Redundant code path cleanup (#1702)

Remove various obsolete configure options.
Remove Adjust SDK install tracking filth.
Remove redundant code paths in old-configure
This also optimizes linker use
Remove redundant conditional blocks.
Rewrite span.h without constexpr use.

12 files changed, 91 insertions, 297 deletions

diff --git a/build/autoconf/android.m4 b/build/autoconf/android.m4
index 4ab6d5a821..6c55a3f3f6 100644
--- a/build/autoconf/android.m4
+++ b/build/autoconf/android.m4
@@ -210,12 +210,6 @@ fi
 AC_DEFUN([MOZ_ANDROID_INSTALL_TRACKING],
 [
 
-if test -n "$MOZ_INSTALL_TRACKING"; then
-    AC_SUBST(MOZ_INSTALL_TRACKING)
-    MOZ_ANDROID_AAR(play-services-ads, $ANDROID_GOOGLE_PLAY_SERVICES_VERSION, google, com/google/android/gms)
-    MOZ_ANDROID_AAR(play-services-basement, $ANDROID_GOOGLE_PLAY_SERVICES_VERSION, google, com/google/android/gms)
-fi
-
 ])
 
 dnl Configure an Android SDK.
diff --git a/build/moz.configure/keyfiles.configure b/build/moz.configure/keyfiles.configure
index 99df5050c6..92aea5edad 100644
--- a/build/moz.configure/keyfiles.configure
+++ b/build/moz.configure/keyfiles.configure
@@ -36,10 +36,6 @@ def keyfile(desc, help=None, callback=lambda x: x):
 def simple_keyfile(desc):
     value = keyfile(desc)
     set_config('MOZ_%s_KEY' % desc.upper().replace(' ', '_'), value)
-    # Only really required for MOZ_ADJUST_SDK_KEY currently still used in
-    # old-configure.
-    add_old_configure_assignment('MOZ_%s_KEY' % desc.upper().replace(' ', '_'),
-                                 value)
 
 
 @template
diff --git a/gfx/cairo/libpixman/src/pixman.h b/gfx/cairo/libpixman/src/pixman.h
index 23408b0286..893adc50e0 100644
--- a/gfx/cairo/libpixman/src/pixman.h
+++ b/gfx/cairo/libpixman/src/pixman.h
@@ -94,16 +94,6 @@ PIXMAN_BEGIN_DECLS
 
