diff --git a/CMake/AbseilDll.cmake b/CMake/AbseilDll.cmake
index 32cc28f..e51d6df 100644
--- a/CMake/AbseilDll.cmake
+++ b/CMake/AbseilDll.cmake
@@ -699,31 +699,44 @@ set(ABSL_INTERNAL_TEST_DLL_TARGETS
 
 include(CheckCXXSourceCompiles)
 
-check_cxx_source_compiles(
-  [==[
-#ifdef _MSC_VER
-#  if _MSVC_LANG < 201703L
-#    error "The compiler defaults or is configured for C++ < 17"
-#  endif
-#elif __cplusplus < 201703L
-#  error "The compiler defaults or is configured for C++ < 17"
-#endif
-int main() { return 0; }
-]==]
+message(WARNING "ABSL_CXX_STANDARD: ${ABSL_CXX_STANDARD}")
+message(WARNING "CMAKE_CXX_STANDARD: ${CMAKE_CXX_STANDARD}")
+message(WARNING "CMAKE_CXX_STANDARD_REQUIRED: ${CMAKE_CXX_STANDARD_REQUIRED}")
+message(WARNING "CMAKE_CXX_FLAGS: ${CMAKE_CXX_FLAGS}")
+
+if(CMAKE_CXX_STANDARD GREATER_EQUAL 17)
+  set(ABSL_INTERNAL_AT_LEAST_CXX17 TRUE)
+else()
+  check_cxx_source_compiles(
+    [==[
+  #ifdef _MSC_VER
+  #  if _MSVC_LANG < 201703L
+  #    error "The compiler defaults or is configured for C++ < 17"
+  #  endif
+  #elif __cplusplus < 201703L
+  #  error "The compiler defaults or is configured for C++ < 17"
+  #endif
+  int main() { return 0; }
+  ]==]
   ABSL_INTERNAL_AT_LEAST_CXX17)
+endif()
 
-check_cxx_source_compiles(
-  [==[
-#ifdef _MSC_VER
-#  if _MSVC_LANG < 202002L
-#    error "The compiler defaults or is configured for C++ < 20"
-#  endif
-#elif __cplusplus < 202002L
-#  error "The compiler defaults or is configured for C++ < 20"
-#endif
-int main() { return 0; }
-]==]
+if(CMAKE_CXX_STANDARD GREATER_EQUAL 20)
+  set(ABSL_INTERNAL_AT_LEAST_CXX20 TRUE)
+else()
+  check_cxx_source_compiles(
+    [==[
+  #ifdef _MSC_VER
+  #  if _MSVC_LANG < 202002L
+  #    error "The compiler defaults or is configured for C++ < 20"
+  #  endif
+  #elif __cplusplus < 202002L
+  #  error "The compiler defaults or is configured for C++ < 20"
+  #endif
+  int main() { return 0; }
+  ]==]
   ABSL_INTERNAL_AT_LEAST_CXX20)
+endif()
 
 if(ABSL_INTERNAL_AT_LEAST_CXX20)
   set(ABSL_INTERNAL_CXX_STD_FEATURE cxx_std_20)
@@ -731,6 +744,7 @@ elseif(ABSL_INTERNAL_AT_LEAST_CXX17)
   set(ABSL_INTERNAL_CXX_STD_FEATURE cxx_std_17)
 else()
   set(ABSL_INTERNAL_CXX_STD_FEATURE cxx_std_14)
+  message(FATAL_ERROR "Should not pass here !!!")
 endif()
 
 function(absl_internal_dll_contains)
diff --git a/absl/flags/declare.h b/absl/flags/declare.h
index 8d2a856..a154046 100644
--- a/absl/flags/declare.h
+++ b/absl/flags/declare.h
@@ -59,10 +59,15 @@ ABSL_NAMESPACE_END
 
 // Internal implementation of ABSL_DECLARE_FLAG to allow macro expansion of its
 // arguments. Clients must use ABSL_DECLARE_FLAG instead.
+#if defined(_MSC_VER)
+#define ABSL_DECLARE_FLAG_INTERNAL(type, name) \
+  extern absl::Flag<type> FLAGS_##name
+#else
 #define ABSL_DECLARE_FLAG_INTERNAL(type, name)               \
   extern absl::Flag<type> FLAGS_##name;                      \
   namespace absl /* block flags in namespaces */ {}          \
   /* second redeclaration is to allow applying attributes */ \
   extern absl::Flag<type> FLAGS_##name
+#endif  // _MSC_VER
 
 #endif  // ABSL_FLAGS_DECLARE_H_