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

[Alexandre Ganea via llvm-commits]

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@@ -0,0 +1,8 @@
+# RUN: llvm-mc -filetype=obj -triple=i386-pc-win32 %s -o %t
+# RUN: env LLD_IN_TEST=1 not lld-link %t /out:/dev/null /fat-lto-objects 2>&1 | FileCheck %s
+
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aganea wrote:

Are you able to handle a COFF error here as well? For example, when dealing with a FAT LTO .OBJ, any of the `object_error::parse_failed` returned by `COFFObjectFile::initialize`? 

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