[analyzer] Add PlacementNewChecker

Summary:
This checker verifies if default placement new is provided with pointers
to sufficient storage capacity.

Noncompliant Code Example:
  #include <new>
  void f() {
    short s;
    long *lp = ::new (&s) long;
  }

Based on SEI CERT rule MEM54-CPP
https://wiki.sei.cmu.edu/confluence/display/cplusplus/MEM54-CPP.+Provide+placement+new+with+properly+aligned+pointe
This patch does not implement checking of the alignment.

Reviewers: NoQ, xazax.hun

Subscribers: mgorny, whisperity, xazax.hun, baloghadamsoftware, szepet,
rnkovacs, a.sidorin, mikhail.ramalho, donat

Tags: #clang

Differential Revision: https://reviews.llvm.org/D71612

1 files changed, 22 insertions, 0 deletions

diff --git a/clang/test/Analysis/placement-new-user-defined.cpp b/clang/test/Analysis/placement-new-user-defined.cpp
new file mode 100644
index 00000000000..b3fe47057f8
--- /dev/null
+++ b/clang/test/Analysis/placement-new-user-defined.cpp
@@ -0,0 +1,22 @@
+// RUN: %clang_analyze_cc1 -std=c++11 %s \
+// RUN:   -analyzer-checker=core \
+// RUN:   -analyzer-checker=cplusplus.NewDelete \
+// RUN:   -analyzer-checker=cplusplus.PlacementNew \
+// RUN:   -analyzer-output=text -verify \
+// RUN:   -triple x86_64-unknown-linux-gnu
+
+// expected-no-diagnostics
+
+#include "Inputs/system-header-simulator-cxx.h"
+
+struct X {
+  static void *operator new(std::size_t sz, void *b) {
+    return ::operator new(sz, b);
+  }
+  long l;
+};
+void f() {
+  short buf;
+  X *p1 = new (&buf) X;
+  (void)p1;
+}