[clang] Add unique_ptr <T[]> accesses to -Wunsafe-buffer-usage (PR #156773)

[Jan Korous via cfe-commits]

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@@ -31,6 +31,20 @@ void test_unclaimed_use(int *p) { // expected-warning{{'p' is an unsafe pointer
   p[5] = 5;       // expected-note{{used in buffer access here}}
 }
 
+namespace std {
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jkorous-apple wrote:

I don't think this test is the right place to add test cases for `warn_unsafe_buffer_usage_unique_ptr_array_access`. Can we create a new separate test file?

https://github.com/llvm/llvm-project/pull/156773