diff --git a/cfg/std.cfg b/cfg/std.cfg
index 6c434b8715c..2b18eb682f7 100644
--- a/cfg/std.cfg
+++ b/cfg/std.cfg
@@ -3238,16 +3238,15 @@ The obsolete function 'gets' is called. With 'gets' you'll get a buffer overrun
       <not-uninit/>
     </arg>
   </function>
-  <!-- struct tm *localtime_s(const time_t *restrict time, struct tm *restrict result) -->
-  <function name="localtime_s,std::localtime_s">
-    <returnValue type="struct tm *"/>
+  <!-- struct tm *localtime_s(const time_t *restrict time, struct tm *restrict result)
+       Order of arguments and return type differs between implementations, define a common baseline here. -->
+  <function name="localtime_s">
     <noreturn>false</noreturn>
     <leak-ignore/>
-    <arg nr="1" direction="in">
+    <arg nr="1">
       <not-null/>
-      <not-uninit/>
     </arg>
-    <arg nr="2" direction="out">
+    <arg nr="2">
       <not-null/>
     </arg>
   </function>
diff --git a/cfg/windows.cfg b/cfg/windows.cfg
index b2251900d42..f01000459c7 100644
--- a/cfg/windows.cfg
+++ b/cfg/windows.cfg
@@ -4654,9 +4654,10 @@ HFONT CreateFont(
       <not-uninit/>
     </arg>
   </function>
-  <!-- errno_t _localtime32_s( struct tm* _tm, const __time32_t *time);
+  <!-- errno_t localtime_s( struct tm* const tmDest, time_t const* const sourceTime);
+       errno_t _localtime32_s( struct tm* _tm, const __time32_t *time);
        errno_t _localtime64_s( struct tm* _tm, const __time64_t *time); -->
-  <function name="_localtime32_s,_localtime64_s">
+  <function name="localtime_s,_localtime32_s,_localtime64_s">
     <returnValue type="errno_t"/>
     <noreturn>false</noreturn>
     <leak-ignore/>
diff --git a/test/cfg/std.c b/test/cfg/std.c
index 997f8204f73..1adaf63f7a4 100644
--- a/test/cfg/std.c
+++ b/test/cfg/std.c
@@ -171,26 +171,6 @@ void nullPointer_qsort(void *base, size_t n, size_t size, int (*cmp)(const void
     qsort(base, n, size, qsort_cmpfunc);
 }
 
-// As with all bounds-checked functions, localtime_s is only guaranteed to be available if __STDC_LIB_EXT1__ is defined by the implementation and if the user defines __STDC_WANT_LIB_EXT1__ to the integer constant 1 before including time.h.
-#ifdef __STDC_LIB_EXT1__
-void uninitvar_localtime_s(const time_t *restrict time, struct tm *restrict result)
-{
-    const time_t *restrict Time;
-    // cppcheck-suppress uninitvar
-    (void)localtime_s(Time, result);
-    (void)localtime_s(time, result);
-}
-
-void nullPointer_localtime_s(const time_t *restrict time, struct tm *restrict result)
-{
-    // cppcheck-suppress nullPointer
-    (void)localtime_s(NULL, result);
-    // cppcheck-suppress nullPointer
-    (void)localtime_s(time, NULL);
-    (void)localtime_s(time, result);
-}
-#endif // __STDC_LIB_EXT1__
-
 size_t bufferAccessOutOfBounds_wcsrtombs(char * dest, const wchar_t ** src, size_t len, mbstate_t * ps)
 {
     char buf[42];
diff --git a/test/cfg/std.cpp b/test/cfg/std.cpp
index e4753a09f7c..27a4beada03 100644
--- a/test/cfg/std.cpp
+++ b/test/cfg/std.cpp
@@ -689,38 +689,6 @@ void *bufferAccessOutOfBounds_memchr(void *s, int c, size_t n)
     return std::memchr(s,c,n);
 }
 
-// As with all bounds-checked functions, localtime_s is only guaranteed to be available if __STDC_LIB_EXT1__ is defined by the implementation and if the user defines __STDC_WANT_LIB_EXT1__ to the integer constant 1 before including time.h.
-#ifdef __STDC_LIB_EXT1__
-void uninitvar_localtime_s(const std::time_t *restrict time, struct tm *restrict result)
-{
-    // cppcheck-suppress valueFlowBailoutIncompleteVar
-    const std::time_t *restrict Time;
-    // TODO cppcheck-suppress uninitvar
-    (void)std::localtime_s(Time, result);
-    (void)std::localtime_s(time, result);
-}
-
-void nullPointer_localtime_s(const std::time_t *restrict time, struct tm *restrict result)
-{
-    // cppcheck-suppress nullPointer
-    (void)std::localtime_s(NULL, result);
-    // cppcheck-suppress nullPointer
-    (void)std::localtime_s(time, NULL);
-    (void)std::localtime_s(time, result);
-}
-
-void memleak_localtime_s(const std::time_t *restrict time, struct tm *restrict result) // #9258
-{
-    const time_t t = time(0);
-    const struct tm* const now = new tm();
-    if (localtime_s(now, &t) == 0) {
-        // cppcheck-suppress valueFlowBailoutIncompleteVar
-        std::cout << now->tm_mday << std::endl;
-    }
-    // cppcheck-suppress memleak
-}
-#endif // __STDC_LIB_EXT1__
-
 size_t nullPointer_strftime(char *s, size_t max, const char *fmt, const struct tm *p)
 {
     // cppcheck-suppress nullPointer
diff --git a/test/cfg/windows.cpp b/test/cfg/windows.cpp
index 37c580a0134..9beac7f6a86 100644
--- a/test/cfg/windows.cpp
+++ b/test/cfg/windows.cpp
@@ -1260,3 +1260,31 @@ void constParameterPointer_SetupDiGetDeviceInstanceId(HDEVINFO info, SP_DEVINFO_
     TCHAR buffer[buffer_size];
     SetupDiGetDeviceInstanceId(info, data, buffer, buffer_size, NULL);
 }
+
+void uninitvar_localtime_s(const time_t *time, struct tm *result)
+{
+    time_t uninit_time;
+    struct tm uninit_result;
+    // cppcheck-suppress uninitvar
+    (void)localtime_s(result, &uninit_time);
+    (void)localtime_s(&uninit_result, time);
+    (void)localtime_s(result, time);
+}
+
+void nullPointer_localtime_s(const time_t *time, struct tm *result)
+{
+    // cppcheck-suppress nullPointer
+    (void)localtime_s(result, NULL);
+    // cppcheck-suppress nullPointer
+    (void)localtime_s(NULL, time);
+    (void)localtime_s(result, time);
+}
+
+void memleak_localtime_s(void) // #9258
+{
+    const time_t t = time(0);
+    struct tm *const now = new tm();
+    if (localtime_s(now, &t) == 0)
+        printf("%d\n", now->tm_mday);
+    // cppcheck-suppress memleak
+}