fix cppcorecheck warnings (#703)

* Added c++17 test configurations for clang5.0 and clang6.0

* Fixed CppCoreCheck warnings in GSL and tests

- Added CMakeSettings.json for VS Open Folder configuration
	- So we can easily run CppCoreCheck in VS
- Fixed CppCorecheck warnings where it made sense
- Suppressed the rest
	- Some suppression does not work due to compiler/tool bugs,
          so replaced by #pragma disable
	- CppCoreCheck has noise, suppressed those with comments
	- Catch produces many warnings, blanket-supressed them all
- Had to fix clang formatting to keep attributes in place
	- clang-format does not support attributes, so I am using
        - "CommentPragmas: '^ NO-FORMAT:'" to skip formatiting on them
- Removed GSL_NOEXCEPT macro, removed incorred noexcepts

* Ignore unknown attributes

* ignore unknown attributes in noexception mode tests

* fixed C26472 in at()

* created GSL_SUPPRESS macro to allow all compilers to parse suppression attributes

* try to fix gcc compilation problems with attributes

* ignore gsl::suppress for gcc

* move suppression to function level on return statements

clang5.0 and up does not allow attributes on return statemets in constexpr functions

* move suppression to function level on return statements

* use GSL_SUPPRESS in algorithm_tests

* Addressed PR comments

7 files changed, 437 insertions, 367 deletions

diff --git a/include/gsl/gsl_algorithm b/include/gsl/gsl_algorithm
index 710792f..c2ba31f 100644
--- a/include/gsl/gsl_algorithm
+++ b/include/gsl/gsl_algorithm
@@ -31,15 +31,12 @@
 #pragma warning(disable : 4127) // conditional expression is constant
 #pragma warning(disable : 4996) // unsafe use of std::copy_n
 
-// blanket turn off warnings from CppCoreCheck for now
-// so people aren't annoyed by them when running the tool.
-// more targeted suppressions will be added in a future update to the GSL
-#pragma warning(disable : 26481 26482 26483 26485 26490 26491 26492 26493 26495)
 #endif // _MSC_VER
 
 namespace gsl
 {
-
+// Note: this will generate faster code than std::copy using span iterator in older msvc+stl
+// not necessary for msvc since VS2017 15.8 (_MSC_VER >= 1915)
 template <class SrcElementType, std::ptrdiff_t SrcExtent, class DestElementType,
           std::ptrdiff_t DestExtent>
 void copy(span<SrcElementType, SrcExtent> src, span<DestElementType, DestExtent> dest)
@@ -51,6 +48,7 @@ void copy(span<SrcElementType, SrcExtent> src, span<DestElementType, DestExtent>
                   "Source range is longer than target range");
 
     Expects(dest.size() >= src.size());
+    GSL_SUPPRESS(stl.1) // NO-FORMAT: attribute
     std::copy_n(src.data(), src.size(), dest.data());
 }
 
diff --git a/include/gsl/gsl_assert b/include/gsl/gsl_assert
index 70a6eba..321bf20 100644
--- a/include/gsl/gsl_assert
+++ b/include/gsl/gsl_assert
@@ -21,6 +21,20 @@
 #include <stdexcept> // for logic_error
 
 //
+// make suppress attributes parse for some compilers
+// Hopefully temporary until suppresion stardization occurs
+//
+#if defined (_MSC_VER)
+#define GSL_SUPPRESS(x) [[gsl::suppress(x)]]
+#else
+#if defined(__clang__)
+#define GSL_SUPPRESS(x) [[gsl::suppress("x")]]
+#else
+#define GSL_SUPPRESS(x)
+#endif // __clang__
+#endif // _MSC_VER
+
+//
 // Temporary until MSVC STL supports no-exceptions mode.
 // Currently terminate is a no-op in this mode, so we add termination behavior back
 //
@@ -85,6 +99,7 @@ namespace details
 
     typedef void  (__cdecl *terminate_handler)();
     
+    GSL_SUPPRESS(f.6) // NO-FORMAT: attribute
     [[noreturn]] inline void __cdecl default_terminate_handler()
     {
         __fastfail(RANGE_CHECKS_FAILURE);
@@ -110,11 +125,7 @@ namespace details
 #if defined(GSL_TERMINATE_ON_CONTRACT_VIOLATION)
 
     template <typename Exception>
-#if defined(__clang__) || defined(__GNUC__)
-#else
-    [[gsl::suppress(f.6)]]
-#endif
-    [[noreturn]] void throw_exception(Exception&&)
+    [[noreturn]] void throw_exception(Exception&&) noexcept
     {
         gsl::details::terminate();
     }
diff --git a/include/gsl/gsl_byte b/include/gsl/gsl_byte
index 6b770fd..bc18886 100644
--- a/include/gsl/gsl_byte
+++ b/include/gsl/gsl_byte
@@ -17,14 +17,28 @@
 #ifndef GSL_BYTE_H
 #define GSL_BYTE_H
 
+//
+// make suppress attributes work for some compilers
+// Hopefully temporary until suppresion standardization occurs
+//
+#if defined(_MSC_VER)
+#define GSL_SUPPRESS(x) [[gsl::suppress(x)]]
+#else
+#if defined(__clang__)
+#define GSL_SUPPRESS(x) [[gsl::suppress("x")]]
+#else
+#define GSL_SUPPRESS(x)
+#endif // __clang__
+#endif // _MSC_VER
+
 #include <type_traits>
 
 #ifdef _MSC_VER
 
 #pragma warning(push)
 
-// don't warn about function style casts in byte related operators
-#pragma warning(disable : 26493)
+// Turn MSVC /analyze rules that generate too much noise. TODO: fix in the tool.
+#pragma warning(disable : 26493) // don't use c-style casts // TODO: MSVC suppression in templates does not always work
 
 #ifndef GSL_USE_STD_BYTE
 // this tests if we are under MSVC and the standard lib has std::byte and it is enabled
@@ -57,12 +71,12 @@
 
 #define GSL_USE_STD_BYTE 0
 
-#endif //defined(__cplusplus) && (__cplusplus >= 201703L)
+#endif //defined(__cplusplus) && (__cplusplus >= 201703L) &&
        //   (defined(__cpp_lib_byte) && (__cpp_lib_byte >= 201603)  ||
        //    defined(_LIBCPP_VERSION) && (_LIBCPP_VERSION >= 5000))
 #endif // GSL_USE_STD_BYTE
 
-#endif           // _MSC_VER
+#endif // _MSC_VER
 
 // Use __may_alias__ attribute on gcc and clang
 #if defined __clang__ || (__GNUC__ > 5)
@@ -75,7 +89,6 @@ namespace gsl
 {
 #if GSL_USE_STD_BYTE
 
-
 using std::byte;
 using std::to_integer;
 
@@ -160,6 +173,8 @@ constexpr byte to_byte_impl(T t) noexcept
     return static_cast<byte>(t);
 }
 template <>
+// NOTE: need suppression since c++14 does not allow "return {t}"
+// GSL_SUPPRESS(type.4) // NO-FORMAT: attribute // TODO: suppression does not work
 constexpr byte to_byte_impl<true, unsigned char>(unsigned char t) noexcept
 {
     return byte(t);
diff --git a/include/gsl/gsl_util b/include/gsl/gsl_util
index ee61711..542bbaa 100644
--- a/include/gsl/gsl_util
+++ b/include/gsl/gsl_util
@@ -34,8 +34,8 @@
 #if _MSC_VER < 1910
 #pragma push_macro("constexpr")
 #define constexpr /*constexpr*/
-#endif                          // _MSC_VER < 1910
-#endif                          // _MSC_VER
+#endif            // _MSC_VER < 1910
+#endif            // _MSC_VER
 
 namespace gsl
 {
@@ -62,6 +62,7 @@ public:
     final_action& operator=(const final_action&) = delete;
     final_action& operator=(final_action&&) = delete;
 
+    GSL_SUPPRESS(f.6) // NO-FORMAT: attribute // terminate if throws
     ~final_action() noexcept
     {
         if (invoke_) f_();
@@ -69,12 +70,11 @@ public:
 
 private:
     F f_;
-    bool invoke_ {true};
+    bool invoke_{true};
 };
 
 // finally() - convenience function to generate a final_action
 template <class F>
-
 final_action<F> finally(const F& f) noexcept
 {
     return final_action<F>(f);
@@ -88,10 +88,7 @@ final_action<F> finally(F&& f) noexcept
 
 // narrow_cast(): a searchable way to do narrowing casts of values
 template <class T, class U>
-#if defined(__clang__) || defined(__GNUC__)
-#else
-[[gsl::suppress(type.1)]]
-#endif
+GSL_SUPPRESS(type.1) // NO-FORMAT: attribute
 constexpr T narrow_cast(U&& u) noexcept
 {
     return static_cast<T>(std::forward<U>(u));
@@ -108,15 +105,13 @@ namespace details
         : public std::integral_constant<bool, std::is_signed<T>::value == std::is_signed<U>::value>
     {
     };
-}
+} // namespace details
 
 // narrow() : a checked version of narrow_cast() that throws if the cast changed the value
 template <class T, class U>
-#if defined(__clang__) || defined(__GNUC__)
-#else
-[[gsl::suppress(type.1)]]
-#endif
-T narrow(U u)
+GSL_SUPPRESS(type.1) // NO-FORMAT: attribute
+GSL_SUPPRESS(f.6) // NO-FORMAT: attribute // TODO: MSVC /analyze does not recognise noexcept(false)
+T narrow(U u) noexcept(false)
 {
     T t = narrow_cast<T>(u);
     if (static_cast<U>(t) != u) gsl::details::throw_exception(narrowing_error());
@@ -129,29 +124,26 @@ T narrow(U u)
 // at() - Bounds-checked way of accessing builtin arrays, std::array, std::vector
 //
 template <class T, std::size_t N>
-#if defined(__clang__) || defined(__GNUC__)
-#else
-[[gsl::suppress(type.1,bounds.2,bounds.4)]]
-#endif
+GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
+GSL_SUPPRESS(bounds.2) // NO-FORMAT: attribute
 constexpr T& at(T (&arr)[N], const index i)
 {
     Expects(i >= 0 && i < narrow_cast<index>(N));
-    return arr[static_cast<std::size_t>(i)];
+    return arr[narrow_cast<std::size_t>(i)];
 }
 
 template <class Cont>
-#if defined(__clang__) || defined(__GNUC__)
-#else
-[[gsl::suppress(type.1,bounds.4)]]
-#endif
+GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
+GSL_SUPPRESS(bounds.2) // NO-FORMAT: attribute
 constexpr auto at(Cont& cont, const index i) -> decltype(cont[cont.size()])
 {
     Expects(i >= 0 && i < narrow_cast<index>(cont.size()));
     using size_type = decltype(cont.size());
-    return cont[static_cast<size_type>(i)];
+    return cont[narrow_cast<size_type>(i)];
 }
 
 template <class T>
+GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
 constexpr T at(const std::initializer_list<T> cont, const index i)
 {
     Expects(i >= 0 && i < narrow_cast<index>(cont.size()));
diff --git a/include/gsl/multi_span b/include/gsl/multi_span
index 9862d0d..a7c96ce 100644
--- a/include/gsl/multi_span
+++ b/include/gsl/multi_span
@@ -44,6 +44,12 @@
 #pragma warning(disable : 4127) // conditional expression is constant
 #pragma warning(disable : 4702) // unreachable code
 
+// Turn MSVC /analyze rules that generate too much noise. TODO: fix in the tool.
+#pragma warning(disable : 26495) // uninitalized member when constructor calls constructor
+#pragma warning(disable : 26473) // in some instantiations we cast to the same type
+#pragma warning(disable : 26490) // TODO: bug in parser - attributes and templates
+#pragma warning(disable : 26465) // TODO: bug - suppression does not work on template functions
+
 #if _MSC_VER < 1910
 #pragma push_macro("constexpr")
 #define constexpr /*constexpr*/
@@ -52,9 +58,9 @@
 #endif                          // _MSC_VER
 
