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

[Yingwei Zheng 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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dtcxzyw wrote:

> then describes the flags you can use to disable the optimization, then describes the specific patterns we're special-casing.

Done.


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