[PATCH] D53864: [ELF] - Do not crash when -r output uses linker script with `/DISCARD/`

[Peter Smith via Phabricator via llvm-commits]

peter.smith added a comment.

I can confirm that this change does fix the problem observed in pr39493.



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Comment at: ELF/InputFiles.cpp:648
     // but just copy relocation sections to output.
-    if (Config->Relocatable)
-      return make<InputSection>(*this, Sec, Name);
+    if (Config->Relocatable) {
+      InputSection *RelocSec = make<InputSection>(*this, Sec, Name);
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This bit of code looks like it could be merged with if (Config->EmitRelocs) on line 692

By doing so we wouldn't be skipping the code at 672 for Config->Relocatable I don't think that this code has any side-effects that would affect a discarded section though.


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Comment at: ELF/InputFiles.cpp:652
+      // -emit-relocs below. This is useful for case when linker script contains
+      // the "/DISCARD/". It is uncommon to have script with -r, but arm64 linux
+      // kernel use it and we have to handle such case and do not crash.
----------------
My understanding is that it is all Linux kernel modules use that fragment of linker script and not just arm64.


https://reviews.llvm.org/D53864