[PATCH] D135375: [analyzer] Initialize regions returned by CXXNew to undefined

[Kristóf Umann via Phabricator via cfe-commits]

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Discourse mail: https://discourse.llvm.org/t/analyzer-why-do-we-suck-at-modeling-c-dynamic-memory/65667

`malloc()` returns a piece of uninitialized dynamic memory. We were (almost) always to model this behaviour. Its C++ counterpart, `operator new` is a lot more complex, because it allows for initialization, the most complicated of which the usage of constructors.

We gradually became better in modeling constructors, but for some reason, most likely for reasons lost in history, we never actually modeled the case when the memory returned by `operator new` was just simply uninitialized. This patch (attempts) to fix this tiny little error.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D135375

Files:
  clang/lib/StaticAnalyzer/Core/ExprEngineCXX.cpp
  clang/test/Analysis/NewDelete-checker-test.cpp
  clang/test/Analysis/cxx-member-initializer-const-field.cpp
  clang/test/Analysis/new-ctor-conservative.cpp
  clang/test/Analysis/new-ctor-recursive.cpp
  clang/test/Analysis/new.cpp
  clang/test/Analysis/placement-new.cpp
  clang/test/Analysis/reinterpret-cast.cpp
  clang/test/Analysis/uninit-const.cpp

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