mimalloc: allow running in Windows Nano Server containers

The `GetNumaProcessorNode()` symbol is not defined in Nano Server's DLLs
(because that function is long deprecated). This caused Git no longer to
work on Nano Server.

Instead of importing it statically, try to import it dynamically, and
fall back gracefully if it cannot be loaded.

This fixes #4052

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

compat/mimalloc/os.c

@@ -166,9 +166,11 @@ typedef struct MI_PROCESSOR_NUMBER_S { WORD Group; BYTE Number; BYTE Reserved; }
 typedef VOID (__stdcall *PGetCurrentProcessorNumberEx)(MI_PROCESSOR_NUMBER* ProcNumber);
 typedef BOOL (__stdcall *PGetNumaProcessorNodeEx)(MI_PROCESSOR_NUMBER* Processor, PUSHORT NodeNumber);
 typedef BOOL (__stdcall* PGetNumaNodeProcessorMaskEx)(USHORT Node, PGROUP_AFFINITY ProcessorMask);
+typedef BOOL (__stdcall *PGetNumaProcessorNode)(UCHAR Processor, PUCHAR NodeNumber);
 static PGetCurrentProcessorNumberEx pGetCurrentProcessorNumberEx = NULL;
 static PGetNumaProcessorNodeEx      pGetNumaProcessorNodeEx = NULL;
 static PGetNumaNodeProcessorMaskEx  pGetNumaNodeProcessorMaskEx = NULL;
+static PGetNumaProcessorNode        pGetNumaProcessorNode = NULL;
 
 static bool mi_win_enable_large_os_pages(void)
 {
@@ -234,6 +236,7 @@ void _mi_os_init(void)
     pGetCurrentProcessorNumberEx = (PGetCurrentProcessorNumberEx)(void (*)(void))GetProcAddress(hDll, "GetCurrentProcessorNumberEx");
     pGetNumaProcessorNodeEx = (PGetNumaProcessorNodeEx)(void (*)(void))GetProcAddress(hDll, "GetNumaProcessorNodeEx");
     pGetNumaNodeProcessorMaskEx = (PGetNumaNodeProcessorMaskEx)(void (*)(void))GetProcAddress(hDll, "GetNumaNodeProcessorMaskEx");
+    pGetNumaProcessorNode = (PGetNumaProcessorNode)(void (*)(void))GetProcAddress(hDll, "GetNumaProcessorNode");
     FreeLibrary(hDll);
   }
   if (mi_option_is_enabled(mi_option_large_os_pages) || mi_option_is_enabled(mi_option_reserve_huge_os_pages)) {
@@ -1316,11 +1319,11 @@ static size_t mi_os_numa_nodex(void) {
     BOOL ok = (*pGetNumaProcessorNodeEx)(&pnum, &nnode);
     if (ok) numa_node = nnode;
   }
-  else {
+  else if (pGetNumaProcessorNode != NULL) {
     // Vista or earlier, use older API that is limited to 64 processors. Issue #277
     DWORD pnum = GetCurrentProcessorNumber();
     UCHAR nnode = 0;
-    BOOL ok = GetNumaProcessorNode((UCHAR)pnum, &nnode);
+    BOOL ok = pGetNumaProcessorNode((UCHAR)pnum, &nnode);
     if (ok) numa_node = nnode;
   }
   return numa_node;