[PATCH] D38790: [ELF] Do not keep symbols if they referenced only from discarded sections.

[Rafael Avila de Espindola via llvm-commits]

Igor Kudrin via Phabricator <reviews at reviews.llvm.org> writes:

> Index: test/ELF/gc-sections-shared.s
> ===================================================================
> --- test/ELF/gc-sections-shared.s
> +++ test/ELF/gc-sections-shared.s
> @@ -6,7 +6,8 @@
>  # RUN: llvm-readobj --dynamic-table --dyn-symbols %t | FileCheck %s
>  
>  # This test the property that we have a needed line for every undefined.
> -# It would also be OK to drop bar2 and the need for the .so
> +# The test now is in an intermediate state, it needs to be updated
> +# when handling DT_NEEDED for dead symbols is fixed.

I don't think we should regress this.

I have moved the cleanup bits to https://reviews.llvm.org/D40315.

With that in, this patch should include the necessary changes to handle
IsNeeded with gc-sections.That way we can review the full change and not
regress any tests in the process.

Cheers,
Rafael