[lld] [ELF] Enhance --no-allow-shlib-undefined to report non-exported definition (PR #70769)

[Igor Kudrin via llvm-commits]

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@@ -54,6 +54,7 @@ enum {
   NEEDS_TLSGD_TO_IE = 1 << 6,
   NEEDS_GOT_DTPREL = 1 << 7,
   NEEDS_TLSIE = 1 << 8,
+  HAS_SHARED_DEF = 1 << 9,
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igorkudrin wrote:

`Symbol::flags` has a comment "Temporary flags used to communicate which symbol entries need PLT and GOT entries during postScanRelocations();". The description seems misleading with the proposed changes.

https://github.com/llvm/llvm-project/pull/70769