[lld] [lld][ELF] Error when deplibs adds new input file after LTO (PR #98565)

[Fangrui Song via llvm-commits]

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@@ -2980,6 +2981,20 @@ template <class ELFT> void LinkerDriver::link(opt::InputArgList &args) {
   for (const DuplicateSymbol &d : ctx.duplicates)
     reportDuplicate(*d.sym, d.file, d.section, d.value);
 
+  // ELF dependent libraries may have introduced new input files after LTO has
+  // completed. This is an error if the files haven't already been parsed, since
+  // it's no longer legal to change the symbol table by parsing them.
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MaskRay wrote:

"no longer legal ..." => changing the symbol table could break the semantic assumption of LTO.

https://github.com/llvm/llvm-project/pull/98565