 // GCC 7 does not like the signed unsigned missmatch (size_t ptrdiff_t)
-// While there is a conversion from signed to unsigned, it happens at 
-// compiletime, so the compiler wouldn't have to warn indiscriminently, but 
-// could check if the source value actually doesn't fit into the target type 
+// While there is a conversion from signed to unsigned, it happens at
+// compiletime, so the compiler wouldn't have to warn indiscriminently, but
+// could check if the source value actually doesn't fit into the target type
 // and only warn in those cases.
 #if __GNUC__ > 6
 #pragma GCC diagnostic push
@@ -86,7 +92,7 @@ namespace details
                                         std::is_integral<T>::value && are_integral<Ts...>::value>
     {
     };
-}
+} // namespace details
 
 template <std::size_t Rank>
 class multi_span_index final
@@ -107,20 +113,23 @@ public:
 
     constexpr multi_span_index(const value_type (&values)[Rank]) noexcept
     {
+        GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
+        GSL_SUPPRESS(bounds.3) // NO-FORMAT: attribute
         std::copy(values, values + Rank, elems);
     }
 
     template <typename... Ts, typename = std::enable_if_t<(sizeof...(Ts) == Rank) &&
                                                           details::are_integral<Ts...>::value>>
     constexpr multi_span_index(Ts... ds) noexcept : elems{narrow_cast<value_type>(ds)...}
-    {
-    }
+    {}
 
     constexpr multi_span_index(const multi_span_index& other) noexcept = default;
 
     constexpr multi_span_index& operator=(const multi_span_index& rhs) noexcept = default;
 
     // Preconditions: component_idx < rank
+    GSL_SUPPRESS(bounds.2) // NO-FORMAT: attribute
+    GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
     constexpr reference operator[](std::size_t component_idx)
     {
         Expects(component_idx < Rank); // Component index must be less than rank
@@ -128,18 +137,25 @@ public:
     }
 
     // Preconditions: component_idx < rank
-    constexpr const_reference operator[](std::size_t component_idx) const
+    GSL_SUPPRESS(bounds.2) // NO-FORMAT: attribute
+    GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
+    constexpr const_reference operator[](std::size_t component_idx) const 
     {
         Expects(component_idx < Rank); // Component index must be less than rank
         return elems[component_idx];
     }
 
+    GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
+    GSL_SUPPRESS(bounds.3) // NO-FORMAT: attribute
     constexpr bool operator==(const multi_span_index& rhs) const
     {
         return std::equal(elems, elems + rank, rhs.elems);
     }
 
-    constexpr bool operator!=(const multi_span_index& rhs) const { return !(*this == rhs); }
+    constexpr bool operator!=(const multi_span_index& rhs) const
+    {
+        return !(*this == rhs);
+    }
 
     constexpr multi_span_index operator+() const noexcept { return *this; }
 
@@ -166,12 +182,17 @@ public:
 
     constexpr multi_span_index& operator+=(const multi_span_index& rhs)
     {
-        std::transform(elems, elems + rank, rhs.elems, elems, std::plus<value_type>{});
+        GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
+        GSL_SUPPRESS(bounds.3) // NO-FORMAT: attribute
+        std::transform(elems, elems + rank, rhs.elems, elems,
+                       std::plus<value_type>{});
         return *this;
     }
 
     constexpr multi_span_index& operator-=(const multi_span_index& rhs)
     {
+        GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
+        GSL_SUPPRESS(bounds.3) // NO-FORMAT: attribute
         std::transform(elems, elems + rank, rhs.elems, elems, std::minus<value_type>{});
         return *this;
     }
@@ -197,6 +218,8 @@ public:
 
     constexpr multi_span_index& operator*=(value_type v)
     {
+        GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
+        GSL_SUPPRESS(bounds.3) // NO-FORMAT: attribute
         std::transform(elems, elems + rank, elems,
                        [v](value_type x) { return std::multiplies<value_type>{}(x, v); });
         return *this;
@@ -204,6 +227,8 @@ public:
 
     constexpr multi_span_index& operator/=(value_type v)
     {
+        GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
+        GSL_SUPPRESS(bounds.3) // NO-FORMAT: attribute
         std::transform(elems, elems + rank, elems,
                        [v](value_type x) { return std::divides<value_type>{}(x, v); });
         return *this;
@@ -291,16 +316,14 @@ namespace details
         // TODO : following signature is for work around VS bug
         template <typename OtherRange>
         BoundsRanges(const OtherRange&, bool /* firstLevel */)
-        {
-        }
+        {}
 
         BoundsRanges(const std::ptrdiff_t* const) {}
-        BoundsRanges() = default;
+        BoundsRanges() noexcept = default;
 
         template <typename T, std::size_t Dim>
         void serialize(T&) const
-        {
-        }
+        {}
 
         template <typename T, std::size_t Dim>
         size_type linearize(const T&) const
@@ -335,21 +358,22 @@ namespace details
         size_type m_bound;
 
     public:
+        GSL_SUPPRESS(f.23) // NO-FORMAT: attribute // this pointer type is cannot be assigned nullptr - issue in not_null
+        GSL_SUPPRESS(bounds.1)  // NO-FORMAT: attribute
         BoundsRanges(const std::ptrdiff_t* const arr)
             : Base(arr + 1), m_bound(*arr * this->Base::totalSize())
         {
             Expects(0 <= *arr);
         }
 
-        BoundsRanges() : m_bound(0) {}
+        BoundsRanges() noexcept : m_bound(0) {}
 
         template <std::ptrdiff_t OtherRange, std::ptrdiff_t... RestOtherRanges>
         BoundsRanges(const BoundsRanges<OtherRange, RestOtherRanges...>& other,
                      bool /* firstLevel */ = true)
             : Base(static_cast<const BoundsRanges<RestOtherRanges...>&>(other), false)
             , m_bound(other.totalSize())
-        {
-        }
+        {}
 
         template <typename T, std::size_t Dim = 0>
         void serialize(T& arr) const
@@ -359,6 +383,7 @@ namespace details
         }
 
         template <typename T, std::size_t Dim = 0>
+        GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
         size_type linearize(const T& arr) const
         {
             const size_type index = this->Base::totalSize() * arr[Dim];
@@ -375,9 +400,17 @@ namespace details
             return cur < m_bound ? cur + last : -1;
         }
 
-        size_type totalSize() const noexcept { return m_bound; }
+        GSL_SUPPRESS(c.128) // NO-FORMAT: attribute // no pointers to BoundsRanges should be ever used
+        size_type totalSize() const noexcept
+        {
+            return m_bound;
+        }
 
-        size_type elementNum() const noexcept { return totalSize() / this->Base::totalSize(); }
+        GSL_SUPPRESS(c.128) // NO-FORMAT: attribute // no pointers to BoundsRanges should be ever used
+        size_type elementNum() const noexcept
+        {
+            return totalSize() / this->Base::totalSize();
+        }
 
         size_type elementNum(std::size_t dim) const noexcept
         {
@@ -413,6 +446,7 @@ namespace details
                      bool firstLevel = true)
             : Base(static_cast<const BoundsRanges<RestOtherRanges...>&>(other), false)
         {
+            GSL_SUPPRESS(type.4) // NO-FORMAT: attribute // TODO: false positive
             (void) firstLevel;
         }
 
@@ -426,7 +460,10 @@ namespace details
         template <typename T, std::size_t Dim = 0>
         size_type linearize(const T& arr) const
         {
+            GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
             Expects(arr[Dim] >= 0 && arr[Dim] < CurrentRange); // Index is out of range
+
+            GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
             return this->Base::totalSize() * arr[Dim] +
                    this->Base::template linearize<T, Dim + 1>(arr);
         }
@@ -440,10 +477,19 @@ namespace details
             return this->Base::totalSize() * arr[Dim] + last;
         }
 
-        size_type totalSize() const noexcept { return CurrentRange * this->Base::totalSize(); }
+        GSL_SUPPRESS(c.128) // NO-FORMAT: attribute // no pointers to BoundsRanges should be ever used
+        size_type totalSize() const noexcept
+        {
+            return CurrentRange * this->Base::totalSize();
+        }
 
-        size_type elementNum() const noexcept { return CurrentRange; }
+        GSL_SUPPRESS(c.128) // NO-FORMAT: attribute // no pointers to BoundsRanges should be ever used
+        size_type elementNum() const noexcept
+        {
+            return CurrentRange;
+        }
 
+        GSL_SUPPRESS(c.128) // NO-FORMAT: attribute // no pointers to BoundsRanges should be ever used
         size_type elementNum(std::size_t dim) const noexcept
         {
             if (dim > 0)
@@ -505,12 +551,14 @@ namespace details
     constexpr Ret shift_left(const multi_span_index<Rank>& other) noexcept
     {
         Ret ret{};
-        for (std::size_t i = 0; i < Rank - 1; ++i) {
-            ret[i] = other[i + 1];
+        for (std::size_t i = 0; i < Rank - 1; ++i)
+        {
+            GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
+                ret[i] = other[i + 1];
         }
         return ret;
     }
-}
+} // namespace details
 
 template <typename IndexType>
 class bounds_iterator;
@@ -528,7 +576,7 @@ class static_bounds<FirstRange, RestRanges...>
     using MyRanges = details::BoundsRanges<FirstRange, RestRanges...>;
 
     MyRanges m_ranges;
-    constexpr static_bounds(const MyRanges& range) : m_ranges(range) {}
+    constexpr static_bounds(const MyRanges& range) noexcept : m_ranges(range) {}
 
     template <std::ptrdiff_t... OtherRanges>
     friend class static_bounds;
@@ -547,7 +595,8 @@ public:
     using sliced_type = static_bounds<RestRanges...>;
     using mapping_type = contiguous_mapping_tag;
 
-    constexpr static_bounds(const static_bounds&) = default;
+    constexpr static_bounds(const static_bounds&) noexcept = default;
+    constexpr static_bounds() /*noexcept*/ = default;
 
     template <typename SourceType, typename TargetType, std::size_t Rank>
     struct BoundsRangeConvertible2;
@@ -605,8 +654,7 @@ public:
                 MyRanges::DynamicNum > 0 || other.m_ranges.totalSize() >= m_ranges.totalSize());
     }
 
-    constexpr static_bounds(std::initializer_list<size_type> il)
-        : m_ranges(il.begin())
+    constexpr static_bounds(std::initializer_list<size_type> il) : m_ranges(il.begin())
     {
         // Size of the initializer list must match the rank of the array
         Expects((MyRanges::DynamicNum == 0 && il.size() == 1 && *il.begin() == static_size) ||
@@ -615,8 +663,6 @@ public:
         Expects(m_ranges.totalSize() <= PTRDIFF_MAX);
     }
 
-    constexpr static_bounds() = default;
-
     constexpr sliced_type slice() const noexcept
     {
         return sliced_type{static_cast<const details::BoundsRanges<RestRanges...>&>(m_ranges)};
@@ -690,8 +736,7 @@ public:
 };
 
 template <std::size_t Rank>
-class strided_bounds
-{
+class strided_bounds {
     template <std::size_t OtherRank>
     friend class strided_bounds;
 
