[clang] [mlir] [lld] [llvm] [flang] [ELF] Merge exportDynamic into versionId (PR #71272)

[Peter Smith via cfe-commits]

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@@ -316,9 +308,25 @@ class Symbol {
   // This field is a index to the symbol's version definition.
   uint16_t verdefIndex;
 
-  // Version definition index.
-  uint16_t versionId;
+  // Used by a Defined symbol with protected or default visibility, to record
+  // the verdef index and whether the symbol is exported into .dynsym.
+  // * -1 (initial): not exported, binding unchanged
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smithp35 wrote:

Is it work saying -1u as the field is uint16_t?

I guess this means that we'll not be able to support a program with 65535 symbol versions. Probably not likely to encounter that in practice.

https://github.com/llvm/llvm-project/pull/71272