 #if defined (_SVR4) || defined (SVR4) || defined (__OpenBSD__) || defined (_sgi) || defined (__sun) || defined (sun) || defined (__digital__) || defined (__HP_cc)
 #  include <inttypes.h>
-/* VS 2010 (_MSC_VER 1600) has stdint.h */
-#elif defined (_MSC_VER) && _MSC_VER < 1600
-typedef __int8 int8_t;
-typedef unsigned __int8 uint8_t;
-typedef __int16 int16_t;
-typedef unsigned __int16 uint16_t;
-typedef __int32 int32_t;
-typedef unsigned __int32 uint32_t;
-typedef __int64 int64_t;
-typedef unsigned __int64 uint64_t;
 #else
 #  include <stdint.h>
 #endif
diff --git a/gfx/harfbuzz/src/hb-common.h b/gfx/harfbuzz/src/hb-common.h
index 2cbee76a8f..2e17d4bb0d 100644
--- a/gfx/harfbuzz/src/hb-common.h
+++ b/gfx/harfbuzz/src/hb-common.h
@@ -51,16 +51,6 @@
 #  include <inttypes.h>
 #elif defined (_AIX)
 #  include <sys/inttypes.h>
-/* VS 2010 (_MSC_VER 1600) has stdint.h */
-#elif defined (_MSC_VER) && _MSC_VER < 1600
-typedef __int8 int8_t;
-typedef unsigned __int8 uint8_t;
-typedef __int16 int16_t;
-typedef unsigned __int16 uint16_t;
-typedef __int32 int32_t;
-typedef unsigned __int32 uint32_t;
-typedef __int64 int64_t;
-typedef unsigned __int64 uint64_t;
 #else
 #  include <stdint.h>
 #endif
diff --git a/gfx/harfbuzz/src/hb-private.hh b/gfx/harfbuzz/src/hb-private.hh
index 666af6260b..c1418d8a5d 100644
--- a/gfx/harfbuzz/src/hb-private.hh
+++ b/gfx/harfbuzz/src/hb-private.hh
@@ -178,9 +178,7 @@ static int errno = 0; /* Use something better? */
 #  elif defined(WINAPI_FAMILY) && (WINAPI_FAMILY==WINAPI_FAMILY_PC_APP || WINAPI_FAMILY==WINAPI_FAMILY_PHONE_APP)
 #    define getenv(Name) NULL
 #  endif
-#  if defined(_MSC_VER) && _MSC_VER < 1900
-#    define snprintf _snprintf
-#  elif defined(_MSC_VER) && _MSC_VER >= 1900
+#  if defined(_MSC_VER)
 #    /* Covers VC++ Error for strdup being a deprecated POSIX name and to instead use _strdup instead */
 #    define strdup _strdup
 #  endif
diff --git a/mfbt/Span.h b/mfbt/Span.h
index f031a928bb..e71e068c60 100644
--- a/mfbt/Span.h
+++ b/mfbt/Span.h
@@ -1,6 +1,7 @@
 ///////////////////////////////////////////////////////////////////////////////
 //
 // Copyright (c) 2015 Microsoft Corporation. All rights reserved.
+// Copyright (c) 2020 Moonchild Productions. All rights reserved.
 //
 // This code is licensed under the MIT License (MIT).
 //
@@ -33,15 +34,6 @@
 #include <cstring>
 #include <iterator>
 
-// Classifications for reasons why constexpr was removed in C++14 to C++11
-// conversion. Once we upgrade compilers, we can try defining each of these
-// to constexpr to restore a category of constexprs at a time.
-#define MOZ_SPAN_ASSERTION_CONSTEXPR
-#define MOZ_SPAN_GCC_CONSTEXPR
-#define MOZ_SPAN_EXPLICITLY_DEFAULTED_CONSTEXPR
-#define MOZ_SPAN_CONSTEXPR_NOT_JUST_RETURN
-#define MOZ_SPAN_NON_CONST_CONSTEXPR
-
 #ifdef _MSC_VER
 #pragma warning(push)
 
@@ -53,11 +45,6 @@
 // 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)
 
-#if _MSC_VER < 1910
-#pragma push_macro("constexpr")
-#define constexpr /*constexpr*/
-
-#endif            // _MSC_VER < 1910
 #endif            // _MSC_VER
 
 namespace mozilla {
@@ -66,7 +53,7 @@ namespace mozilla {
 
 // narrow_cast(): a searchable way to do narrowing casts of values
 template<class T, class U>
-inline constexpr T
+inline T
 narrow_cast(U&& u)
 {
   return static_cast<T>(mozilla::Forward<U>(u));
@@ -79,7 +66,7 @@ narrow_cast(U&& u)
 // and reserving a magic value that realistically doesn't occur in
 // compile-time-constant Span sizes makes things a lot less messy in terms of
 // comparison between signed and unsigned.
-constexpr const size_t dynamic_extent = mozilla::MaxValue<size_t>::value;
+const size_t dynamic_extent = mozilla::MaxValue<size_t>::value;
 
 template<class ElementType, size_t Extent = dynamic_extent>
 class Span;
@@ -157,10 +144,9 @@ public:
   using reference = conditional_t<IsConst, const element_type_, element_type_>&;
   using pointer = add_pointer_t<reference>;
 
-  constexpr span_iterator() : span_iterator(nullptr, 0) {}
+  span_iterator() : span_iterator(nullptr, 0) {}
 
