mdbx: workaround MSVC C11-atomics and fix spilling internal accounting for MDBX_AVOID_MSYNC=ON.

2026-08-05 mdbx: update ChangeLog.
2026-08-05 mdbx: add comments and rename internal `sanitizer_probe_page_dangling()`.
2026-08-05 mdbx-cmake: use `CXX,C` for target-options as workaround cmake/visual-studio bugs.
2026-08-05 mdbx: fix copy&pase bugs in `sanitizer_kind_of_poison()` and `sanitizer_probe_page()`.
2026-08-05 mdbx-cmake: remove extra `/Oy` "omit frame pointers".
2026-08-05 mdbx-cmake: remove redundant `/utf-8`.
2026-08-05 mdbx-msvc: add compile-time guard for C11 atomics.
2026-08-05 mdbx-cmake: add `/experimental:c11atomics` for bad MSVC compiler to enable C11 atomics.
2026-08-05 mdbx-msvc: fixed MSVC warnings of implicit narrow-casting.
2026-08-05 mdbx-cmake: minor refine show compiler options.
2026-08-05 mdbx: fix copy&paste mistake in `key2float()`.
2026-08-04 mdbx: introduce `page_tmp_txnid_signature()` for clarity, checking and debugging.
2026-08-04 mdbx: push source page to the cursor's stash while splitting.
2026-08-04 mdbx: fix spilling/accounting for `MDBX_AVOID_MSYNC=ON`.
2026-08-03 mdbx: tracing of tmp-pages during splitting to avoid false-positive "dangling" issues.
2026-08-03 mdbx-tests: alter make-targets inside `stochastic` script.
2026-08-03 mdbx: drop minor unnecessary `if()` guard in `cursor_del()`.
2026-08-03 mdbx: refine/relax `txn_probe_dbi_cursors_stacks()`.
2026-08-03 mdbx-doc: minor clarify internal comments.

Author: erthink

CMakeLists.txt

@@ -732,10 +732,6 @@ else()
   message(STATUS "Use C${MDBX_C_STANDARD} for libmdbx but C++ portion is disabled")
 endif()
 
-if(MSVC)
-  add_compile_options("$<$<COMPILE_LANGUAGE:CXX,C>:/utf-8>")
-endif()
-
 if(WIN32 AND CMAKE_SYSTEM_ARCH STREQUAL "x86" AND NOT MDBX_NATIVE_SEH)
   enable_language(ASM_MASM)
   add_library(mdbx_safeseh OBJECT "${MDBX_SOURCE_DIR}/windows-safeseh.asm")
@@ -754,7 +750,7 @@ macro(target_setup_options TARGET)
       set_target_properties(${TARGET} PROPERTIES CXX_STANDARD ${MDBX_CXX_STANDARD} CXX_STANDARD_REQUIRED ON)
     endif()
     if(MSVC AND NOT MSVC_VERSION LESS 1910)
-      target_compile_options(${TARGET} INTERFACE "/Zc:__cplusplus")
+      target_compile_options(${TARGET} INTERFACE "$<$<COMPILE_LANGUAGE:CXX>:/Zc:__cplusplus>")
     endif()
   endif()
   if(CC_HAS_FASTMATH AND NOT (CMAKE_COMPILER_IS_CLANG AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 10))
@@ -767,15 +763,15 @@ macro(target_setup_options TARGET)
     target_compile_options(${TARGET} PRIVATE "-march=native")
   endif()
   if(MSVC)
+    if(MSVC_C11_MAD_ATOMICS)
+      target_compile_options(${TARGET} PRIVATE "$<$<COMPILE_LANGUAGE:CXX,C>:/experimental:c11atomics>")
+    endif()
     if(MDBX_WITHOUT_MSVC_CRT)
       target_compile_options(${TARGET} PRIVATE "$<$<COMPILE_LANGUAGE:CXX,C>:/fp:fast;/fp:except-;/GS-;/Gs->")
     endif()
     if(CC_HAS_FORCE_INTERLOCKED_CALL)
       target_compile_options(${TARGET} PRIVATE "$<$<COMPILE_LANGUAGE:CXX,C>:$<$<CONFIG:Release>:/forceInterlockedFunctions->>")
     endif()
-    if(CC_HAS_Oy_Omit_Frame_Pointers)
-      target_compile_options(${TARGET} PRIVATE "$<$<COMPILE_LANGUAGE:CXX,C>:$<$<CONFIG:Release>:/Oy>>")
-    endif()
   endif()
 endmacro()
 
