[clang] [lld] [llvm] Add FatLTO support for COFF (PR #165529)

[Alexandre Ganea via llvm-commits]

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@@ -256,6 +257,23 @@ MemoryBufferRef LinkerDriver::takeBuffer(std::unique_ptr<MemoryBuffer> mb) {
   return mbref;
 }
 
+InputFile *LinkerDriver::tryCreateFatLTOFile(MemoryBufferRef mb,
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aganea wrote:

I don't think we need this as a member function, it could just be `static`.

Additionnaly, can we also handle the `ObjFile::create` call in this function?

https://github.com/llvm/llvm-project/pull/165529