@@ -717,53 +762,53 @@ public:
 
     constexpr strided_bounds(const value_type (&values)[rank], index_type strides)
         : m_extents(values), m_strides(std::move(strides))
-    {
-    }
+    {}
 
     constexpr strided_bounds(const index_type& extents, const index_type& strides) noexcept
-        : m_extents(extents),
-          m_strides(strides)
+        : m_extents(extents), m_strides(strides)
     {
     }
 
     constexpr index_type strides() const noexcept { return m_strides; }
 
+    GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
     constexpr size_type total_size() const noexcept
     {
         size_type ret = 0;
-        for (std::size_t i = 0; i < rank; ++i) {
-            ret += (m_extents[i] - 1) * m_strides[i];
-        }
+        for (std::size_t i = 0; i < rank; ++i) { ret += (m_extents[i] - 1) * m_strides[i]; }
         return ret + 1;
     }
 
+    GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
     constexpr size_type size() const noexcept
     {
         size_type ret = 1;
-        for (std::size_t i = 0; i < rank; ++i) {
-            ret *= m_extents[i];
-        }
+        for (std::size_t i = 0; i < rank; ++i) { ret *= m_extents[i]; }
         return ret;
     }
 
     constexpr bool contains(const index_type& idx) const noexcept
     {
-        for (std::size_t i = 0; i < rank; ++i) {
+        for (std::size_t i = 0; i < rank; ++i)
+        {
             if (idx[i] < 0 || idx[i] >= m_extents[i]) return false;
         }
         return true;
     }
 
+    GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
     constexpr size_type linearize(const index_type& idx) const
     {
         size_type ret = 0;
-        for (std::size_t i = 0; i < rank; i++) {
+        for (std::size_t i = 0; i < rank; i++)
+        {
             Expects(idx[i] < m_extents[i]); // index is out of bounds of the array
             ret += idx[i] * m_strides[i];
         }
         return ret;
     }
 
+    GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
     constexpr size_type stride() const noexcept { return m_strides[0]; }
 
     template <bool Enabled = (rank > 1), typename Ret = std::enable_if_t<Enabled, sliced_type>>
@@ -773,6 +818,8 @@ public:
     }
 
     template <std::size_t Dim = 0>
+
+    GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
     constexpr size_type extent() const noexcept
     {
         static_assert(Dim < Rank,
@@ -781,15 +828,10 @@ public:
     }
 
     constexpr index_type index_bounds() const noexcept { return m_extents; }
-    constexpr const_iterator begin() const noexcept
-    {
-        return const_iterator{*this, index_type{}};
-    }
 
-    constexpr const_iterator end() const noexcept
-    {
-        return const_iterator{*this, index_bounds()};
-    }
+    constexpr const_iterator begin() const noexcept { return const_iterator{*this, index_type{}}; }
+
+    constexpr const_iterator end() const noexcept { return const_iterator{*this, index_bounds()}; }
 
 private:
     index_type m_extents;
@@ -823,8 +865,7 @@ public:
     using index_size_type = typename IndexType::value_type;
     template <typename Bounds>
     explicit bounds_iterator(const Bounds& bnd, value_type curr) noexcept
-        : boundary_(bnd.index_bounds()),
-          curr_(std::move(curr))
+        : boundary_(bnd.index_bounds()), curr_(std::move(curr))
     {
         static_assert(is_bounds<Bounds>::value, "Bounds type must be provided");
     }
@@ -833,10 +874,15 @@ public:
 
     constexpr pointer operator->() const noexcept { return &curr_; }
 
+    GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
+    GSL_SUPPRESS(bounds.2) // NO-FORMAT: attribute
     constexpr bounds_iterator& operator++() noexcept
+
     {
-        for (std::size_t i = rank; i-- > 0;) {
-            if (curr_[i] < boundary_[i] - 1) {
+        for (std::size_t i = rank; i-- > 0;)
+        {
+            if (curr_[i] < boundary_[i] - 1)
+            {
                 curr_[i]++;
                 return *this;
             }
@@ -854,17 +900,19 @@ public:
         return ret;
     }
 
+    GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
     constexpr bounds_iterator& operator--()
     {
-        if (!less(curr_, boundary_)) {
+        if (!less(curr_, boundary_))
+        {
             // if at the past-the-end, set to last element
-            for (std::size_t i = 0; i < rank; ++i) {
-                curr_[i] = boundary_[i] - 1;
-            }
+            for (std::size_t i = 0; i < rank; ++i) { curr_[i] = boundary_[i] - 1; }
             return *this;
         }
-        for (std::size_t i = rank; i-- > 0;) {
-            if (curr_[i] >= 1) {
+        for (std::size_t i = rank; i-- > 0;)
+        {
+            if (curr_[i] >= 1)
+            {
                 curr_[i]--;
                 return *this;
             }
@@ -889,15 +937,15 @@ public:
         return ret += n;
     }
 
+    GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
     constexpr bounds_iterator& operator+=(difference_type n)
     {
         auto linear_idx = linearize(curr_) + n;
         std::remove_const_t<value_type> stride = 0;
         stride[rank - 1] = 1;
-        for (std::size_t i = rank - 1; i-- > 0;) {
-            stride[i] = stride[i + 1] * boundary_[i + 1];
-        }
-        for (std::size_t i = 0; i < rank; ++i) {
+        for (std::size_t i = rank - 1; i-- > 0;) { stride[i] = stride[i + 1] * boundary_[i + 1]; }
+        for (std::size_t i = 0; i < rank; ++i)
+        {
             curr_[i] = linear_idx / stride[i];
             linear_idx = linear_idx % stride[i];
         }
@@ -926,27 +974,19 @@ public:
         return curr_ == rhs.curr_;
     }
 
-    constexpr bool operator!=(const bounds_iterator& rhs) const noexcept
-    {
-        return !(*this == rhs);
-    }
+
+    constexpr bool operator!=(const bounds_iterator& rhs) const noexcept { return !(*this == rhs); }
 
     constexpr bool operator<(const bounds_iterator& rhs) const noexcept
     {
         return less(curr_, rhs.curr_);
     }
 
-    constexpr bool operator<=(const bounds_iterator& rhs) const noexcept
-    {
-        return !(rhs < *this);
-    }
+    constexpr bool operator<=(const bounds_iterator& rhs) const noexcept { return !(rhs < *this); }
 
     constexpr bool operator>(const bounds_iterator& rhs) const noexcept { return rhs < *this; }
 
-    constexpr bool operator>=(const bounds_iterator& rhs) const noexcept
-    {
-        return !(rhs > *this);
-    }
+    constexpr bool operator>=(const bounds_iterator& rhs) const noexcept { return !(rhs > *this); }
 
     void swap(bounds_iterator& rhs) noexcept
     {
@@ -955,30 +995,37 @@ public:
     }
 
 private:
+
+    GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
     constexpr bool less(index_type& one, index_type& other) const noexcept
     {
-        for (std::size_t i = 0; i < rank; ++i) {
+        for (std::size_t i = 0; i < rank; ++i)
+        {
             if (one[i] < other[i]) return true;
         }
         return false;
     }
 
+    GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
     constexpr index_size_type linearize(const value_type& idx) const noexcept
     {
         // TODO: Smarter impl.
         // Check if past-the-end
         index_size_type multiplier = 1;
         index_size_type res = 0;
-        if (!less(idx, boundary_)) {
+        if (!less(idx, boundary_))
+        {
             res = 1;
-            for (std::size_t i = rank; i-- > 0;) {
+            for (std::size_t i = rank; i-- > 0;)
+            {
                 res += (idx[i] - 1) * multiplier;
                 multiplier *= boundary_[i];
             }
         }
         else
         {
-            for (std::size_t i = rank; i-- > 0;) {
+            for (std::size_t i = rank; i-- > 0;)
+            {
                 res += idx[i] * multiplier;
                 multiplier *= boundary_[i];
             }
@@ -1019,7 +1066,10 @@ namespace details
         typename Bounds::size_type stride[Bounds::rank] = {};
 
         stride[Bounds::rank - 1] = 1;
-        for (std::size_t i = 1; i < Bounds::rank; ++i) {
+        for (std::size_t i = 1; i < Bounds::rank; ++i)
+        {
+            GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
+            GSL_SUPPRESS(bounds.2) // NO-FORMAT: attribute
             stride[Bounds::rank - i - 1] = stride[Bounds::rank - i] * extents[Bounds::rank - i];
         }
         return {stride};
@@ -1175,7 +1225,7 @@ namespace details
     struct is_multi_span : is_multi_span_oracle<std::remove_cv_t<T>>
     {
     };
-}
+} // namespace details
 
 template <typename ValueType, std::ptrdiff_t FirstDimension, std::ptrdiff_t... RestDimensions>
 class multi_span
@@ -1211,7 +1261,9 @@ private:
 
 public:
     // default constructor - same as constructing from nullptr_t
-    constexpr multi_span() noexcept : multi_span(nullptr, bounds_type{})
+    GSL_SUPPRESS(type.6) // NO-FORMAT: attribute // TODO: false positive
+    constexpr multi_span() noexcept
+        : multi_span(nullptr, bounds_type{})
     {
         static_assert(bounds_type::dynamic_rank != 0 ||
                           (bounds_type::dynamic_rank == 0 && bounds_type::static_size == 0),
@@ -1220,7 +1272,9 @@ public:
     }
 
     // construct from nullptr - get an empty multi_span
-    constexpr multi_span(std::nullptr_t) noexcept : multi_span(nullptr, bounds_type{})
+    GSL_SUPPRESS(type.6) // NO-FORMAT: attribute // TODO: false positive
+    constexpr multi_span(std::nullptr_t) noexcept
+        : multi_span(nullptr, bounds_type{})
     {
         static_assert(bounds_type::dynamic_rank != 0 ||
                           (bounds_type::dynamic_rank == 0 && bounds_type::static_size == 0),
@@ -1230,8 +1284,9 @@ public:
 
     // construct from nullptr with size of 0 (helps with template function calls)
     template <class IntType, typename = std::enable_if_t<std::is_integral<IntType>::value>>
-    constexpr multi_span(std::nullptr_t, IntType size)
-        : multi_span(nullptr, bounds_type{})
+
+    // GSL_SUPPRESS(type.6) // NO-FORMAT: attribute // TODO: false positive // TODO: parser bug
+    constexpr multi_span(std::nullptr_t, IntType size) : multi_span(nullptr, bounds_type{})
     {
         static_assert(bounds_type::dynamic_rank != 0 ||
                           (bounds_type::dynamic_rank == 0 && bounds_type::static_size == 0),
@@ -1241,7 +1296,10 @@ public:
     }
 
     // construct from a single element
-    constexpr multi_span(reference data) noexcept : multi_span(&data, bounds_type{1})
+
+    GSL_SUPPRESS(type.6) // NO-FORMAT: attribute // TODO: false positive
+    constexpr multi_span(reference data) noexcept
+        : multi_span(&data, bounds_type{1})
     {
         static_assert(bounds_type::dynamic_rank > 0 || bounds_type::static_size == 0 ||
                           bounds_type::static_size == 1,
@@ -1253,14 +1311,14 @@ public:
     constexpr multi_span(value_type&&) = delete;
 
     // construct from pointer + length
+    GSL_SUPPRESS(type.6) // NO-FORMAT: attribute // TODO: false positive
     constexpr multi_span(pointer ptr, size_type size)
         : multi_span(ptr, bounds_type{size})
-    {
-    }
+    {}
 
