Index: clang-tools-extra/clang-tidy/bugprone/BugproneTidyModule.cpp
===================================================================
--- clang-tools-extra/clang-tidy/bugprone/BugproneTidyModule.cpp
+++ clang-tools-extra/clang-tidy/bugprone/BugproneTidyModule.cpp
@@ -35,6 +35,7 @@
 #include "MoveForwardingReferenceCheck.h"
 #include "MultipleStatementMacroCheck.h"
 #include "NoEscapeCheck.h"
+#include "NonportableintegerconstantCheck.h"
 #include "NotNullTerminatedResultCheck.h"
 #include "ParentVirtualCallCheck.h"
 #include "PosixReturnCheck.h"
@@ -120,6 +121,8 @@
         "bugprone-move-forwarding-reference");
     CheckFactories.registerCheck<MultipleStatementMacroCheck>(
         "bugprone-multiple-statement-macro");
+    CheckFactories.registerCheck<NonportableintegerconstantCheck>(
+        "bugprone-non-portable-integer-constant");
     CheckFactories.registerCheck<RedundantBranchConditionCheck>(
         "bugprone-redundant-branch-condition");
     CheckFactories.registerCheck<cppcoreguidelines::NarrowingConversionsCheck>(
Index: clang-tools-extra/clang-tidy/bugprone/CMakeLists.txt
===================================================================
--- clang-tools-extra/clang-tidy/bugprone/CMakeLists.txt
+++ clang-tools-extra/clang-tidy/bugprone/CMakeLists.txt
@@ -31,6 +31,7 @@
   MultipleStatementMacroCheck.cpp
   NoEscapeCheck.cpp
   NotNullTerminatedResultCheck.cpp
+  NonportableintegerconstantCheck.cpp
   ParentVirtualCallCheck.cpp
   PosixReturnCheck.cpp
   RedundantBranchConditionCheck.cpp
Index: clang-tools-extra/clang-tidy/bugprone/NonportableintegerconstantCheck.h
===================================================================
--- /dev/null
+++ clang-tools-extra/clang-tidy/bugprone/NonportableintegerconstantCheck.h
@@ -0,0 +1,34 @@
+//===--- NonportableintegerconstantCheck.h - clang-tidy ---------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_NON_PORTABLE_INTEGER_CONSTANT_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_NON_PORTABLE_INTEGER_CONSTANT_H
+
+#include "../ClangTidyCheck.h"
+
+namespace clang {
+namespace tidy {
+namespace bugprone {
+
+/// Finds masks that are being used in a nonportable manner
+///
+/// For the user-facing documentation see:
+/// http://clang.llvm.org/extra/clang-tidy/checks/bugprone-non-portable-integer-constant.html
+class NonportableintegerconstantCheck : public ClangTidyCheck {
+public:
+  NonportableintegerconstantCheck(StringRef Name, ClangTidyContext *Context)
+      : ClangTidyCheck(Name, Context) {}
+  void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+  void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+};
+
+} // namespace bugprone
+} // namespace tidy
+} // namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_NON_PORTABLE_INTEGER_CONSTANT_H
Index: clang-tools-extra/clang-tidy/bugprone/NonportableintegerconstantCheck.cpp
===================================================================
--- /dev/null
+++ clang-tools-extra/clang-tidy/bugprone/NonportableintegerconstantCheck.cpp
@@ -0,0 +1,70 @@
+//===--- NonportableintegerconstantCheck.cpp - clang-tidy ----------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "NonportableintegerconstantCheck.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/Decl.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/Lex/Lexer.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang {
+namespace tidy {
+namespace bugprone {
+
+/// The mask is problematic if:
+/// - The highest bit is set and everything else are zeroes, for example: `0x80000000`.
+/// - All the bits are set to one, for example: `0xFFFFFFFF`.
+bool isProblematicMask(StringRef HexNumber) {
+
+ // Check whether only the highest bit is set.
+  if (HexNumber[0] == '8' && HexNumber[1] == '0') {
+    // Consume the first non-zero.
+    HexNumber = HexNumber.drop_front();
+    // Consume all the left zeroes.
+    HexNumber = HexNumber.drop_while([](char C) { return C == '0'; });
+    return HexNumber.empty();
+  }
+
+  // Check whether all the bits are set to one by consuming all the 'F's.