-  MOZ_SPAN_ASSERTION_CONSTEXPR span_iterator(const Span* span,
-                                             typename Span::index_type index)
+  span_iterator(const Span* span, typename Span::index_type index)
     : span_(span)
     , index_(index)
   {
@@ -169,62 +155,62 @@ public:
   }
 
   friend class span_iterator<Span, true>;
-  constexpr MOZ_IMPLICIT span_iterator(const span_iterator<Span, false>& other)
+  MOZ_IMPLICIT span_iterator(const span_iterator<Span, false>& other)
     : span_iterator(other.span_, other.index_)
   {
   }
 
-  MOZ_SPAN_EXPLICITLY_DEFAULTED_CONSTEXPR span_iterator<Span, IsConst>&
+  span_iterator<Span, IsConst>&
   operator=(const span_iterator<Span, IsConst>&) = default;
 
-  MOZ_SPAN_GCC_CONSTEXPR reference operator*() const
+  reference operator*() const
   {
     MOZ_RELEASE_ASSERT(span_);
     return (*span_)[index_];
   }
 
-  MOZ_SPAN_GCC_CONSTEXPR pointer operator->() const
+  pointer operator->() const
   {
     MOZ_RELEASE_ASSERT(span_);
     return &((*span_)[index_]);
   }
 
-  MOZ_SPAN_NON_CONST_CONSTEXPR span_iterator& operator++()
+  span_iterator& operator++()
   {
     MOZ_RELEASE_ASSERT(span_ && index_ >= 0 && index_ < span_->Length());
     ++index_;
     return *this;
   }
 
-  MOZ_SPAN_NON_CONST_CONSTEXPR span_iterator operator++(int)
+  span_iterator operator++(int)
   {
     auto ret = *this;
     ++(*this);
     return ret;
   }
 
-  MOZ_SPAN_NON_CONST_CONSTEXPR span_iterator& operator--()
+  span_iterator& operator--()
   {
     MOZ_RELEASE_ASSERT(span_ && index_ > 0 && index_ <= span_->Length());
     --index_;
     return *this;
   }
 
-  MOZ_SPAN_NON_CONST_CONSTEXPR span_iterator operator--(int)
+  span_iterator operator--(int)
   {
     auto ret = *this;
     --(*this);
     return ret;
   }
 
-  MOZ_SPAN_CONSTEXPR_NOT_JUST_RETURN span_iterator
+  span_iterator
   operator+(difference_type n) const
   {
     auto ret = *this;
     return ret += n;
   }
 
-  MOZ_SPAN_GCC_CONSTEXPR span_iterator& operator+=(difference_type n)
+  span_iterator& operator+=(difference_type n)
   {
     MOZ_RELEASE_ASSERT(span_ && (index_ + n) >= 0 &&
                        (index_ + n) <= span_->Length());
@@ -232,64 +218,59 @@ public:
     return *this;
   }
 
-  MOZ_SPAN_CONSTEXPR_NOT_JUST_RETURN span_iterator
+  span_iterator
   operator-(difference_type n) const
   {
     auto ret = *this;
     return ret -= n;
   }
 
-  MOZ_SPAN_NON_CONST_CONSTEXPR span_iterator& operator-=(difference_type n)
-
+  span_iterator& operator-=(difference_type n)
   {
     return *this += -n;
   }
 
-  MOZ_SPAN_GCC_CONSTEXPR difference_type
+  difference_type
   operator-(const span_iterator& rhs) const
   {
     MOZ_RELEASE_ASSERT(span_ == rhs.span_);
     return index_ - rhs.index_;
   }
 
-  constexpr reference operator[](difference_type n) const
+  reference operator[](difference_type n) const
   {
     return *(*this + n);
   }
 
-  constexpr friend bool operator==(const span_iterator& lhs,
+  friend bool operator==(const span_iterator& lhs,
                                    const span_iterator& rhs)
   {
     return lhs.span_ == rhs.span_ && lhs.index_ == rhs.index_;
   }
 
-  constexpr friend bool operator!=(const span_iterator& lhs,
+  friend bool operator!=(const span_iterator& lhs,
                                    const span_iterator& rhs)
   {
     return !(lhs == rhs);
   }
 
