[llvm] [Support] mmap when possible in getSTDIN. (PR #162013)

[Yanzuo Liu via llvm-commits]

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@@ -175,7 +175,8 @@ int main(int argc, char **argv) {
 
   for (const auto &File : InputFileNames) {
     ErrorOr<std::unique_ptr<MemoryBuffer>> Buffer =
-        MemoryBuffer::getFileOrSTDIN(File, /*IsText=*/true);
+        MemoryBuffer::getFileOrSTDIN(File, /*IsText=*/true,
+                                     /*RequiresNullTerminator*/ false);
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zwuis wrote:

`/*RequiresNullTerminator=*/false`

https://github.com/llvm/llvm-project/pull/162013