+  HexNumber = HexNumber.drop_while([](char C) { return C == 'F' || C == 'f'; });
+  return HexNumber.empty();
+}
+
+void NonportableintegerconstantCheck::registerMatchers(MatchFinder *Finder) {
+  Finder->addMatcher(integerLiteral().bind("integer"), this);
+}
+
+void NonportableintegerconstantCheck::check(const MatchFinder::MatchResult &Result) {
+
+  const auto *MatchedInt = Result.Nodes.getNodeAs<IntegerLiteral>("integer");
+
+  if (MatchedInt) {
+
+    StringRef MaskStr = Lexer::getSourceText(
+        CharSourceRange::getTokenRange(MatchedInt->getSourceRange()),
+        *Result.SourceManager, Result.Context->getLangOpts(), 0);
+
+    MaskStr = StringRef(MaskStr.lower());
+    if (!MaskStr.consume_front("0x"))
+      return;
+
+    MaskStr = MaskStr.take_while(llvm::isHexDigit);
+
+    if (!isProblematicMask(MaskStr))
+      return;
+
+    diag(MatchedInt->getBeginLoc(),
+         "integer is being used in a non-portable manner ");
+  }
+}
+
+} // namespace bugprone
+} // namespace tidy
+} // namespace clang
\ No newline at end of file
Index: clang-tools-extra/clang-tidy/cert/CERTTidyModule.cpp
===================================================================
--- clang-tools-extra/clang-tidy/cert/CERTTidyModule.cpp
+++ clang-tools-extra/clang-tidy/cert/CERTTidyModule.cpp
@@ -10,6 +10,7 @@
 #include "../ClangTidyModule.h"
 #include "../ClangTidyModuleRegistry.h"
 #include "../bugprone/BadSignalToKillThreadCheck.h"
+#include "../bugprone/NonPortableIntegerConstant.h"
 #include "../bugprone/ReservedIdentifierCheck.h"
 #include "../bugprone/SignedCharMisuseCheck.h"
 #include "../bugprone/SpuriouslyWakeUpFunctionsCheck.h"
@@ -102,6 +103,9 @@
     CheckFactories.registerCheck<misc::NonCopyableObjectsCheck>("cert-fio38-c");
     // ERR
     CheckFactories.registerCheck<StrToNumCheck>("cert-err34-c");
+    // INT
+    CheckFactories.registerCheck<bugprone::NonPortableIntegerConstant>(
+        "cert-int17-c");
     // MSC
     CheckFactories.registerCheck<LimitedRandomnessCheck>("cert-msc30-c");
     CheckFactories.registerCheck<ProperlySeededRandomGeneratorCheck>(
Index: clang-tools-extra/docs/ReleaseNotes.rst
===================================================================
--- clang-tools-extra/docs/ReleaseNotes.rst
+++ clang-tools-extra/docs/ReleaseNotes.rst
@@ -72,7 +72,7 @@
   :doc:`cppcoreguidelines-init-variables
   <clang-tidy/checks/cppcoreguidelines-init-variables>` and
   :doc:`modernize-make-unique <clang-tidy/checks/modernize-make-unique>`.
-
+  
 New modules
 ^^^^^^^^^^^
 
@@ -110,6 +110,19 @@
   <clang-tidy/checks/readability-function-cognitive-complexity>` check.
 
   Flags functions with Cognitive Complexity metric exceeding the configured limit.
+ 
+- New :doc:`bugprone-non-portable-integer-constant	
+  <clang-tidy/checks/bugprone-non-portable-integer-constant>` check.	
+  
+  Finds masks that are being used in a non-portable manner.	
+
+New check aliases
+^^^^^^^^^^^^^^^^^
+
+- New alias :doc:`cert-int17-c
+  <clang-tidy/checks/cert-int17-c>` to
+  :doc:`bugprone-non-portable-integer-constant
+  <clang-tidy/checks/bugprone-non-portable-integer-constant>` was added.