-  MOZ_SPAN_GCC_CONSTEXPR friend bool operator<(const span_iterator& lhs,
-                                               const span_iterator& rhs)
+  friend bool operator<(const span_iterator& lhs, const span_iterator& rhs)
   {
     MOZ_RELEASE_ASSERT(lhs.span_ == rhs.span_);
     return lhs.index_ < rhs.index_;
   }
 
-  MOZ_SPAN_GCC_CONSTEXPR friend bool operator<=(const span_iterator& lhs,
-                                                const span_iterator& rhs)
+  friend bool operator<=(const span_iterator& lhs, const span_iterator& rhs)
   {
     return !(rhs < lhs);
   }
 
-  MOZ_SPAN_GCC_CONSTEXPR friend bool operator>(const span_iterator& lhs,
-                                               const span_iterator& rhs)
+  friend bool operator>(const span_iterator& lhs, const span_iterator& rhs)
   {
     return rhs < lhs;
   }
 
-  MOZ_SPAN_GCC_CONSTEXPR friend bool operator>=(const span_iterator& lhs,
-                                                const span_iterator& rhs)
+  friend bool operator>=(const span_iterator& lhs, const span_iterator& rhs)
   {
     return !(rhs > lhs);
   }
@@ -306,7 +287,7 @@ protected:
 };
 
 template<class Span, bool IsConst>
-inline constexpr span_iterator<Span, IsConst>
+inline span_iterator<Span, IsConst>
 operator+(typename span_iterator<Span, IsConst>::difference_type n,
           const span_iterator<Span, IsConst>& rhs)
 {
@@ -321,10 +302,10 @@ public:
 
   static_assert(Ext >= 0, "A fixed-size Span must be >= 0 in size.");
 
-  constexpr extent_type() {}
+  extent_type() {}
 
   template<index_type Other>
-  MOZ_SPAN_ASSERTION_CONSTEXPR MOZ_IMPLICIT extent_type(extent_type<Other> ext)
+  MOZ_IMPLICIT extent_type(extent_type<Other> ext)
   {
     static_assert(
       Other == Ext || Other == dynamic_extent,
@@ -332,12 +313,12 @@ public:
     MOZ_RELEASE_ASSERT(ext.size() == Ext);
   }
 
-  MOZ_SPAN_ASSERTION_CONSTEXPR MOZ_IMPLICIT extent_type(index_type length)
+  MOZ_IMPLICIT extent_type(index_type length)
   {
     MOZ_RELEASE_ASSERT(length == Ext);
   }
 
-  constexpr index_type size() const { return Ext; }
+  index_type size() const { return Ext; }
 };
 
 template<>
@@ -347,17 +328,17 @@ public:
   using index_type = size_t;
 
   template<index_type Other>
-  explicit constexpr extent_type(extent_type<Other> ext)
+  explicit extent_type(extent_type<Other> ext)
     : size_(ext.size())
   {
   }
 
-  explicit constexpr extent_type(index_type length)
+  explicit extent_type(index_type length)
     : size_(length)
   {
   }
 
-  constexpr index_type size() const { return size_; }
+  index_type size() const { return size_; }
 
 private:
   index_type size_;
@@ -442,7 +423,7 @@ public:
   using reverse_iterator = std::reverse_iterator<iterator>;
   using const_reverse_iterator = std::reverse_iterator<const_iterator>;
 
-  constexpr static const index_type extent = Extent;
+  static const index_type extent = Extent;
 
   // [Span.cons], Span constructors, copy, assignment, and destructor
   // "Dependent" is needed to make "span_details::enable_if_t<(Dependent || Extent == 0 || Extent == mozilla::MaxValue<size_t>::value)>" SFINAE,
@@ -454,7 +435,7 @@ public:
     bool Dependent = false,
     class = span_details::enable_if_t<
       (Dependent || Extent == 0 || Extent == mozilla::MaxValue<size_t>::value)>>
-  constexpr Span()
+  Span()
     : storage_(nullptr, span_details::extent_type<0>())
   {
   }
@@ -462,12 +443,12 @@ public:
   /**
    * Constructor for nullptr.
    */
-  constexpr MOZ_IMPLICIT Span(std::nullptr_t) : Span() {}
+  MOZ_IMPLICIT Span(std::nullptr_t) : Span() {}
 
