[clang] [analyzer] Match dangling subobjects by their base region in DanglingPtrDeref (PR #211552)

[Gábor Horváth via cfe-commits]

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@@ -112,3 +112,56 @@ void inlined_callee_single_report() {
   // expected-note at -1 {{Calling 'deref_param'}}
   (void)r;
 }
+
+struct MyBuffer {
+  char buffer[8];
+};
+
+void member_subregion_dangling_deref() {
+  const char *p = nullptr;
+  {
+    struct MyBuffer tmp_buffer = {};
+    p = tmp_buffer.buffer;
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Xazax-hun wrote:

Could we maybe add some pointer arithmetic, so we don't only point to the first element of the array?

https://github.com/llvm/llvm-project/pull/211552