--- distlib-0.3.4/PC/launcher.c.orig	2022-06-05 10:51:32.831156800 +0200
+++ distlib-0.3.4/PC/launcher.c	2022-06-05 10:51:39.799617800 +0200
@@ -30,6 +30,82 @@
 #include <stdio.h>
 #include <windows.h>
 #include <Shlwapi.h>
+#include <errno.h>
+
+static errno_t _mingw__wdupenv_s(wchar_t **buffer, size_t *numberOfElements,
+                                 const wchar_t *varname) {
+  size_t requiredSize = 0;
+  errno_t status = 0;
+  wchar_t *tmpBuffer = NULL;
+
+  // Reuse the error cases of _wgetenv_s
+  if (buffer == NULL) {
+    return _wgetenv_s(&requiredSize, NULL, 1, L"");
+  }
+
+  // XXX: We could reuse the error case of _wgetenv_s() here too, but it doesn't
+  // error out in case of NULL varname, despite saying so in the docs.
+  // So do it manually, which means no invalid parameter handler is called
+  if (varname == NULL) {
+    *buffer = NULL;
+    if (numberOfElements) {
+      *numberOfElements = 0;
+    }
+    errno = EINVAL;
+    return EINVAL;
+  }
+
+  while (1) {
+    // Implemented in a loop since the env var could change/get removed
+    // between allocating and fetching, so we have to retry.
+
+    if (requiredSize != 0) {
+      tmpBuffer = (wchar_t *)malloc(requiredSize * sizeof(wchar_t));
+      if (tmpBuffer == NULL) {
+        *buffer = NULL;
+        if (numberOfElements) {
+          *numberOfElements = 0;
+        }
+        return ENOMEM;
+      }
+    } else {
+      tmpBuffer = NULL;
+    }
+
+    status = _wgetenv_s(&requiredSize, tmpBuffer, requiredSize, varname);
+    if (status == 0 && requiredSize == 0) {
+      // env var doesn't exist
+      free(tmpBuffer);
+      tmpBuffer = NULL;
+      break;
+    } else if (status == 0 && tmpBuffer == NULL) {
+      // first call for getting the buffer size
+      continue;
+    } else if (status == ERANGE) {
+      // retry with larger buffer
+      free(tmpBuffer);
+      tmpBuffer = NULL;
+    } else {
+      // either we failed, or we are done
+      break;
+    }
+  };
+
+  if (status != 0) {
+    free(tmpBuffer);
+  } else {
+    *buffer = tmpBuffer;
+    if (numberOfElements) {
+      *numberOfElements = requiredSize;
+    }
+  }
+
+  return status;
+}
+
+#if defined(__MINGW32__) && !defined(_UCRT)
+#define _wdupenv_s _mingw__wdupenv_s
+#endif
 
 #pragma comment (lib, "Shlwapi.lib")