   /**
    * Constructor for pointer and length.
    */
-  constexpr Span(pointer aPtr, index_type aLength)
+  Span(pointer aPtr, index_type aLength)
     : storage_(aPtr, aLength)
   {
   }
@@ -475,7 +456,7 @@ public:
   /**
    * Constructor for start pointer and pointer past end.
    */
-  constexpr Span(pointer aStartPtr, pointer aEndPtr)
+  Span(pointer aStartPtr, pointer aEndPtr)
     : storage_(aStartPtr, std::distance(aStartPtr, aEndPtr))
   {
   }
@@ -484,7 +465,7 @@ public:
    * Constructor for C array.
    */
   template<size_t N>
-  constexpr MOZ_IMPLICIT Span(element_type (&aArr)[N])
+  MOZ_IMPLICIT Span(element_type (&aArr)[N])
     : storage_(&aArr[0], span_details::extent_type<N>())
   {
   }
@@ -494,7 +475,7 @@ public:
    */
   template<size_t N,
            class ArrayElementType = span_details::remove_const_t<element_type>>
-  constexpr MOZ_IMPLICIT Span(std::array<ArrayElementType, N>& aArr)
+  MOZ_IMPLICIT Span(std::array<ArrayElementType, N>& aArr)
     : storage_(&aArr[0], span_details::extent_type<N>())
   {
   }
@@ -503,7 +484,7 @@ public:
    * Constructor for const std::array.
    */
   template<size_t N>
-  constexpr MOZ_IMPLICIT Span(
+  MOZ_IMPLICIT Span(
     const std::array<span_details::remove_const_t<element_type>, N>& aArr)
     : storage_(&aArr[0], span_details::extent_type<N>())
   {
@@ -514,7 +495,7 @@ public:
    */
   template<size_t N,
            class ArrayElementType = span_details::remove_const_t<element_type>>
-  constexpr MOZ_IMPLICIT Span(mozilla::Array<ArrayElementType, N>& aArr)
+  MOZ_IMPLICIT Span(mozilla::Array<ArrayElementType, N>& aArr)
     : storage_(&aArr[0], span_details::extent_type<N>())
   {
   }
@@ -523,7 +504,7 @@ public:
    * Constructor for const mozilla::Array.
    */
   template<size_t N>
-  constexpr MOZ_IMPLICIT Span(
+  MOZ_IMPLICIT Span(
     const mozilla::Array<span_details::remove_const_t<element_type>, N>& aArr)
     : storage_(&aArr[0], span_details::extent_type<N>())
   {
@@ -533,7 +514,7 @@ public:
    * Constructor for mozilla::UniquePtr holding an array and length.
    */
   template<class ArrayElementType = std::add_pointer<element_type>>
-  constexpr Span(const mozilla::UniquePtr<ArrayElementType>& aPtr,
+  Span(const mozilla::UniquePtr<ArrayElementType>& aPtr,
                  index_type aLength)
     : storage_(aPtr.get(), aLength)
   {
@@ -552,7 +533,7 @@ public:
       mozilla::IsConvertible<typename Container::pointer, pointer>::value &&
       mozilla::IsConvertible<typename Container::pointer,
                           decltype(mozilla::DeclVal<Container>().data())>::value>>
-  constexpr MOZ_IMPLICIT Span(Container& cont)
+  MOZ_IMPLICIT Span(Container& cont)
     : Span(cont.data(), ReleaseAssertedCast<index_type>(cont.size()))
   {
   }
@@ -568,7 +549,7 @@ public:
       mozilla::IsConvertible<typename Container::pointer, pointer>::value &&
       mozilla::IsConvertible<typename Container::pointer,
                           decltype(mozilla::DeclVal<Container>().data())>::value>>
-  constexpr MOZ_IMPLICIT Span(const Container& cont)
+  MOZ_IMPLICIT Span(const Container& cont)
     : Span(cont.data(), ReleaseAssertedCast<index_type>(cont.size()))
   {
   }
@@ -576,12 +557,12 @@ public:
   /**
    * Constructor from other Span.
    */
-  constexpr Span(const Span& other) = default;
+  Span(const Span& other) = default;
 
