[llvm] [z/OS] Add z/OS archive reading support (PR #187110)

[Uyiosa Iyekekpolor via llvm-commits]

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@@ -158,6 +158,46 @@ class LLVM_ABI BigArchiveMemberHeader
   Expected<bool> isThin() const override { return false; }
 };
 
+// Define file member header of z/OS archive.
+// The fixed part of the member header (in EBCDIC) is:
+// struct ar_hdr {
+//   char ar_name[16]; /* blank terminated member name */
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uyoyo0 wrote:

These fields are padded with spaces rather than null terminated. I agree that the terminology is a bit confusing so I've updated the comment.

https://github.com/llvm/llvm-project/pull/187110