Index: clang-tidy/cppcoreguidelines/CMakeLists.txt
===================================================================
--- clang-tidy/cppcoreguidelines/CMakeLists.txt
+++ clang-tidy/cppcoreguidelines/CMakeLists.txt
@@ -2,6 +2,7 @@
 
 add_clang_library(clangTidyCppCoreGuidelinesModule
   CppCoreGuidelinesTidyModule.cpp
+  ProBoundsArrayToPointerDecayCheck.cpp
   ProTypeConstCastCheck.cpp
   ProTypeReinterpretCastCheck.cpp
 
Index: clang-tidy/cppcoreguidelines/CppCoreGuidelinesTidyModule.cpp
===================================================================
--- clang-tidy/cppcoreguidelines/CppCoreGuidelinesTidyModule.cpp
+++ clang-tidy/cppcoreguidelines/CppCoreGuidelinesTidyModule.cpp
@@ -10,6 +10,7 @@
 #include "../ClangTidy.h"
 #include "../ClangTidyModule.h"
 #include "../ClangTidyModuleRegistry.h"
+#include "ProBoundsArrayToPointerDecayCheck.h"
 #include "ProTypeConstCastCheck.h"
 #include "ProTypeReinterpretCastCheck.h"
 
@@ -21,6 +22,8 @@
 class CppCoreGuidelinesModule : public ClangTidyModule {
 public:
   void addCheckFactories(ClangTidyCheckFactories &CheckFactories) override {
+    CheckFactories.registerCheck<ProBoundsArrayToPointerDecayCheck>(
+        "cppcoreguidelines-pro-bounds-array-to-pointer-decay");
     CheckFactories.registerCheck<ProTypeConstCastCheck>(
         "cppcoreguidelines-pro-type-const-cast");
     CheckFactories.registerCheck<ProTypeReinterpretCastCheck>(
Index: clang-tidy/cppcoreguidelines/ProBoundsArrayToPointerDecayCheck.h
===================================================================
--- /dev/null
+++ clang-tidy/cppcoreguidelines/ProBoundsArrayToPointerDecayCheck.h
@@ -0,0 +1,34 @@
+//===--- ProBoundsArrayToPointerDecayCheck.h - clang-tidy--------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CPPCOREGUIDELINES_PRO_BOUNDS_ARRAY_TO_POINTER_DECAY_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CPPCOREGUIDELINES_PRO_BOUNDS_ARRAY_TO_POINTER_DECAY_H
+
+#include "../ClangTidy.h"
+
+namespace clang {
+namespace tidy {
+
+/// This check flags all array to pointer decays
+///
+/// For the user-facing documentation see:
+/// http://clang.llvm.org/extra/clang-tidy/checks/cppcoreguidelines-pro-bounds-array-to-pointer-decay.html
+class ProBoundsArrayToPointerDecayCheck : public ClangTidyCheck {
+public:
+  ProBoundsArrayToPointerDecayCheck(StringRef Name, ClangTidyContext *Context)
+      : ClangTidyCheck(Name, Context) {}
+  void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+  void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+};
+
+} // namespace tidy
+} // namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CPPCOREGUIDELINES_PRO_BOUNDS_ARRAY_TO_POINTER_DECAY_H
+
Index: clang-tidy/cppcoreguidelines/ProBoundsArrayToPointerDecayCheck.cpp
===================================================================
--- /dev/null
+++ clang-tidy/cppcoreguidelines/ProBoundsArrayToPointerDecayCheck.cpp
@@ -0,0 +1,45 @@
+//===--- ProBoundsArrayToPointerDecayCheck.cpp - clang-tidy----------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ProBoundsArrayToPointerDecayCheck.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang {
+namespace tidy {
+
+void ProBoundsArrayToPointerDecayCheck::registerMatchers(MatchFinder *Finder) {
+  if (!getLangOpts().CPlusPlus)
+    return;
+
+  // The only allowed array to pointer decay if
+  // 1) just before array subscription
+  // 2) inside a range-for over an array
+  // 3) it converts a string literal to a pointer
+  Finder->addMatcher(