   /**
    * Constructor from other Span.
    */
-  constexpr Span(Span&& other) = default;
+  Span(Span&& other) = default;
 
   /**
    * Constructor from other Span with conversion of element type.
@@ -593,7 +574,7 @@ public:
       span_details::is_allowed_extent_conversion<OtherExtent, Extent>::value &&
       span_details::is_allowed_element_type_conversion<OtherElementType,
                                                        element_type>::value>>
-  constexpr MOZ_IMPLICIT Span(const Span<OtherElementType, OtherExtent>& other)
+  MOZ_IMPLICIT Span(const Span<OtherElementType, OtherExtent>& other)
     : storage_(other.data(),
                span_details::extent_type<OtherExtent>(other.size()))
   {
@@ -609,17 +590,17 @@ public:
       span_details::is_allowed_extent_conversion<OtherExtent, Extent>::value &&
       span_details::is_allowed_element_type_conversion<OtherElementType,
                                                        element_type>::value>>
-  constexpr MOZ_IMPLICIT Span(Span<OtherElementType, OtherExtent>&& other)
+  MOZ_IMPLICIT Span(Span<OtherElementType, OtherExtent>&& other)
     : storage_(other.data(),
                span_details::extent_type<OtherExtent>(other.size()))
   {
   }
 
   ~Span() = default;
-  MOZ_SPAN_EXPLICITLY_DEFAULTED_CONSTEXPR Span& operator=(const Span& other)
+  Span& operator=(const Span& other)
     = default;
 
-  MOZ_SPAN_EXPLICITLY_DEFAULTED_CONSTEXPR Span& operator=(Span&& other)
+  Span& operator=(Span&& other)
     = default;
 
