1 files changed, 10 insertions, 37 deletions
diff --git a/llvm/lib/Support/Windows/Path.inc b/llvm/lib/Support/Windows/Path.inc
index 49910af55a7..c787dc2a3f8 100644
--- a/llvm/lib/Support/Windows/Path.inc
+++ b/llvm/lib/Support/Windows/Path.inc
@@ -773,49 +773,22 @@ bool home_directory(SmallVectorImpl<char> &result) {
   return getKnownFolderPath(FOLDERID_Profile, result);
 }
 
-static bool getTempDirEnvVar(const char *Var, SmallVectorImpl<char> &Res) {
-  SmallVector<wchar_t, 128> NameUTF16;
-  if (windows::UTF8ToUTF16(Var, NameUTF16))
-    return false;
-
-  SmallVector<wchar_t, 1024> Buf;
-  size_t Size = 1024;
-  do {
-    Buf.reserve(Size);
-    Size =
-        GetEnvironmentVariableW(NameUTF16.data(), Buf.data(), Buf.capacity());
-    if (Size == 0)
-      return false;
-
-    // Try again with larger buffer.
-  } while (Size > Buf.capacity());
-  Buf.set_size(Size);
-
-  if (windows::UTF16ToUTF8(Buf.data(), Size, Res))
-    return false;
-  return true;
-}
-
-static bool getTempDirEnvVar(SmallVectorImpl<char> &Res) {
-  const char *EnvironmentVariables[] = {"TMP", "TEMP", "USERPROFILE"};
-  for (const char *Env : EnvironmentVariables) {
-    if (getTempDirEnvVar(Env, Res))
-      return true;
-  }
-  return false;
-}
-
 void system_temp_directory(bool ErasedOnReboot, SmallVectorImpl<char> &Result) {
   (void)ErasedOnReboot;
-  Result.clear();
 
-  // Check whether the temporary directory is specified by an environment
-  // variable.
-  if (getTempDirEnvVar(Result))
-    return;
+  wchar_t Path[MAX_PATH + 2]; // GetTempPath can return MAX_PATH + 1 + null
+  if (auto PathLength = ::GetTempPathW(sizeof(Path) / sizeof(wchar_t), Path)) {
+    assert(PathLength > 0 && PathLength <= (MAX_PATH + 1) &&
+           "GetTempPath returned undocumented result");
+    if (Path[PathLength - 1] == L'\\')
+      --PathLength; // skip trailing "\" added by GetTempPath
+    if (!UTF16ToUTF8(Path, PathLength, Result))
+      return;
+  }
 
   // Fall back to a system default.
   const char *DefaultResult = "C:\\TEMP";
+  Result.clear();
   Result.append(DefaultResult, DefaultResult + strlen(DefaultResult));
 }
 } // end namespace path