@@ -1048,7 +1044,7 @@ if(NOT DEFINED MDBX_BUILD_TIMESTAMP)
 endif()
 set(MDBX_BUILD_FLAGS ${CMAKE_C_FLAGS})
 if(MDBX_BUILD_CXX)
-  set(MDBX_BUILD_FLAGS ${CMAKE_CXX_FLAGS})
+  list(APPEND MDBX_BUILD_FLAGS ${CMAKE_CXX_FLAGS})
 endif()
 
 # append cmake's build-type flags and defines
@@ -1072,12 +1068,17 @@ if(defs_list)
   list(APPEND MDBX_BUILD_FLAGS ${defs_list})
 endif()
 
-# get target compile options
+# get target compile options & flags
 get_target_property(options_list ${target4fetch} COMPILE_OPTIONS)
 if(options_list)
   list(APPEND MDBX_BUILD_FLAGS ${options_list})
 endif()
+get_target_property(options_list ${target4fetch} COMPILE_FLAGS)
+if(options_list)
+  list(APPEND MDBX_BUILD_FLAGS ${options_list})
+endif()
 
+separate_arguments(MDBX_BUILD_FLAGS)
 list(REMOVE_DUPLICATES MDBX_BUILD_FLAGS)
 string(REPLACE ";" " " MDBX_BUILD_FLAGS "${MDBX_BUILD_FLAGS}")
 if(CMAKE_CONFIGURATION_TYPES)

ChangeLog.md

@@ -83,6 +83,8 @@ The supporting release of a stable branch with bug fixes.
 
  - On Windows provided `mdbx_env_deleteA()` and define `mdbx_env_deleteT()` depend on the `UNICODE`.
 
+ - Added `/experimental:c11atomics` workaround for MSVC compiler weakness to enable C11 atomics.
+
 ### Fixes:
 
  - Fixed the [issue](https://github.com/Mithril-mine/libmdbx/issues/361) of losing a table content after abortion the nested transaction where such table was dropped.
@@ -122,6 +124,7 @@ The supporting release of a stable branch with bug fixes.
     - Introduced the internal `TXN_NIPPED` flag to suspend spilling during GC processing.
     - Fixed tracking and invalidation of the inner part of the sibling cursors.
     - Reworked cursor's stack with introducing the `stash` of pages.
+    - Fixed spilling/accounting for `MDBX_AVOID_MSYNC=ON`.
 
  - C++ API:
     - Fixed ODR violations warnings from modern GCC while both LTO and UBSAN are enabled.
@@ -146,6 +149,8 @@ The supporting release of a stable branch with bug fixes.
     - Fixed running `ctest -T memcheck` by adding workaround of CTest/CMake bugs for Valgrind parameters.
     - Fixed/removed leftover usage of float point in `mdbx_stat` utility.
     - Fixed `mdbx_defrag` for `-f` option handling.
+    - Fixed MSVC warnings of implicit narrow type-casting.
+    - Added compile-time guard for C11 atomics to avoid wrong code generation on non-x86 platforms by MSVC.
     - etc...
 