     // construct from pointer + length - multidimensional
-    constexpr multi_span(pointer data, bounds_type bounds) : data_(data),
-                                                                          bounds_(std::move(bounds))
+    constexpr multi_span(pointer data, bounds_type bounds)
+        : data_(data), bounds_(std::move(bounds))
     {
         Expects((bounds_.size() > 0 && data != nullptr) || bounds_.size() == 0);
     }
@@ -1314,8 +1372,9 @@ public:
     constexpr multi_span(const std::array<T, N>& arr)
         : multi_span(arr.data(), bounds_type{static_bounds<N>{}})
     {
-        static_assert(std::is_convertible<T(*)[], typename std::remove_const_t<value_type>(*)[]>::value,
-                      "Cannot convert from source type to target multi_span type.");
+        static_assert(
+            std::is_convertible<T(*)[], typename std::remove_const_t<value_type>(*)[]>::value,
+            "Cannot convert from source type to target multi_span type.");
         static_assert(std::is_convertible<static_bounds<N>, bounds_type>::value,
                       "You cannot construct a multi_span from a std::array of smaller size.");
     }
@@ -1337,8 +1396,7 @@ public:
     constexpr multi_span(Cont& cont)
         : multi_span(static_cast<pointer>(cont.data()),
                      details::newBoundsHelper<bounds_type>(narrow_cast<size_type>(cont.size())))
-    {
-    }
+    {}
 
     // prevent constructing from temporary containers
     template <typename Cont, typename DataType = typename Cont::value_type,
@@ -1356,10 +1414,8 @@ public:
               typename = std::enable_if_t<std::is_convertible<OtherValueType, ValueType>::value &&
                                           std::is_convertible<OtherBounds, bounds_type>::value>>
     constexpr multi_span(multi_span<OtherValueType, OtherDimensions...> other)
-        : data_(other.data_),
-          bounds_(other.bounds_)
-    {
-    }
+        : data_(other.data_), bounds_(other.bounds_)
+    {}
 
     // trivial copy and move
     constexpr multi_span(const multi_span&) = default;
@@ -1371,6 +1427,7 @@ public:
 
     // first() - extract the first Count elements into a new multi_span
     template <std::ptrdiff_t Count>
+
     constexpr multi_span<ValueType, Count> first() const
     {
         static_assert(Count >= 0, "Count must be >= 0.");
@@ -1427,8 +1484,8 @@ public:
 
     // subspan() - create a subview of count elements starting at offset
     // supplying dynamic_range for count will consume all available elements from offset
-    constexpr multi_span<ValueType, dynamic_range>
-    subspan(size_type offset, size_type count = dynamic_range) const
+    constexpr multi_span<ValueType, dynamic_range> subspan(size_type offset,
+                                                           size_type count = dynamic_range) const
     {
         Expects((offset >= 0 && offset <= this->size()) &&
                 (count == dynamic_range || (count <= this->size() - offset)));
@@ -1439,7 +1496,7 @@ public:
     constexpr strided_span<ValueType, Rank> section(index_type origin,
                                                     index_type extents) const
     {
-        size_type size = this->bounds().total_size() - this->bounds().linearize(origin);
+        const size_type size = this->bounds().total_size() - this->bounds().linearize(origin);
         return {&this->operator[](origin), size,
                 strided_bounds<Rank>{extents, details::make_stride(bounds())}};
     }
@@ -1490,17 +1547,20 @@ public:
     template <typename FirstIndex, typename... OtherIndices>
     constexpr reference operator()(FirstIndex firstIndex, OtherIndices... indices)
     {
-        index_type idx = {narrow_cast<std::ptrdiff_t>(firstIndex),
-                          narrow_cast<std::ptrdiff_t>(indices)...};
+        const index_type idx = {narrow_cast<std::ptrdiff_t>(firstIndex),
+                                narrow_cast<std::ptrdiff_t>(indices)...};
         return this->operator[](idx);
     }
 
+    GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
     constexpr reference operator[](const index_type& idx) const
     {
         return data_[bounds_.linearize(idx)];
     }
 
     template <bool Enabled = (Rank > 1), typename Ret = std::enable_if_t<Enabled, sliced_type>>
+
+    GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
     constexpr Ret operator[](size_type idx) const
     {
         Expects(idx >= 0 && idx < bounds_.size()); // index is out of bounds of the array
@@ -1515,6 +1575,7 @@ public:
 
     constexpr iterator end() const noexcept { return iterator{this, false}; }
 
+    GSL_SUPPRESS(type.1) // NO-FORMAT: attribute
     constexpr const_iterator cbegin() const noexcept
     {
         return const_iterator{reinterpret_cast<const const_span*>(this), true};
@@ -1540,56 +1601,51 @@ public:
     }
 
     template <typename OtherValueType, std::ptrdiff_t... OtherDimensions,
-              typename = std::enable_if_t<std::is_same<
-                  std::remove_cv_t<value_type>, std::remove_cv_t<OtherValueType>>::value>>
-    constexpr bool
-    operator==(const multi_span<OtherValueType, OtherDimensions...>& other) const noexcept
+              typename = std::enable_if_t<std::is_same<std::remove_cv_t<value_type>,
+                                                       std::remove_cv_t<OtherValueType>>::value>>
+    constexpr bool operator==(const multi_span<OtherValueType, OtherDimensions...>& other) const
     {
         return bounds_.size() == other.bounds_.size() &&
                (data_ == other.data_ || std::equal(this->begin(), this->end(), other.begin()));
     }
 
     template <typename OtherValueType, std::ptrdiff_t... OtherDimensions,
-              typename = std::enable_if_t<std::is_same<
-                  std::remove_cv_t<value_type>, std::remove_cv_t<OtherValueType>>::value>>
-    constexpr bool
-    operator!=(const multi_span<OtherValueType, OtherDimensions...>& other) const noexcept
+              typename = std::enable_if_t<std::is_same<std::remove_cv_t<value_type>,
+                                                       std::remove_cv_t<OtherValueType>>::value>>
+    constexpr bool operator!=(const multi_span<OtherValueType, OtherDimensions...>& other) const
     {
         return !(*this == other);
     }
 
     template <typename OtherValueType, std::ptrdiff_t... OtherDimensions,
-              typename = std::enable_if_t<std::is_same<
-                  std::remove_cv_t<value_type>, std::remove_cv_t<OtherValueType>>::value>>
-    constexpr bool
-    operator<(const multi_span<OtherValueType, OtherDimensions...>& other) const noexcept
+              typename = std::enable_if_t<std::is_same<std::remove_cv_t<value_type>,
+                                                       std::remove_cv_t<OtherValueType>>::value>>
+    constexpr bool operator<(const multi_span<OtherValueType, OtherDimensions...>& other) const
     {
         return std::lexicographical_compare(this->begin(), this->end(), other.begin(), other.end());
     }
 
     template <typename OtherValueType, std::ptrdiff_t... OtherDimensions,
-              typename = std::enable_if_t<std::is_same<
-                  std::remove_cv_t<value_type>, std::remove_cv_t<OtherValueType>>::value>>
-    constexpr bool
-    operator<=(const multi_span<OtherValueType, OtherDimensions...>& other) const noexcept
+              typename = std::enable_if_t<std::is_same<std::remove_cv_t<value_type>,
+                                                       std::remove_cv_t<OtherValueType>>::value>>
+    constexpr bool operator<=(const multi_span<OtherValueType, OtherDimensions...>& other) const
     {
         return !(other < *this);
     }
 
     template <typename OtherValueType, std::ptrdiff_t... OtherDimensions,
-              typename = std::enable_if_t<std::is_same<
-                  std::remove_cv_t<value_type>, std::remove_cv_t<OtherValueType>>::value>>
-    constexpr bool
-    operator>(const multi_span<OtherValueType, OtherDimensions...>& other) const noexcept
+              typename = std::enable_if_t<std::is_same<std::remove_cv_t<value_type>,
+                                                       std::remove_cv_t<OtherValueType>>::value>>
+    constexpr bool operator>(const multi_span<OtherValueType, OtherDimensions...>& other) const
+        noexcept
     {
         return (other < *this);
     }
 
     template <typename OtherValueType, std::ptrdiff_t... OtherDimensions,
-              typename = std::enable_if_t<std::is_same<
-                  std::remove_cv_t<value_type>, std::remove_cv_t<OtherValueType>>::value>>
-    constexpr bool
-    operator>=(const multi_span<OtherValueType, OtherDimensions...>& other) const noexcept
+              typename = std::enable_if_t<std::is_same<std::remove_cv_t<value_type>,
+                                                       std::remove_cv_t<OtherValueType>>::value>>
+    constexpr bool operator>=(const multi_span<OtherValueType, OtherDimensions...>& other) const
     {
         return !(*this < other);
     }
@@ -1610,7 +1666,7 @@ constexpr auto as_multi_span(SpanType s, Dimensions2... dims)
                   "Variadic as_multi_span() is for reshaping existing spans.");
     using BoundsType =
         typename multi_span<typename SpanType::value_type, (Dimensions2::value)...>::bounds_type;
-    auto tobounds = details::static_as_multi_span_helper<BoundsType>(dims..., details::Sep{});
+    const auto tobounds = details::static_as_multi_span_helper<BoundsType>(dims..., details::Sep{});
     details::verifyBoundsReshape(s.bounds(), tobounds);
     return {s.data(), tobounds};
 }
@@ -1641,8 +1697,7 @@ multi_span<byte> as_writeable_bytes(multi_span<U, Dimensions...> s) noexcept
 // on all implementations. It should be considered an experimental extension
 // to the standard GSL interface.
 template <typename U, std::ptrdiff_t... Dimensions>
-constexpr auto
-as_multi_span(multi_span<const byte, Dimensions...> s) -> multi_span<
+constexpr auto as_multi_span(multi_span<const byte, Dimensions...> s) -> multi_span<
     const U, static_cast<std::ptrdiff_t>(
                  multi_span<const byte, Dimensions...>::bounds_type::static_size != dynamic_range
                      ? (static_cast<std::size_t>(
@@ -1677,11 +1732,10 @@ constexpr auto as_multi_span(multi_span<byte, Dimensions...> s)
                              : dynamic_range)>
 {
     using ByteSpan = multi_span<byte, Dimensions...>;
-    static_assert(
-        std::is_trivial<std::decay_t<U>>::value &&
-            (ByteSpan::bounds_type::static_size == dynamic_range ||
-             ByteSpan::bounds_type::static_size % sizeof(U) == 0),
-        "Target type must be a trivial type and its size must match the byte array size");
+    static_assert(std::is_trivial<std::decay_t<U>>::value &&
+                      (ByteSpan::bounds_type::static_size == dynamic_range ||
+                       ByteSpan::bounds_type::static_size % sizeof(U) == 0),
+                  "Target type must be a trivial type and its size must match the byte array size");
 
     Expects((s.size_bytes() % sizeof(U)) == 0);
     return {reinterpret_cast<U*>(s.data()),
@@ -1747,6 +1801,7 @@ constexpr auto as_multi_span(Cont&& arr) -> std::enable_if_t<
 
 // from basic_string which doesn't have nonconst .data() member like other contiguous containers
 template <typename CharT, typename Traits, typename Allocator>
+GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
 constexpr auto as_multi_span(std::basic_string<CharT, Traits, Allocator>& str)
     -> multi_span<CharT, dynamic_range>
 {
@@ -1792,6 +1847,7 @@ public:
         Expects((bounds_.size() > 0 && ptr != nullptr) || bounds_.size() == 0);
         // Bounds cross data boundaries
         Expects(this->bounds().total_size() <= size);
+        GSL_SUPPRESS(type.4) // NO-FORMAT: attribute // TODO: false positive
         (void) size;
     }
 
@@ -1799,8 +1855,7 @@ public:
     template <size_type N>
     constexpr strided_span(value_type (&values)[N], bounds_type bounds)
         : strided_span(values, N, std::move(bounds))
-    {
-    }
+    {}
 
     // from array view
     template <typename OtherValueType, std::ptrdiff_t... Dimensions,
@@ -1809,16 +1864,14 @@ public:
               typename = std::enable_if_t<Enabled1 && Enabled2>>
     constexpr strided_span(multi_span<OtherValueType, Dimensions...> av, bounds_type bounds)
         : strided_span(av.data(), av.bounds().total_size(), std::move(bounds))
-    {
-    }
+    {}
 
