[llvm] [ThinLTO] Don't mark calloc function dead (PR #72673)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,35 @@
+; RUN: opt -module-summary %s -o %t1.bc
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MaskRay wrote:

Perhaps add a file-level comment that this is similar to `builtin-nostrip.ll`

https://github.com/llvm/llvm-project/pull/72673