From 74d5a42578c2b9777a06eea9aa9f870713e11846 Mon Sep 17 00:00:00 2001
From: sasgas <sasgas@castis.com>
Date: Tue, 9 Nov 2021 11:29:01 +0900
Subject: [PATCH] mdbx: fix compilation with devtoolset-9 on CentOS/RHEL 7.

devtoolset is always using the old ABI
https://bugzilla.redhat.com/show_bug.cgi?id=1546704
https://stackoverflow.com/questions/49393888/how-can-i-use-the-new-c-11-abi-with-devtoolset-7-on-centos-rhel
---
 mdbx.h++     | 3 ++-
 src/mdbx.c++ | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/mdbx.h++ b/mdbx.h++
index 8390dcfa..d47906ee 100644
--- a/mdbx.h++
+++ b/mdbx.h++
@@ -286,7 +286,8 @@ class cursor;
 class cursor_managed;
 
 #if defined(DOXYGEN) ||                                                        \
-    defined(__cpp_lib_memory_resource) && __cpp_lib_memory_resource >= 201603L
+    (defined(__cpp_lib_memory_resource) &&                                     \
+     __cpp_lib_memory_resource >= 201603L && _GLIBCXX_USE_CXX11_ABI)
 /// \brief Default polymorphic allocator for modern code.
 using polymorphic_allocator = ::std::pmr::string::allocator_type;
 #endif /* __cpp_lib_memory_resource >= 201603L */
diff --git a/src/mdbx.c++ b/src/mdbx.c++
index a6db48ff..e1e89942 100644
--- a/src/mdbx.c++
+++ b/src/mdbx.c++
@@ -992,7 +992,8 @@ bool from_base64::is_erroneous() const noexcept {
 
 template class LIBMDBX_API_TYPE buffer<legacy_allocator>;
 
-#if defined(__cpp_lib_memory_resource) && __cpp_lib_memory_resource >= 201603L
+#if defined(__cpp_lib_memory_resource) &&                                      \
+    __cpp_lib_memory_resource >= 201603L && _GLIBCXX_USE_CXX11_ABI
 template class LIBMDBX_API_TYPE buffer<polymorphic_allocator>;
 #endif /* __cpp_lib_memory_resource >= 201603L */