+      implicitCastExpr(unless(hasParent(arraySubscriptExpr())),
+                       unless(hasSourceExpression(declRefExpr(to(varDecl(hasName("__range")))))),
+                       unless(hasSourceExpression(stringLiteral()))
+                      ).bind("cast"),
+      this);
+}
+
+void ProBoundsArrayToPointerDecayCheck::check(const MatchFinder::MatchResult &Result) {
+  const auto *MatchedCast = Result.Nodes.getNodeAs<ImplicitCastExpr>("cast");
+  if (MatchedCast->getCastKind() != CK_ArrayToPointerDecay)
+    return;
+
+  diag(MatchedCast->getExprLoc(), "do not (implicitly) convert an array to a pointer; use gsl::array_view instead");
+}
+
+} // namespace tidy
+} // namespace clang
+
Index: docs/clang-tidy/checks/cppcoreguidelines-pro-bounds-array-to-pointer-decay.rst
===================================================================
--- /dev/null
+++ docs/clang-tidy/checks/cppcoreguidelines-pro-bounds-array-to-pointer-decay.rst
@@ -0,0 +1,9 @@
+cppcoreguidelines-pro-bounds-array-to-pointer-decay
+===================================================
+
+This check flags all array to pointer decays.
+
+Pointers should not be used as arrays. array_view is a bounds-checked, safe alternative to using pointers to access arrays.
+
+This rule is part of the "Bounds safety" profile of the C++ Core Guidelines, see
+https://github.com/isocpp/CppCoreGuidelines/blob/master/CppCoreGuidelines.md#-bounds3-no-array-to-pointer-decay
Index: docs/clang-tidy/checks/list.rst
===================================================================
--- docs/clang-tidy/checks/list.rst
+++ docs/clang-tidy/checks/list.rst
@@ -4,6 +4,7 @@
 .. toctree::
    cert-setlongjmp
    cert-variadic-function-def
+   cppcoreguidelines-pro-bounds-array-to-pointer-decay
    cppcoreguidelines-pro-type-const-cast
    cppcoreguidelines-pro-type-reinterpret-cast
    google-build-explicit-make-pair
Index: test/clang-tidy/cppcoreguidelines-pro-bounds-array-to-pointer-decay.cpp
===================================================================
--- /dev/null
+++ test/clang-tidy/cppcoreguidelines-pro-bounds-array-to-pointer-decay.cpp
@@ -0,0 +1,44 @@
+// RUN: %python %S/check_clang_tidy.py %s cppcoreguidelines-pro-bounds-array-to-pointer-decay %t
+#include <stddef.h>
+
+namespace gsl {
+  template<class T>
+  class array_view {
+  public:
+    template< class U, size_t N >
+    array_view( U (&arr)[N] );
+  };
+}
+
+void pointerfun(int* p);
+void arrayfun(int p[]);
+void arrayviewfun(gsl::array_view<int> &p);
+size_t s();
+
+void f()
+{
+  int a[5];
+  pointerfun(a);
+  // CHECK-MESSAGES: :[[@LINE-1]]:14: warning: do not (implicitly) convert an array to a pointer; use gsl::array_view instead [cppcoreguidelines-pro-bounds-array-to-pointer-decay]
+  pointerfun((int*)a);
+  // CHECK-MESSAGES: :[[@LINE-1]]:20: warning: do not (implicitly) convert an array to a pointer; use gsl::array_view instead
+  arrayfun(a);
+  // CHECK-MESSAGES: :[[@LINE-1]]:12: warning: do not (implicitly) convert an array to a pointer; use gsl::array_view instead
+
+  pointerfun(a + s() - 10); // Convert to &a[g() - 10];
+  // CHECK-MESSAGES: :[[@LINE-1]]:14: warning: do not (implicitly) convert an array to a pointer; use gsl::array_view instead
+
+  gsl::array_view<int> av(a);
+  arrayviewfun(av); // OK
+
+  int i = a[0]; // OK
+  pointerfun(&a[0]); // OK
+
+  for(auto e : a ) // OK, iteration internally decays array to pointer
+    ;
+}
+
+const char* g()
+{
+    return "clang"; // OK, decay string literal to pointer
+}