From 5984bc520478d6f51fab79de3477fb690ab74ccd Mon Sep 17 00:00:00 2001
From: "Timur A. Fatkhullin" <timur@sao.ru>
Date: Fri, 5 Jun 2026 09:44:30 +0300
Subject: [PATCH] mcc_keyvalue.h: add fix to prevent GCC compilation crashing

---
 include/mcc/mcc_keyvalue.h | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/include/mcc/mcc_keyvalue.h b/include/mcc/mcc_keyvalue.h
index aa5384c..7e765a2 100644
--- a/include/mcc/mcc_keyvalue.h
+++ b/include/mcc/mcc_keyvalue.h
@@ -411,16 +411,38 @@ public:
 
         std::error_code ec{};
 
+#ifdef __GNUG__
+// to fix GCC compilation crash for the versions < 16
+#if GCC_VERSION < 160000
+        auto write_rec = [&output_buffer, &rec_delim, &ec, obj_ptr = this]<size_t I = 0>(this auto& self) -> void {
+#else
         auto write_rec = [&output_buffer, &rec_delim, &ec, this]<size_t I = 0>(this auto& self) -> void {
+#endif
+#endif
             if constexpr (I < NUMBER_OF_RECORDS) {
                 if constexpr (OPOLICY == MccKeyValueHolder::OPOLICY_CHANGED_ONLY) {
+#ifdef __GNUG__
+// to fix GCC compilation crash for the versions < 16
+#if GCC_VERSION < 160000
+                    if (obj_ptr->_changedKey.count(obj_ptr->_hashes[I]) == 0) {
+#else
                     if (_changedKey.count(_hashes[I]) == 0) {
+#endif
+#endif
                         self.template operator()<I + 1>();
                         return;
                     }
                 }
 
                 ec = formatRecord<I>(output_buffer, rec_delim);
+#ifdef __GNUG__
+// to fix GCC compilation crash for the versions < 16
+#if GCC_VERSION < 160000
+                ec = obj_ptr->template formatRecord<I>(output_buffer, rec_delim);
+#else
+                ec = formatRecord<I>(output_buffer, rec_delim);
+#endif
+#endif
                 if (ec) {
                     return;
                 }