[llvm] [BOLT] Fix references in ignored functions in CFG state (PR #140678)

[Maksim Panchenko via llvm-commits]

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@@ -3433,6 +3433,7 @@ void RewriteInstance::disassembleFunctions() {
         BC->outs() << "BOLT-INFO: could not disassemble function " << Function
                    << ". Will ignore.\n";
       // Forcefully ignore the function.
+      Function.scanExternalRefs();
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maksfb wrote:

@paschalis-mpeis, I took a stab at isolating/moving calls to `scanExternalRefs()` and it turned out to be more complicated. I would rather do it in a separate PR that includes disambiguated the `setIgnored()` interface.

https://github.com/llvm/llvm-project/pull/140678