 --------------------------------------------------------------------------------

VERSION.json

@@ -1 +1 @@
-{ "git_describe": "v0.14.2-508-g9abf372f", "git_timestamp": "2026-08-03T15:34:28+03:00", "git_tree": "2c8fe36d9bdae185c8ee58be29afa4e2bc95b819", "git_commit": "9abf372f37ff8168ec41a900a71e041b345497b4", "semver": "0.14.2.508" }
+{ "git_describe": "v0.14.2-527-g6c0d0e15", "git_timestamp": "2026-08-05T17:32:59+03:00", "git_tree": "d11f6d7a1469db91ff8720f9c65ab9fc98314d6c", "git_commit": "6c0d0e15fa37d68b269a212f58bb581403afe421", "semver": "0.14.2.527" }

cmake/compiler.cmake

@@ -354,7 +354,6 @@ endif()
 
 if(MSVC)
   check_compiler_flag("/WX" CC_HAS_WERROR)
-  check_compiler_flag("/Oy" CC_HAS_Oy_Omit_Frame_Pointers)
   check_compiler_flag("/fsanitize=address" CC_HAS_ASAN)
   check_compiler_flag("/fsanitize=undefined" CC_HAS_UBSAN)
   check_compiler_flag("/forceInterlockedFunctions" CC_HAS_FORCE_INTERLOCKED_CALL)
@@ -433,6 +432,9 @@ if(CMAKE_C_COMPILER_LOADED)
       endif()
     endif()
   endif()
+  if(MSVC)
+    check_c_compiler_flag("/experimental:c11atomics" MSVC_C11_MAD_ATOMICS)
+  endif()
 endif()
 
 # Check for LTO support by GCC

config.h.in

@@ -1,4 +1,4 @@
-/* This file is part of the libmdbx amalgamated source code (v0.14.2-508-g9abf372f at 2026-08-03T15:34:28+03:00),
+/* This file is part of the libmdbx amalgamated source code (v0.14.2-527-g6c0d0e15 at 2026-08-05T17:32:59+03:00),
  * it is the template for libmdbx's config.h
  ******************************************************************************/
 

mdbx-internals.h

@@ -1,4 +1,4 @@
-/* This file is part of the libmdbx amalgamated source code (v0.14.2-508-g9abf372f at 2026-08-03T15:34:28+03:00).
+/* This file is part of the libmdbx amalgamated source code (v0.14.2-527-g6c0d0e15 at 2026-08-05T17:32:59+03:00).
  *
  * libmdbx (aka MDBX) is an extremely fast, compact, powerful, embeddedable, transactional key-value storage engine with
  * open-source code. MDBX has a specific set of properties and capabilities, focused on creating unique lightweight
@@ -24,7 +24,7 @@
 
 #define xMDBX_ALLOY 1  /* alloyed build */
 
-#define MDBX_BUILD_SOURCERY bec3014f96f0c34a9c4c81b6950507a931e4251a04ad756d0ee866f57f9360d8_v0_14_2_508_g9abf372f
+#define MDBX_BUILD_SOURCERY d08dda1c90a1febd510b99380a13919a304eaca3bfe9bd1025bd706109f2a8f0_v0_14_2_527_g6c0d0e15
 
 #define LIBMDBX_INTERNALS
 #define MDBX_DEPRECATED
@@ -3439,12 +3439,12 @@ MDBX_MAYBE_UNUSED static inline int log_if_error(const int err, const char *func
 /* --------------------------------------------------------------------------------------------------------------- */
 
 MDBX_MAYBE_UNUSED static inline char sanitizer_kind_of_poison(const void *addr, size_t size) {
-  if (ASAN_REGISON_IS_POISONED(addr, sizeof(size)))
+  if (ASAN_REGISON_IS_POISONED(addr, size))
     return 'P';
   if (mdbx_running_on_Valgrind()) {
-    if (!VALGRIND_CHECK_MEM_IS_ADDRESSABLE(addr, sizeof(size)))
+    if (VALGRIND_CHECK_MEM_IS_ADDRESSABLE(addr, size))
       return 'N';
-    if (!VALGRIND_CHECK_MEM_IS_DEFINED(addr, sizeof(size)))
+    if (VALGRIND_CHECK_MEM_IS_DEFINED(addr, size))
       return 'U';
   }
   return 0;