     // convertible
     template <typename OtherValueType, typename = std::enable_if_t<std::is_convertible<
                                            OtherValueType (*)[], value_type (*)[]>::value>>
     constexpr strided_span(const strided_span<OtherValueType, Rank>& other)
         : data_(other.data_), bounds_(other.bounds_)
-    {
-    }
+    {}
 
     // convert from bytes
     template <typename OtherValueType>
@@ -1832,7 +1885,7 @@ public:
                       "OtherValueType should have a size to contain a multiple of ValueTypes");
         auto d = narrow_cast<size_type>(sizeof(OtherValueType) / sizeof(value_type));
 
-        size_type size = this->bounds().total_size() / d;
+        const size_type size = this->bounds().total_size() / d;
         return {const_cast<OtherValueType*>(reinterpret_cast<const OtherValueType*>(this->data())),
                 size,
                 bounds_type{resize_extent(this->bounds().index_bounds(), d),
@@ -1841,17 +1894,19 @@ public:
 
     constexpr strided_span section(index_type origin, index_type extents) const
     {
-        size_type size = this->bounds().total_size() - this->bounds().linearize(origin);
+        const size_type size = this->bounds().total_size() - this->bounds().linearize(origin);
         return {&this->operator[](origin), size,
                 bounds_type{extents, details::make_stride(bounds())}};
     }
 
+    GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
     constexpr reference operator[](const index_type& idx) const
     {
         return data_[bounds_.linearize(idx)];
     }
 
     template <bool Enabled = (Rank > 1), typename Ret = std::enable_if_t<Enabled, sliced_type>>
+    GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
     constexpr Ret operator[](size_type idx) const
     {
         Expects(idx < bounds_.size()); // index is out of bounds of the array
@@ -1901,56 +1956,50 @@ public:
     constexpr const_reverse_iterator crend() const { return const_reverse_iterator{cbegin()}; }
 
     template <typename OtherValueType, std::ptrdiff_t OtherRank,
-              typename = std::enable_if_t<std::is_same<
-                  std::remove_cv_t<value_type>, std::remove_cv_t<OtherValueType>>::value>>
-    constexpr bool
-    operator==(const strided_span<OtherValueType, OtherRank>& other) const
+              typename = std::enable_if_t<std::is_same<std::remove_cv_t<value_type>,
+                                                       std::remove_cv_t<OtherValueType>>::value>>
+    constexpr bool operator==(const strided_span<OtherValueType, OtherRank>& other) const
     {
         return bounds_.size() == other.bounds_.size() &&
                (data_ == other.data_ || std::equal(this->begin(), this->end(), other.begin()));
     }
 
     template <typename OtherValueType, std::ptrdiff_t OtherRank,
-              typename = std::enable_if_t<std::is_same<
-                  std::remove_cv_t<value_type>, std::remove_cv_t<OtherValueType>>::value>>
-    constexpr bool
-    operator!=(const strided_span<OtherValueType, OtherRank>& other) const
+              typename = std::enable_if_t<std::is_same<std::remove_cv_t<value_type>,
+                                                       std::remove_cv_t<OtherValueType>>::value>>
+    constexpr bool operator!=(const strided_span<OtherValueType, OtherRank>& other) const
     {
         return !(*this == other);
     }
 
     template <typename OtherValueType, std::ptrdiff_t OtherRank,
-              typename = std::enable_if_t<std::is_same<
-                  std::remove_cv_t<value_type>, std::remove_cv_t<OtherValueType>>::value>>
-    constexpr bool
-    operator<(const strided_span<OtherValueType, OtherRank>& other) const
+              typename = std::enable_if_t<std::is_same<std::remove_cv_t<value_type>,
+                                                       std::remove_cv_t<OtherValueType>>::value>>
+    constexpr bool operator<(const strided_span<OtherValueType, OtherRank>& other) const
     {
         return std::lexicographical_compare(this->begin(), this->end(), other.begin(), other.end());
     }
 
     template <typename OtherValueType, std::ptrdiff_t OtherRank,
-              typename = std::enable_if_t<std::is_same<
-                  std::remove_cv_t<value_type>, std::remove_cv_t<OtherValueType>>::value>>
-    constexpr bool
-    operator<=(const strided_span<OtherValueType, OtherRank>& other) const
+              typename = std::enable_if_t<std::is_same<std::remove_cv_t<value_type>,
+                                                       std::remove_cv_t<OtherValueType>>::value>>
+    constexpr bool operator<=(const strided_span<OtherValueType, OtherRank>& other) const
     {
         return !(other < *this);
     }
 
     template <typename OtherValueType, std::ptrdiff_t OtherRank,
-              typename = std::enable_if_t<std::is_same<
-                  std::remove_cv_t<value_type>, std::remove_cv_t<OtherValueType>>::value>>
-    constexpr bool
-    operator>(const strided_span<OtherValueType, OtherRank>& other) const
+              typename = std::enable_if_t<std::is_same<std::remove_cv_t<value_type>,
+                                                       std::remove_cv_t<OtherValueType>>::value>>
+    constexpr bool operator>(const strided_span<OtherValueType, OtherRank>& other) const
     {
         return (other < *this);
     }
 
     template <typename OtherValueType, std::ptrdiff_t OtherRank,
-              typename = std::enable_if_t<std::is_same<
-                  std::remove_cv_t<value_type>, std::remove_cv_t<OtherValueType>>::value>>
-    constexpr bool
-    operator>=(const strided_span<OtherValueType, OtherRank>& other) const
+              typename = std::enable_if_t<std::is_same<std::remove_cv_t<value_type>,
+                                                       std::remove_cv_t<OtherValueType>>::value>>
+    constexpr bool operator>=(const strided_span<OtherValueType, OtherRank>& other) const
     {
         return !(*this < other);
     }
@@ -1959,6 +2008,7 @@ private:
     static index_type resize_extent(const index_type& extent, std::ptrdiff_t d)
     {
         // The last dimension of the array needs to contain a multiple of new type elements
+        GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
         Expects(extent[Rank - 1] >= d && (extent[Rank - 1] % d == 0));
 
         index_type ret = extent;
@@ -1971,12 +2021,14 @@ private:
     static index_type resize_stride(const index_type& strides, std::ptrdiff_t, void* = nullptr)
     {
         // Only strided arrays with regular strides can be resized
+        GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
         Expects(strides[Rank - 1] == 1);
 
         return strides;
     }
 
     template <bool Enabled = (Rank > 1), typename = std::enable_if_t<Enabled>>
+    GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
     static index_type resize_stride(const index_type& strides, std::ptrdiff_t d)
     {
         // Only strided arrays with regular strides can be resized
@@ -1985,7 +2037,8 @@ private:
         // memory that can contain a multiple of new type elements
         Expects(strides[Rank - 2] >= d && (strides[Rank - 2] % d == 0));
 
-        for (std::size_t i = Rank - 1; i > 0; --i) {
+        for (std::size_t i = Rank - 1; i > 0; --i)
+        {
             // Only strided arrays with regular strides can be resized
             Expects((strides[i - 1] >= strides[i]) && (strides[i - 1] % strides[i] == 0));
         }
@@ -2013,16 +2066,18 @@ private:
 
     pointer data_;
     const Span* m_validator;
-    void validateThis() const
-    {
+
+    GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
+    void validateThis() const {
         // iterator is out of range of the array
         Expects(data_ >= m_validator->data_ && data_ < m_validator->data_ + m_validator->size());
     }
+
+    GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
     contiguous_span_iterator(const Span* container, bool isbegin)
         : data_(isbegin ? container->data_ : container->data_ + container->size())
         , m_validator(container)
-    {
-    }
+    {}
 
 public:
     reference operator*() const
@@ -2035,6 +2090,8 @@ public:
         validateThis();
         return data_;
     }
+
+    GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
     contiguous_span_iterator& operator++() noexcept
     {
         ++data_;
@@ -2046,6 +2103,8 @@ public:
         ++(*this);
         return ret;
     }
+
+    GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
     contiguous_span_iterator& operator--() noexcept
     {
         --data_;
@@ -2072,7 +2131,8 @@ public:
         contiguous_span_iterator ret{*this};
         return ret -= n;
     }
-    contiguous_span_iterator& operator-=(difference_type n) noexcept { return *this += -n; }
+
+    contiguous_span_iterator& operator-=(difference_type n) { return *this += -n; }
     difference_type operator-(const contiguous_span_iterator& rhs) const
     {
         Expects(m_validator == rhs.m_validator);
@@ -2084,24 +2144,19 @@ public:
         Expects(m_validator == rhs.m_validator);
         return data_ == rhs.data_;
     }
-    bool operator!=(const contiguous_span_iterator& rhs) const
-    {
-        return !(*this == rhs);
-    }
+
+    bool operator!=(const contiguous_span_iterator& rhs) const { return !(*this == rhs); }
+
     bool operator<(const contiguous_span_iterator& rhs) const
     {
         Expects(m_validator == rhs.m_validator);
         return data_ < rhs.data_;
     }
-    bool operator<=(const contiguous_span_iterator& rhs) const
-    {
-        return !(rhs < *this);
-    }
+
+    bool operator<=(const contiguous_span_iterator& rhs) const { return !(rhs < *this); }
     bool operator>(const contiguous_span_iterator& rhs) const { return rhs < *this; }
-    bool operator>=(const contiguous_span_iterator& rhs) const
-    {
-        return !(rhs > *this);
-    }
+    bool operator>=(const contiguous_span_iterator& rhs) const { return !(rhs > *this); }
+
     void swap(contiguous_span_iterator& rhs) noexcept
     {
         std::swap(data_, rhs.data_);
@@ -2117,8 +2172,7 @@ contiguous_span_iterator<Span> operator+(typename contiguous_span_iterator<Span>
 }
 
 template <typename Span>
-class general_span_iterator
-{
+class general_span_iterator {
 public:
     using iterator_category = std::random_access_iterator_tag;
     using value_type = typename Span::value_type;
@@ -2135,8 +2189,7 @@ private:
     general_span_iterator(const Span* container, bool isbegin)
         : m_container(container)
         , m_itr(isbegin ? m_container->bounds().begin() : m_container->bounds().end())
-    {
-    }
+    {}
 
 public:
     reference operator*() noexcept { return (*m_container)[*m_itr]; }
@@ -2184,6 +2237,8 @@ public:
         Expects(m_container == rhs.m_container);
         return m_itr - rhs.m_itr;
     }
+
+    GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute
     value_type operator[](difference_type n) const { return (*m_container)[m_itr[n]]; }
 
     bool operator==(const general_span_iterator& rhs) const
@@ -2227,7 +2282,7 @@ general_span_iterator<Span> operator+(typename general_span_iterator<Span>::diff
 
 #endif // _MSC_VER
 
-#if __GNUC__ > 6 
+#if __GNUC__ > 6
 #pragma GCC diagnostic pop
 #endif // __GNUC__ > 6
 
diff --git a/include/gsl/span b/include/gsl/span
index 2fa9cc5..3e5a053 100644
--- a/include/gsl/span
+++ b/include/gsl/span
@@ -37,10 +37,9 @@
 #pragma warning(disable : 4127) // conditional expression is constant
 #pragma warning(disable : 4702) // unreachable code
 
-// blanket turn off warnings from CppCoreCheck for now
-// so people aren't annoyed by them when running the tool.
-// more targeted suppressions will be added in a future update to the GSL
-#pragma warning(disable : 26481 26482 26483 26485 26490 26491 26492 26493 26495)
+// Turn MSVC /analyze rules that generate too much noise. TODO: fix in the tool.
+#pragma warning(disable : 26495) // uninitalized member when constructor calls constructor
+#pragma warning(disable : 26446) // parser bug does not allow attributes on some templates
 
