diff --git a/src/util/string.h b/src/util/string.h
index 76f2f403f..4d8bc72c4 100644
--- a/src/util/string.h
+++ b/src/util/string.h
@@ -182,6 +182,7 @@ struct string {
  * @returns @a string if successful, or NULL if out of memory.
  * @post done_string(@a string) is safe, even if this returned NULL.
  * @relates string */
+#ifdef _cplusplus
 #ifdef DEBUG_MEMLEAK
 [[nodiscard]] struct string *init_string__(const char *file, int line, struct string *string);
 #define init_string(string) init_string__(__FILE__, __LINE__, string)
@@ -189,6 +190,16 @@ struct string {
 [[nodiscard]] struct string *init_string(struct string *string);
 #endif
 
+#else
+
+#ifdef DEBUG_MEMLEAK
+struct string *init_string__(const char *file, int line, struct string *string);
+#define init_string(string) init_string__(__FILE__, __LINE__, string)
+#else
+struct string *init_string(struct string *string);
+#endif
+
+#endif
 /** Resets @a string and free()s the string.source member.
  * @relates string */
 void done_string(struct string *string);