[clang] [Clang][CodeGen] Do not set inbounds flag for struct GEP with null base pointers (PR #130734)

[Eli Friedman via cfe-commits]

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@@ -42,6 +42,11 @@ Potentially Breaking Changes
 C/C++ Language Potentially Breaking Changes
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+- Some old-style offsetof idioms like ``((int)(&(((struct S *)0)->field)))`` are treated
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efriedma-quic wrote:

I think it would be more helpful for users if the release note starts out by saying "we're optimizing null pointers more aggressively", then describes the flags you can use to disable the optimization, then describes the specific patterns we're special-casing.

https://github.com/llvm/llvm-project/pull/130734