 #if _MSC_VER < 1910
 #pragma push_macro("constexpr")
@@ -48,7 +47,7 @@
 #define GSL_USE_STATIC_CONSTEXPR_WORKAROUND
 
 #endif                          // _MSC_VER < 1910
-#else                           // _MSC_VER
+#endif                          // _MSC_VER
 
 // See if we have enough C++17 power to use a static constexpr data member
 // without needing an out-of-line definition
@@ -56,12 +55,10 @@
 #define GSL_USE_STATIC_CONSTEXPR_WORKAROUND
 #endif // !(defined(__cplusplus) && (__cplusplus >= 201703L))
 
-#endif                          // _MSC_VER
-
 // GCC 7 does not like the signed unsigned missmatch (size_t ptrdiff_t)
-// While there is a conversion from signed to unsigned, it happens at 
-// compiletime, so the compiler wouldn't have to warn indiscriminently, but 
-// could check if the source value actually doesn't fit into the target type 
+// While there is a conversion from signed to unsigned, it happens at
+// compiletime, so the compiler wouldn't have to warn indiscriminently, but
+// could check if the source value actually doesn't fit into the target type
 // and only warn in those cases.
 #if __GNUC__ > 6
 #pragma GCC diagnostic push
@@ -129,7 +126,6 @@ namespace details
         using element_type_ = typename Span::element_type;
 
     public:
-
 #ifdef _MSC_VER
         // Tell Microsoft standard library that span_iterators are checked.
         using _Unchecked_type = typename Span::pointer;
@@ -146,15 +142,17 @@ namespace details
 
         constexpr span_iterator(const Span* span, typename Span::index_type idx) noexcept
             : span_(span), index_(idx)
-        {}
+        {
+        }
 
         friend span_iterator<Span, true>;
-        template<bool B, std::enable_if_t<!B && IsConst>* = nullptr>
+        template <bool B, std::enable_if_t<!B && IsConst>* = nullptr>
         constexpr span_iterator(const span_iterator<Span, B>& other) noexcept
             : span_iterator(other.span_, other.index_)
         {
         }
 
+        GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
         constexpr reference operator*() const
         {
             Expects(index_ != span_->size());
@@ -227,43 +225,34 @@ namespace details
             return index_ - rhs.index_;
         }
 
-        constexpr reference operator[](difference_type n) const
-        {
-            return *(*this + n);
-        }
+        constexpr reference operator[](difference_type n) const { return *(*this + n); }
 
-        constexpr friend bool operator==(span_iterator lhs,
-                                         span_iterator rhs) noexcept
+        constexpr friend bool operator==(span_iterator lhs, span_iterator rhs) noexcept
         {
             return lhs.span_ == rhs.span_ && lhs.index_ == rhs.index_;
         }
 
-        constexpr friend bool operator!=(span_iterator lhs,
-                                         span_iterator rhs) noexcept
+        constexpr friend bool operator!=(span_iterator lhs, span_iterator rhs) noexcept
         {
             return !(lhs == rhs);
         }
 
-        constexpr friend bool operator<(span_iterator lhs,
-                                        span_iterator rhs) noexcept
+        constexpr friend bool operator<(span_iterator lhs, span_iterator rhs) noexcept
         {
             return lhs.index_ < rhs.index_;
         }
 
-        constexpr friend bool operator<=(span_iterator lhs,
-                                         span_iterator rhs) noexcept
+        constexpr friend bool operator<=(span_iterator lhs, span_iterator rhs) noexcept
         {
             return !(rhs < lhs);
         }
 
-        constexpr friend bool operator>(span_iterator lhs,
-                                        span_iterator rhs) noexcept
+        constexpr friend bool operator>(span_iterator lhs, span_iterator rhs) noexcept
         {
             return rhs < lhs;
         }
 
-        constexpr friend bool operator>=(span_iterator lhs,
-                                         span_iterator rhs) noexcept
+        constexpr friend bool operator>=(span_iterator lhs, span_iterator rhs) noexcept
         {
             return !(rhs > lhs);
         }
@@ -272,21 +261,21 @@ namespace details
         // MSVC++ iterator debugging support; allows STL algorithms in 15.8+
         // to unwrap span_iterator to a pointer type after a range check in STL
         // algorithm calls
-        friend constexpr void _Verify_range(span_iterator lhs,
-                                            span_iterator rhs) noexcept
-        {   // test that [lhs, rhs) forms a valid range inside an STL algorithm
-            Expects(lhs.span_ == rhs.span_ // range spans have to match
-                && lhs.index_ <= rhs.index_); // range must not be transposed
+        friend constexpr void _Verify_range(span_iterator lhs, span_iterator rhs) noexcept
+        { // test that [lhs, rhs) forms a valid range inside an STL algorithm
+            Expects(lhs.span_ == rhs.span_        // range spans have to match
+                    && lhs.index_ <= rhs.index_); // range must not be transposed
         }
 
         constexpr void _Verify_offset(const difference_type n) const noexcept
-        {   // test that the iterator *this + n is a valid range in an STL
+        { // test that the iterator *this + n is a valid range in an STL
             // algorithm call
             Expects((index_ + n) >= 0 && (index_ + n) <= span_->size());
         }
 
+        GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
         constexpr pointer _Unwrapped() const noexcept
-        {   // after seeking *this to a high water mark, or using one of the
+        { // after seeking *this to a high water mark, or using one of the
             // _Verify_xxx functions above, unwrap this span_iterator to a raw
             // pointer
             return span_->data() + index_;
@@ -299,8 +288,9 @@ namespace details
 #else
         static constexpr bool _Unwrap_when_unverified = false;
 #endif
+        GSL_SUPPRESS(con.3) // NO-FORMAT: attribute // TODO: false positive
         constexpr void _Seek_to(const pointer p) noexcept
-        {   // adjust the position of *this to previously verified location p
+        { // adjust the position of *this to previously verified location p
             // after _Unwrapped
             index_ = p - span_->data();
         }
@@ -356,7 +346,9 @@ namespace details
     template <class ElementType, std::ptrdiff_t Extent, std::ptrdiff_t Offset, std::ptrdiff_t Count>
     struct calculate_subspan_type
     {
-      using type = span<ElementType, Count != dynamic_extent ? Count : (Extent != dynamic_extent ? Extent - Offset : Extent)>;
+        using type = span<ElementType, Count != dynamic_extent
+                                           ? Count
+                                           : (Extent != dynamic_extent ? Extent - Offset : Extent)>;
     };
 } // namespace details
 
@@ -380,9 +372,9 @@ public:
     using size_type = index_type;
 
 #if defined(GSL_USE_STATIC_CONSTEXPR_WORKAROUND)
-    static constexpr const index_type extent { Extent };
+    static constexpr const index_type extent{Extent};
 #else
-    static constexpr index_type extent { Extent };
+    static constexpr index_type extent{Extent};
 #endif
 
     // [span.cons], span constructors, copy, assignment, and destructor
@@ -408,12 +400,14 @@ public:
     }
 
     template <std::size_t N, class ArrayElementType = std::remove_const_t<element_type>>
+    // GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute // TODO: parser bug
     constexpr span(std::array<ArrayElementType, N>& arr) noexcept
         : storage_(&arr[0], details::extent_type<N>())
     {
     }
 
     template <std::size_t N>
+    // GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute // TODO: parser bug
     constexpr span(const std::array<std::remove_const_t<element_type>, N>& arr) noexcept
         : storage_(&arr[0], details::extent_type<N>())
     {
@@ -465,6 +459,7 @@ public:
     }
 
     template <std::ptrdiff_t Count>
+    GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
     constexpr span<element_type, Count> last() const
     {
         Expects(Count >= 0 && size() - Count >= 0);
@@ -472,7 +467,9 @@ public:
     }
 
     template <std::ptrdiff_t Offset, std::ptrdiff_t Count = dynamic_extent>
-    constexpr auto subspan() const -> typename details::calculate_subspan_type<ElementType, Extent, Offset, Count>::type
+    GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
+    constexpr auto subspan() const ->
+        typename details::calculate_subspan_type<ElementType, Extent, Offset, Count>::type
     {
         Expects((Offset >= 0 && size() - Offset >= 0) &&
                 (Count == dynamic_extent || (Count >= 0 && Offset + Count <= size())));
@@ -497,7 +494,6 @@ public:
         return make_subspan(offset, count, subspan_selector<Extent>{});
     }
 
-
     // [span.obs], span observers
     constexpr index_type size() const noexcept { return storage_.size(); }
     constexpr index_type size_bytes() const noexcept
@@ -507,6 +503,7 @@ public:
     constexpr bool empty() const noexcept { return size() == 0; }
 
     // [span.elem], span element access
+    GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
     constexpr reference operator[](index_type idx) const
     {
         Expects(idx >= 0 && idx < storage_.size());
@@ -527,17 +524,26 @@ public:
     constexpr reverse_iterator rbegin() const noexcept { return reverse_iterator{end()}; }
     constexpr reverse_iterator rend() const noexcept { return reverse_iterator{begin()}; }
 
-    constexpr const_reverse_iterator crbegin() const noexcept { return const_reverse_iterator{cend()}; }
-    constexpr const_reverse_iterator crend() const noexcept { return const_reverse_iterator{cbegin()}; }
+    constexpr const_reverse_iterator crbegin() const noexcept
+    {
+        return const_reverse_iterator{cend()};
+    }
+    constexpr const_reverse_iterator crend() const noexcept
+    {
+        return const_reverse_iterator{cbegin()};
+    }
 
 #ifdef _MSC_VER
     // Tell MSVC how to unwrap spans in range-based-for
     constexpr pointer _Unchecked_begin() const noexcept { return data(); }
-    constexpr pointer _Unchecked_end() const noexcept { return data() + size(); }
+    constexpr pointer _Unchecked_end() const noexcept 
+    {
+        GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
+        return data() + size();
+    }
 #endif // _MSC_VER
 
 private:
-
     // Needed to remove unnecessary null check in subspans
     struct KnownNotNull
     {
@@ -554,17 +560,17 @@ private:
         // KnownNotNull parameter is needed to remove unnecessary null check
         // in subspans and constructors from arrays
         template <class OtherExtentType>
-        constexpr storage_type(KnownNotNull data, OtherExtentType ext) : ExtentType(ext), data_(data.p)
+        constexpr storage_type(KnownNotNull data, OtherExtentType ext)
+            : ExtentType(ext), data_(data.p)
         {
-             Expects(ExtentType::size() >= 0);
+            Expects(ExtentType::size() >= 0);
         }
 
-
         template <class OtherExtentType>
         constexpr storage_type(pointer data, OtherExtentType ext) : ExtentType(ext), data_(data)
         {
-             Expects(ExtentType::size() >= 0);
-             Expects(data || ExtentType::size() == 0);
+            Expects(ExtentType::size() >= 0);
+            Expects(data || ExtentType::size() == 0);
         }
 
         constexpr pointer data() const noexcept { return data_; }
@@ -580,29 +586,28 @@ private:
     constexpr span(KnownNotNull ptr, index_type count) : storage_(ptr, count) {}
 
     template <std::ptrdiff_t CallerExtent>
-    class subspan_selector {};
+    class subspan_selector
+    {
+    };
 
     template <std::ptrdiff_t CallerExtent>
-    span<element_type, dynamic_extent> make_subspan(index_type offset,
-                                                    index_type count,
+    span<element_type, dynamic_extent> make_subspan(index_type offset, index_type count,
                                                     subspan_selector<CallerExtent>) const
     {
-        span<element_type, dynamic_extent> tmp(*this);
+        const span<element_type, dynamic_extent> tmp(*this);
         return tmp.subspan(offset, count);
     }
 
