[clang] [clang][analyzer] Add OpaqueSTLFunctionsModeling (PR #178910)

[Balázs Benics via cfe-commits]

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@@ -0,0 +1,16 @@
+// RUN: %clang_analyze_cc1 -analyzer-checker=core,cplusplus.OpaqueSTLFunctionsModeling \
+// RUN:   -analyzer-dump-egraph=%t.dot -std=c++11 %s
+// RUN: cat %t.dot | FileCheck %s
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steakhal wrote:

```suggestion
// RUN: %clang_analyze_cc1 -analyzer-checker=core \
// RUN:   -analyzer-dump-egraph=%t.dot -std=c++11 %s
// RUN: cat %t.dot | FileCheck %s
```
The checker should be enabled by default for C++. This should be reflected in the test as well.

https://github.com/llvm/llvm-project/pull/178910