diff --git a/src/api/api_log.cpp b/src/api/api_log.cpp
index e740a21c3..55c8cb853 100644
--- a/src/api/api_log.cpp
+++ b/src/api/api_log.cpp
@@ -32,15 +32,15 @@ static mutex g_log_mux;
 #define SCOPED_LOCK() {}
 #endif
 
-extern "C" {
-    void Z3_close_log_unsafe(void) {
-        if (g_z3_log != nullptr) {
-            g_z3_log_enabled = false;
-            dealloc(g_z3_log);
-            g_z3_log = nullptr;
-        }
+static void Z3_close_log_unsafe(void) {
+    if (g_z3_log != nullptr) {
+        g_z3_log_enabled = false;
+        dealloc(g_z3_log);
+        g_z3_log = nullptr;
     }
+}
 
+extern "C" {
     bool Z3_API Z3_open_log(Z3_string filename) {
         bool res = true;