-    span<element_type, dynamic_extent> make_subspan(index_type offset,
-                                                    index_type count,
+    GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute
+    span<element_type, dynamic_extent> make_subspan(index_type offset, index_type count,
                                                     subspan_selector<dynamic_extent>) const
     {
         Expects(offset >= 0 && size() - offset >= 0);
-        if (count == dynamic_extent)
-        {
-            return { KnownNotNull{ data() + offset }, size() - offset };
-        }
+
+        if (count == dynamic_extent) { return {KnownNotNull{data() + offset}, size() - offset}; }
 
         Expects(count >= 0 && size() - offset >= count);
-        return { KnownNotNull{ data() + offset },  count };
+        return {KnownNotNull{data() + offset}, count};
     }
 };
 
@@ -611,46 +616,39 @@ template <class ElementType, std::ptrdiff_t Extent>
 constexpr const typename span<ElementType, Extent>::index_type span<ElementType, Extent>::extent;
 #endif
 
-
 // [span.comparison], span comparison operators
 template <class ElementType, std::ptrdiff_t FirstExtent, std::ptrdiff_t SecondExtent>
-constexpr bool operator==(span<ElementType, FirstExtent> l,
-                          span<ElementType, SecondExtent> r)
+constexpr bool operator==(span<ElementType, FirstExtent> l, span<ElementType, SecondExtent> r)
 {
     return std::equal(l.begin(), l.end(), r.begin(), r.end());
 }
 
 template <class ElementType, std::ptrdiff_t Extent>
-constexpr bool operator!=(span<ElementType, Extent> l,
-                          span<ElementType, Extent> r)
+constexpr bool operator!=(span<ElementType, Extent> l, span<ElementType, Extent> r)
 {
     return !(l == r);
 }
 
 template <class ElementType, std::ptrdiff_t Extent>
-constexpr bool operator<(span<ElementType, Extent> l,
-                         span<ElementType, Extent> r)
+constexpr bool operator<(span<ElementType, Extent> l, span<ElementType, Extent> r)
 {
     return std::lexicographical_compare(l.begin(), l.end(), r.begin(), r.end());
 }
 
 template <class ElementType, std::ptrdiff_t Extent>
-constexpr bool operator<=(span<ElementType, Extent> l,
-                          span<ElementType, Extent> r)
+constexpr bool operator<=(span<ElementType, Extent> l, span<ElementType, Extent> r)
 {
     return !(l > r);
 }
 
 template <class ElementType, std::ptrdiff_t Extent>
-constexpr bool operator>(span<ElementType, Extent> l,
-                         span<ElementType, Extent> r)
+constexpr bool operator>(span<ElementType, Extent> l, span<ElementType, Extent> r)
 {
     return r < l;
 }
 
 template <class ElementType, std::ptrdiff_t Extent>
-constexpr bool operator>=(span<ElementType, Extent> l,
-                          span<ElementType, Extent> r)
+constexpr bool operator>=(span<ElementType, Extent> l, span<ElementType, Extent> r)
 {
     return !(l < r);
 }
@@ -676,13 +674,14 @@ namespace details
         : std::integral_constant<std::ptrdiff_t, dynamic_extent>
     {
     };
-}
+} // namespace details
 
 // [span.objectrep], views of object representation
 template <class ElementType, std::ptrdiff_t Extent>
 span<const byte, details::calculate_byte_size<ElementType, Extent>::value>
 as_bytes(span<ElementType, Extent> s) noexcept
 {
+    GSL_SUPPRESS(type.1) // NO-FORMAT: attribute
     return {reinterpret_cast<const byte*>(s.data()), s.size_bytes()};
 }
 
@@ -691,6 +690,7 @@ template <class ElementType, std::ptrdiff_t Extent,
 span<byte, details::calculate_byte_size<ElementType, Extent>::value>
 as_writeable_bytes(span<ElementType, Extent> s) noexcept
 {
+    GSL_SUPPRESS(type.1) // NO-FORMAT: attribute
     return {reinterpret_cast<byte*>(s.data()), s.size_bytes()};
 }
 
@@ -698,7 +698,8 @@ as_writeable_bytes(span<ElementType, Extent> s) noexcept
 // make_span() - Utility functions for creating spans
 //
 template <class ElementType>
-constexpr span<ElementType> make_span(ElementType* ptr, typename span<ElementType>::index_type count)
+constexpr span<ElementType> make_span(ElementType* ptr,
+                                      typename span<ElementType>::index_type count)
 {
     return span<ElementType>(ptr, count);
 }
@@ -759,7 +760,7 @@ constexpr ElementType& at(span<ElementType, Extent> s, index i)
 #pragma warning(pop)
 #endif // _MSC_VER
 
-#if __GNUC__ > 6 
+#if __GNUC__ > 6
 #pragma GCC diagnostic pop
 #endif // __GNUC__ > 6
 
diff --git a/include/gsl/string_span b/include/gsl/string_span
index 2a89561..d298039 100644
--- a/include/gsl/string_span
+++ b/include/gsl/string_span
@@ -20,6 +20,7 @@
 #include <gsl/gsl_assert> // for Ensures, Expects
 #include <gsl/gsl_util>   // for narrow_cast
 #include <gsl/span>       // for operator!=, operator==, dynamic_extent
+#include <gsl/pointers>   // for not_null
 
 #include <algorithm> // for equal, lexicographical_compare
 #include <array>     // for array
@@ -32,10 +33,9 @@
 #ifdef _MSC_VER
 #pragma warning(push)
 
-// blanket turn off warnings from CppCoreCheck for now
-// so people aren't annoyed by them when running the tool.
-// more targeted suppressions will be added in a future update to the GSL
-#pragma warning(disable : 26481 26482 26483 26485 26490 26491 26492 26493 26495)
+// Turn MSVC /analyze rules that generate too much noise. TODO: fix in the tool.
+#pragma warning(disable : 26446) // TODO: bug in parser - attributes and templates
+#pragma warning(disable : 26481) // TODO: suppress does not work inside templates sometimes
 
 #if _MSC_VER < 1910
 #pragma push_macro("constexpr")
@@ -98,7 +98,7 @@ namespace details
 
         return len;
     }
-}
+} // namespace details
 
 //
 // ensure_sentinel()
@@ -111,7 +111,13 @@ namespace details
 template <typename T, const T Sentinel>
 span<T, dynamic_extent> ensure_sentinel(T* seq, std::ptrdiff_t max = PTRDIFF_MAX)
 {
+    Ensures(seq != nullptr);
+
+    GSL_SUPPRESS(f.23) // NO-FORMAT: attribute // TODO: false positive // TODO: suppress does not work
     auto cur = seq;
+    Ensures(cur != nullptr); // workaround for removing the warning
+
+    GSL_SUPPRESS(bounds.1) // NO-FORMAT: attribute // TODO: suppress does not work
     while ((cur - seq) < max && *cur != Sentinel) ++cur;
     Ensures(*cur == Sentinel);
     return {seq, cur - seq};
@@ -131,21 +137,20 @@ span<CharT, dynamic_extent> ensure_z(CharT* const& sz, std::ptrdiff_t max = PTRD
 template <typename CharT, std::size_t N>
 span<CharT, dynamic_extent> ensure_z(CharT (&sz)[N])
 {
-    return ensure_z(&sz[0], static_cast<std::ptrdiff_t>(N));
+    return ensure_z(&sz[0], narrow_cast<std::ptrdiff_t>(N));
 }
 
 template <class Cont>
 span<typename std::remove_pointer<typename Cont::pointer>::type, dynamic_extent>
 ensure_z(Cont& cont)
 {
-    return ensure_z(cont.data(), static_cast<std::ptrdiff_t>(cont.size()));
+    return ensure_z(cont.data(), narrow_cast<std::ptrdiff_t>(cont.size()));
 }
 
 template <typename CharT, std::ptrdiff_t>
 class basic_string_span;
 
-namespace details
-{
+namespace details {
     template <typename T>
     struct is_basic_string_span_oracle : std::false_type
     {
@@ -160,7 +165,7 @@ namespace details
     struct is_basic_string_span : is_basic_string_span_oracle<std::remove_cv_t<T>>
     {
     };
-}
+} // namespace details
 
 //
 // string_span and relatives
@@ -197,32 +202,27 @@ public:
     // All other containers allow 0s within the length, so we do not remove them
     template <std::size_t N>
     constexpr basic_string_span(element_type (&arr)[N]) : span_(remove_z(arr))
-    {
-    }
+    {}
 
     template <std::size_t N, class ArrayElementType = std::remove_const_t<element_type>>
     constexpr basic_string_span(std::array<ArrayElementType, N>& arr) noexcept : span_(arr)
-    {
-    }
+    {}
 
     template <std::size_t N, class ArrayElementType = std::remove_const_t<element_type>>
-    constexpr basic_string_span(const std::array<ArrayElementType, N>& arr) noexcept
-        : span_(arr)
-    {
-    }
+    constexpr basic_string_span(const std::array<ArrayElementType, N>& arr) noexcept : span_(arr)
+    {}
 
     // Container signature should work for basic_string after C++17 version exists
     template <class Traits, class Allocator>
+    // GSL_SUPPRESS(bounds.4) // NO-FORMAT: attribute // TODO: parser bug
     constexpr basic_string_span(std::basic_string<element_type, Traits, Allocator>& str)
         : span_(&str[0], narrow_cast<std::ptrdiff_t>(str.length()))
-    {
-    }
+    {}
 
     template <class Traits, class Allocator>
     constexpr basic_string_span(const std::basic_string<element_type, Traits, Allocator>& str)
         : span_(&str[0], str.length())
-    {
-    }
+    {}
 
     // from containers. Containers must have a pointer type and data() function signatures
     template <class Container,
@@ -232,8 +232,7 @@ public:
                   std::is_convertible<typename Container::pointer,
                                       decltype(std::declval<Container>().data())>::value>>
     constexpr basic_string_span(Container& cont) : span_(cont)
-    {
-    }
+    {}
 
     template <class Container,
               class = std::enable_if_t<
@@ -242,8 +241,7 @@ public:
                   std::is_convertible<typename Container::pointer,
                                       decltype(std::declval<Container>().data())>::value>>
     constexpr basic_string_span(const Container& cont) : span_(cont)
-    {
-    }
+    {}
 
     // from string_span
     template <
@@ -252,8 +250,7 @@ public:
             typename basic_string_span<OtherValueType, OtherExtent>::impl_type, impl_type>::value>>
     constexpr basic_string_span(basic_string_span<OtherValueType, OtherExtent> other)
         : span_(other.data(), other.length())
-    {
-    }
+    {}
 
     template <index_type Count>
     constexpr basic_string_span<element_type, Count> first() const
@@ -359,21 +356,22 @@ template <typename CharT, std::ptrdiff_t Extent>
 std::basic_string<typename std::remove_const<CharT>::type>
 to_string(basic_string_span<CharT, Extent> view)
 {
-    return {view.data(), static_cast<std::size_t>(view.length())};
+    return {view.data(), narrow_cast<std::size_t>(view.length())};
 }
 
 template <typename CharT, typename Traits = typename std::char_traits<CharT>,
           typename Allocator = std::allocator<CharT>, typename gCharT, std::ptrdiff_t Extent>
 std::basic_string<CharT, Traits, Allocator> to_basic_string(basic_string_span<gCharT, Extent> view)
 {
-    return {view.data(), static_cast<std::size_t>(view.length())};
+    return {view.data(), narrow_cast<std::size_t>(view.length())};
 }
 
 template <class ElementType, std::ptrdiff_t Extent>
 basic_string_span<const byte, details::calculate_byte_size<ElementType, Extent>::value>
 as_bytes(basic_string_span<ElementType, Extent> s) noexcept
 {
-	return { reinterpret_cast<const byte*>(s.data()), s.size_bytes() };
+    GSL_SUPPRESS(type.1) // NO-FORMAT: attribute
+    return {reinterpret_cast<const byte*>(s.data()), s.size_bytes()};
 }
 
 template <class ElementType, std::ptrdiff_t Extent,
@@ -381,14 +379,14 @@ template <class ElementType, std::ptrdiff_t Extent,
 basic_string_span<byte, details::calculate_byte_size<ElementType, Extent>::value>
 as_writeable_bytes(basic_string_span<ElementType, Extent> s) noexcept
 {
+    GSL_SUPPRESS(type.1) // NO-FORMAT: attribute
     return {reinterpret_cast<byte*>(s.data()), s.size_bytes()};
 }
 
