[lld] [ELF] Fix unnecessary inclusion of unreferenced provide symbols (PR #84512)

[Fangrui Song via llvm-commits]

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@@ -1570,7 +1578,10 @@ Expr ScriptParser::readPrimary() {
     tok = unquote(tok);
   else if (!isValidSymbolName(tok))
     setError("malformed number: " + tok);
-  script->referencedSymbols.push_back(tok);
+  if (activeProvideSym)
+    script->provideMap[activeProvideSym.value()].push_back(tok);
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MaskRay wrote:

`*activeProvideSym`

https://github.com/llvm/llvm-project/pull/84512