[llvm] [llvm][Support][Memory] Add memfd based fallback for strict W^X Linux systems (PR #98538)

[via llvm-commits]

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@@ -526,6 +526,7 @@ class raw_fd_ostream : public raw_pwrite_stream {
   /// this closes the file when the stream is destroyed. If FD is for stdout or
   /// stderr, it will not be closed.
   raw_fd_ostream(int fd, bool shouldClose, bool unbuffered = false,
+                 bool simpleStream = false,
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minipli-oss wrote:

Yeah, makes sense. I'll fix up documenting the other options as well.

https://github.com/llvm/llvm-project/pull/98538