diff --git a/Makefile b/Makefile
index dd37997..eabbc68 100644
--- a/Makefile
+++ b/Makefile
@@ -10,7 +10,7 @@ CFLAGS := -g -fPIC -O3 -fno-builtin \
 		-Wall -Werror -Wno-nonnull -Wno-nonnull-compare -Wno-unused-function -Wno-array-bounds -Wno-stringop-overflow
 
 # to enable log
-# -DCKB_C_STDLIB_PRINTF -DCKB_C_STDLIB_PRINTF_BUFFER_SIZE=1024
+CFLAGS += -DCKB_C_STDLIB_PRINTF -DCKB_C_STDLIB_PRINTF_BUFFER_SIZE=1024
 
 LDFLAGS := -nostdlib -nostartfiles -Wl,-static -Wl,--gc-sections
 
diff --git a/c/ckb_identity.h b/c/ckb_identity.h
index daef488..38dfc0e 100644
--- a/c/ckb_identity.h
+++ b/c/ckb_identity.h
@@ -676,6 +676,7 @@ int convert_tron_message(const uint8_t *msg, size_t msg_len, uint8_t *new_msg,
 }
 
 bool is_lock_script_hash_present(uint8_t *lock_script_hash) {
+  printf("is_lock_script_hash_present");
   int err = 0;
   size_t i = 0;
   while (true) {
@@ -691,10 +692,12 @@ bool is_lock_script_hash_present(uint8_t *lock_script_hash) {
     }
 
     if (memcmp(lock_script_hash, buff, BLAKE160_SIZE) == 0) {
+      printf("owner lock found");
       return true;
     }
     i += 1;
   }
+  printf("owner lock not found");
   return false;
 }