 // zero-terminated string span, used to convert
 // zero-terminated spans to legacy strings
 template <typename CharT, std::ptrdiff_t Extent = dynamic_extent>
-class basic_zstring_span
-{
+class basic_zstring_span {
 public:
     using value_type = CharT;
     using const_value_type = std::add_const_t<CharT>;
@@ -424,10 +422,10 @@ public:
 
     constexpr string_span_type as_string_span() const noexcept
     {
-        auto sz = span_.size();
-        return { span_.data(), sz > 1 ? sz - 1 : 0 };
+        const auto sz = span_.size();
+        return {span_.data(), sz > 1 ? sz - 1 : 0};
     }
-    constexpr string_span_type ensure_z() const noexcept { return gsl::ensure_z(span_); }
+    constexpr string_span_type ensure_z() const { return gsl::ensure_z(span_); }
 
     constexpr const_zstring_type assume_z() const noexcept { return span_.data(); }
 
@@ -464,7 +462,7 @@ template <class CharT, std::ptrdiff_t Extent, class T,
           class = std::enable_if_t<
               details::is_basic_string_span<T>::value ||
               std::is_convertible<T, gsl::basic_string_span<std::add_const_t<CharT>>>::value>>
-bool operator==(const gsl::basic_string_span<CharT, Extent>& one, const T& other) noexcept
+bool operator==(const gsl::basic_string_span<CharT, Extent>& one, const T& other)
 {
     const gsl::basic_string_span<std::add_const_t<CharT>> tmp(other);
     return std::equal(one.begin(), one.end(), tmp.begin(), tmp.end());
@@ -474,9 +472,9 @@ template <class CharT, std::ptrdiff_t Extent, class T,
           class = std::enable_if_t<
               !details::is_basic_string_span<T>::value &&
               std::is_convertible<T, gsl::basic_string_span<std::add_const_t<CharT>>>::value>>
-bool operator==(const T& one, const gsl::basic_string_span<CharT, Extent>& other) noexcept
+bool operator==(const T& one, const gsl::basic_string_span<CharT, Extent>& other)
 {
-    gsl::basic_string_span<std::add_const_t<CharT>> tmp(one);
+    const gsl::basic_string_span<std::add_const_t<CharT>> tmp(one);
     return std::equal(tmp.begin(), tmp.end(), other.begin(), other.end());
 }
 
@@ -484,7 +482,7 @@ bool operator==(const T& one, const gsl::basic_string_span<CharT, Extent>& other
 template <typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T,
           typename = std::enable_if_t<std::is_convertible<
               T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value>>
-bool operator!=(gsl::basic_string_span<CharT, Extent> one, const T& other) noexcept
+bool operator!=(gsl::basic_string_span<CharT, Extent> one, const T& other)
 {
     return !(one == other);
 }
@@ -494,7 +492,7 @@ template <
     typename = std::enable_if_t<
         std::is_convertible<T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value &&
         !gsl::details::is_basic_string_span<T>::value>>
-bool operator!=(const T& one, gsl::basic_string_span<CharT, Extent> other) noexcept
+bool operator!=(const T& one, gsl::basic_string_span<CharT, Extent> other)
 {
     return !(one == other);
 }
@@ -503,7 +501,7 @@ bool operator!=(const T& one, gsl::basic_string_span<CharT, Extent> other) noexc
 template <typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T,
           typename = std::enable_if_t<std::is_convertible<
               T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value>>
-bool operator<(gsl::basic_string_span<CharT, Extent> one, const T& other) noexcept
+bool operator<(gsl::basic_string_span<CharT, Extent> one, const T& other)
 {
     const gsl::basic_string_span<std::add_const_t<CharT>, Extent> tmp(other);
     return std::lexicographical_compare(one.begin(), one.end(), tmp.begin(), tmp.end());
@@ -514,7 +512,7 @@ template <
     typename = std::enable_if_t<
         std::is_convertible<T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value &&
         !gsl::details::is_basic_string_span<T>::value>>
-bool operator<(const T& one, gsl::basic_string_span<CharT, Extent> other) noexcept
+bool operator<(const T& one, gsl::basic_string_span<CharT, Extent> other)
 {
     gsl::basic_string_span<std::add_const_t<CharT>, Extent> tmp(one);
     return std::lexicographical_compare(tmp.begin(), tmp.end(), other.begin(), other.end());
@@ -533,7 +531,7 @@ template <
         std::is_convertible<DataType*, CharT*>::value &&
         std::is_same<std::decay_t<decltype(std::declval<T>().size(), *std::declval<T>().data())>,
                      DataType>::value>>
-bool operator<(gsl::basic_string_span<CharT, Extent> one, const T& other) noexcept
+bool operator<(gsl::basic_string_span<CharT, Extent> one, const T& other)
 {
     gsl::basic_string_span<std::add_const_t<CharT>, Extent> tmp(other);
     return std::lexicographical_compare(one.begin(), one.end(), tmp.begin(), tmp.end());
@@ -547,7 +545,7 @@ template <
         std::is_convertible<DataType*, CharT*>::value &&
         std::is_same<std::decay_t<decltype(std::declval<T>().size(), *std::declval<T>().data())>,
                      DataType>::value>>
-bool operator<(const T& one, gsl::basic_string_span<CharT, Extent> other) noexcept
+bool operator<(const T& one, gsl::basic_string_span<CharT, Extent> other)
 {
     gsl::basic_string_span<std::add_const_t<CharT>, Extent> tmp(one);
     return std::lexicographical_compare(tmp.begin(), tmp.end(), other.begin(), other.end());
@@ -558,7 +556,7 @@ bool operator<(const T& one, gsl::basic_string_span<CharT, Extent> other) noexce
 template <typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T,
           typename = std::enable_if_t<std::is_convertible<
               T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value>>
-bool operator<=(gsl::basic_string_span<CharT, Extent> one, const T& other) noexcept
+bool operator<=(gsl::basic_string_span<CharT, Extent> one, const T& other)
 {
     return !(other < one);
 }
@@ -568,7 +566,7 @@ template <
     typename = std::enable_if_t<
         std::is_convertible<T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value &&
         !gsl::details::is_basic_string_span<T>::value>>
-bool operator<=(const T& one, gsl::basic_string_span<CharT, Extent> other) noexcept
+bool operator<=(const T& one, gsl::basic_string_span<CharT, Extent> other)
 {
     return !(other < one);
 }
@@ -586,7 +584,7 @@ template <
         std::is_convertible<DataType*, CharT*>::value &&
         std::is_same<std::decay_t<decltype(std::declval<T>().size(), *std::declval<T>().data())>,
                      DataType>::value>>
-bool operator<=(gsl::basic_string_span<CharT, Extent> one, const T& other) noexcept
+bool operator<=(gsl::basic_string_span<CharT, Extent> one, const T& other)
 {
     return !(other < one);
 }
@@ -599,7 +597,7 @@ template <
         std::is_convertible<DataType*, CharT*>::value &&
         std::is_same<std::decay_t<decltype(std::declval<T>().size(), *std::declval<T>().data())>,
                      DataType>::value>>
-bool operator<=(const T& one, gsl::basic_string_span<CharT, Extent> other) noexcept
+bool operator<=(const T& one, gsl::basic_string_span<CharT, Extent> other)
 {
     return !(other < one);
 }
@@ -609,7 +607,7 @@ bool operator<=(const T& one, gsl::basic_string_span<CharT, Extent> other) noexc
 template <typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T,
           typename = std::enable_if_t<std::is_convertible<
               T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value>>
-bool operator>(gsl::basic_string_span<CharT, Extent> one, const T& other) noexcept
+bool operator>(gsl::basic_string_span<CharT, Extent> one, const T& other)
 {
     return other < one;
 }
@@ -619,7 +617,7 @@ template <
     typename = std::enable_if_t<
         std::is_convertible<T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value &&
         !gsl::details::is_basic_string_span<T>::value>>
-bool operator>(const T& one, gsl::basic_string_span<CharT, Extent> other) noexcept
+bool operator>(const T& one, gsl::basic_string_span<CharT, Extent> other)
 {
     return other < one;
 }
@@ -637,7 +635,7 @@ template <
         std::is_convertible<DataType*, CharT*>::value &&
         std::is_same<std::decay_t<decltype(std::declval<T>().size(), *std::declval<T>().data())>,
                      DataType>::value>>
-bool operator>(gsl::basic_string_span<CharT, Extent> one, const T& other) noexcept
+bool operator>(gsl::basic_string_span<CharT, Extent> one, const T& other)
 {
     return other < one;
 }
@@ -650,7 +648,7 @@ template <
         std::is_convertible<DataType*, CharT*>::value &&
         std::is_same<std::decay_t<decltype(std::declval<T>().size(), *std::declval<T>().data())>,
                      DataType>::value>>
-bool operator>(const T& one, gsl::basic_string_span<CharT, Extent> other) noexcept
+bool operator>(const T& one, gsl::basic_string_span<CharT, Extent> other)
 {
     return other < one;
 }
@@ -660,7 +658,7 @@ bool operator>(const T& one, gsl::basic_string_span<CharT, Extent> other) noexce
 template <typename CharT, std::ptrdiff_t Extent = gsl::dynamic_extent, typename T,
           typename = std::enable_if_t<std::is_convertible<
               T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value>>
-bool operator>=(gsl::basic_string_span<CharT, Extent> one, const T& other) noexcept
+bool operator>=(gsl::basic_string_span<CharT, Extent> one, const T& other)
 {
     return !(one < other);
 }
@@ -670,7 +668,7 @@ template <
     typename = std::enable_if_t<
         std::is_convertible<T, gsl::basic_string_span<std::add_const_t<CharT>, Extent>>::value &&
         !gsl::details::is_basic_string_span<T>::value>>
-bool operator>=(const T& one, gsl::basic_string_span<CharT, Extent> other) noexcept
+bool operator>=(const T& one, gsl::basic_string_span<CharT, Extent> other)
 {
     return !(one < other);
 }
@@ -688,7 +686,7 @@ template <
         std::is_convertible<DataType*, CharT*>::value &&
         std::is_same<std::decay_t<decltype(std::declval<T>().size(), *std::declval<T>().data())>,
                      DataType>::value>>
-bool operator>=(gsl::basic_string_span<CharT, Extent> one, const T& other) noexcept
+bool operator>=(gsl::basic_string_span<CharT, Extent> one, const T& other)
 {
     return !(one < other);
 }
@@ -701,7 +699,7 @@ template <
         std::is_convertible<DataType*, CharT*>::value &&
         std::is_same<std::decay_t<decltype(std::declval<T>().size(), *std::declval<T>().data())>,
                      DataType>::value>>
-bool operator>=(const T& one, gsl::basic_string_span<CharT, Extent> other) noexcept
+bool operator>=(const T& one, gsl::basic_string_span<CharT, Extent> other)
 {
     return !(one < other);
 }