a more sophisticated container + template if we would move to C++ at some point)
 #define DECLARE_DYNAMIC_ARRAY(type, name) \
 typedef struct { \
@@ -82,6 +88,7 @@ typedef struct { \
 DECLARE_DYNAMIC_ARRAY(region_t, region);
 DECLARE_DYNAMIC_ARRAY(function_stats_t, function_stats);
 DECLARE_DYNAMIC_ARRAY(symbol_entry_t, symbol);
+DECLARE_DYNAMIC_ARRAY(stack_info_t, stack_info);
 
 #ifdef __cplusplus
 }