 
 Changes in existing checks
 ^^^^^^^^^^^^^^^^^^^^^^^^^^
Index: clang-tools-extra/docs/clang-tidy/checks/bugprone-non-portable-integer-constant.rst
===================================================================
--- /dev/null
+++ clang-tools-extra/docs/clang-tidy/checks/bugprone-non-portable-integer-constant.rst
@@ -0,0 +1,14 @@
+.. title:: clang-tidy - bugprone-non-portable-integer-constant
+
+bugprone-non-portable-integer-constant
+===================================
+
+Finds masks that are being used in a non-portable manner.
+
+.. code-block:
+
+    const unsigned long mask = 0xFFFFFFFF;
+    
+    unsigned long flipbits(unsigned long x) {
+      return x ^ mask;
+    }
\ No newline at end of file
Index: clang-tools-extra/docs/clang-tidy/checks/cert-int17-c.rst
===================================================================
--- /dev/null
+++ clang-tools-extra/docs/clang-tidy/checks/cert-int17-c.rst
@@ -0,0 +1,10 @@
+.. title:: clang-tidy - cert-int17-c
+.. meta::
+   :http-equiv=refresh: 5;URL=bugprone-non-portable-integer-constant.html
+
+cert-int17-c
+==============
+
+The cert-int17-c check is an alias, please see
+`bugprone-non-portable-integer-constant <bugprone-non-portable-integer-constant.html>`_
+for more information.
Index: clang-tools-extra/docs/clang-tidy/checks/list.rst
===================================================================
--- clang-tools-extra/docs/clang-tidy/checks/list.rst
+++ clang-tools-extra/docs/clang-tidy/checks/list.rst
@@ -72,6 +72,7 @@
    `bugprone-move-forwarding-reference <bugprone-move-forwarding-reference.html>`_, "Yes"
    `bugprone-multiple-statement-macro <bugprone-multiple-statement-macro.html>`_,
    `bugprone-no-escape <bugprone-no-escape.html>`_,
+   `bugprone-non-portable-integer-constant <bugprone-non-portable-integer-constant.html>`_,
    `bugprone-not-null-terminated-result <bugprone-not-null-terminated-result.html>`_, "Yes"
    `bugprone-parent-virtual-call <bugprone-parent-virtual-call.html>`_, "Yes"
    `bugprone-posix-return <bugprone-posix-return.html>`_, "Yes"
@@ -110,6 +111,7 @@
    `cert-err58-cpp <cert-err58-cpp.html>`_,
    `cert-err60-cpp <cert-err60-cpp.html>`_,
    `cert-flp30-c <cert-flp30-c.html>`_,
+   `cert-int17-c <cert-int17-c.html>`_,
    `cert-mem57-cpp <cert-mem57-cpp.html>`_,
    `cert-msc50-cpp <cert-msc50-cpp.html>`_,
    `cert-msc51-cpp <cert-msc51-cpp.html>`_,
Index: clang-tools-extra/test/clang-tidy/checkers/bugprone-non-portable-integer-constant.cpp
===================================================================
--- /dev/null
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone-non-portable-integer-constant.cpp
@@ -0,0 +1,33 @@
+// RUN: %check_clang_tidy %s bugprone-non-portable-integer-constant %t
+
+// #define ULONG_MAX 0xFFFFFFFFUL
+#include <limits.h>
+#include <stdio.h>
+
+const unsigned long mask = 0xFFFFFFFF;
+// CHECK-MESSAGES: :[[@LINE-1]]:28: warning: integer is being used in a non-portable manner 
+
+const unsigned long mask1 = 0xffffffffUL;
+// CHECK-MESSAGES: :[[@LINE-1]]:29: warning: integer is being used in a non-portable manner
+
+const unsigned long mask2 = 0x80000000;
+// CHECK-MESSAGES: :[[@LINE-1]]:29: warning: integer is being used in a non-portable manner 
+
+int stuff() {
+  int mask3 = 0xff;
+  // CHECK-MESSAGES: :[[@LINE-1]]:15: warning: integer is being used in a non-portable manner
+  int value = 0x55;
+  return mask3;
+}
+
+const unsigned long g = 0xC0;
+// no warnings
+
+const unsigned long x = -1;
+// no warnings
+
+const unsigned long y = ~(ULONG_MAX >> 1);
+// no warnings
+
+const unsigned long z = 0x11111111;
+// no warnings