   // [Span.sub], Span subviews
@@ -627,7 +608,7 @@ public:
    * Subspan with first N elements with compile-time N.
    */
   template<size_t Count>
-  MOZ_SPAN_GCC_CONSTEXPR Span<element_type, Count> First() const
+  Span<element_type, Count> First() const
   {
     MOZ_RELEASE_ASSERT(Count <= size());
     return { data(), Count };
@@ -637,7 +618,7 @@ public:
    * Subspan with last N elements with compile-time N.
    */
   template<size_t Count>
-  MOZ_SPAN_GCC_CONSTEXPR Span<element_type, Count> Last() const
+  Span<element_type, Count> Last() const
   {
     MOZ_RELEASE_ASSERT(Count <= size());
     return { data() + (size() - Count), Count };
@@ -647,7 +628,7 @@ public:
    * Subspan with compile-time start index and length.
    */
   template<size_t Offset, size_t Count = dynamic_extent>
-  MOZ_SPAN_GCC_CONSTEXPR Span<element_type, Count> Subspan() const
+  Span<element_type, Count> Subspan() const
   {
     MOZ_RELEASE_ASSERT(Offset <= size() &&
       (Count == dynamic_extent || (Offset + Count <= size())));
@@ -658,7 +639,7 @@ public:
   /**
    * Subspan with first N elements with run-time N.
    */
-  MOZ_SPAN_GCC_CONSTEXPR Span<element_type, dynamic_extent> First(
+  Span<element_type, dynamic_extent> First(
     index_type aCount) const
   {
     MOZ_RELEASE_ASSERT(aCount <= size());
@@ -668,7 +649,7 @@ public:
   /**
    * Subspan with last N elements with run-time N.
    */
-  MOZ_SPAN_GCC_CONSTEXPR Span<element_type, dynamic_extent> Last(
+  Span<element_type, dynamic_extent> Last(
     index_type aCount) const
   {
     MOZ_RELEASE_ASSERT(aCount <= size());
@@ -678,7 +659,7 @@ public:
   /**
    * Subspan with run-time start index and length.
    */
-  MOZ_SPAN_GCC_CONSTEXPR Span<element_type, dynamic_extent> Subspan(
+  Span<element_type, dynamic_extent> Subspan(
     index_type aStart,
     index_type aLength = dynamic_extent) const
   {
@@ -692,8 +673,7 @@ public:
   /**
    * Subspan with run-time start index. (Rust's &foo[start..])
    */
-  MOZ_SPAN_GCC_CONSTEXPR Span<element_type, dynamic_extent> From(
-    index_type aStart) const
+  Span<element_type, dynamic_extent> From(index_type aStart) const
   {
     return Subspan(aStart);
   }
@@ -701,8 +681,7 @@ public:
   /**
    * Subspan with run-time exclusive end index. (Rust's &foo[..end])
    */
-  MOZ_SPAN_GCC_CONSTEXPR Span<element_type, dynamic_extent> To(
-    index_type aEnd) const
+  Span<element_type, dynamic_extent> To(index_type aEnd) const
   {
     return Subspan(0, aEnd);
   }
@@ -711,9 +690,7 @@ public:
    * Subspan with run-time start index and exclusive end index.
    * (Rust's &foo[start..end])
    */
-  MOZ_SPAN_GCC_CONSTEXPR Span<element_type, dynamic_extent> FromTo(
-    index_type aStart,
-    index_type aEnd) const
+  Span<element_type, dynamic_extent> FromTo(index_type aStart, index_type aEnd) const
   {
     MOZ_RELEASE_ASSERT(aStart <= aEnd);
     return Subspan(aStart, aEnd - aStart);
@@ -723,22 +700,22 @@ public:
   /**
    * Number of elements in the span.
    */
-  constexpr index_type Length() const { return size(); }
+  index_type Length() const { return size(); }
 
   /**
    * Number of elements in the span (standard-libray duck typing version).
    */
-  constexpr index_type size() const { return storage_.size(); }
+  index_type size() const { return storage_.size(); }
 
   /**
    * Size of the span in bytes.
    */
-  constexpr index_type LengthBytes() const { return size_bytes(); }
+  index_type LengthBytes() const { return size_bytes(); }
 
   /**
    * Size of the span in bytes (standard-library naming style version).
    */
-  constexpr index_type size_bytes() const
+  index_type size_bytes() const
   {
     return size() * narrow_cast<index_type>(sizeof(element_type));
   }
@@ -746,16 +723,16 @@ public:
   /**
    * Checks if the the length of the span is zero.
    */
-  constexpr bool IsEmpty() const { return empty(); }
+  bool IsEmpty() const { return empty(); }
 
   /**
    * Checks if the the length of the span is zero (standard-libray duck
    * typing version).
    */
-  constexpr bool empty() const { return size() == 0; }
+  bool empty() const { return size() == 0; }
 
   // [Span.elem], Span element access
-  MOZ_SPAN_GCC_CONSTEXPR reference operator[](index_type idx) const
+  reference operator[](index_type idx) const
   {
     MOZ_RELEASE_ASSERT(idx < storage_.size());
     return data()[idx];
@@ -764,9 +741,9 @@ public:
   /**
    * Access element of span by index (standard-library duck typing version).
    */
-  constexpr reference at(index_type idx) const { return this->operator[](idx); }
+  reference at(index_type idx) const { return this->operator[](idx); }
 
-  constexpr reference operator()(index_type idx) const
+  reference operator()(index_type idx) const
   {
     return this->operator[](idx);
   }
@@ -774,12 +751,12 @@ public:
   /**
    * Pointer to the first element of the span.
    */
-  constexpr pointer Elements() const { return data(); }
+  pointer Elements() const { return data(); }
 
   /**
    * Pointer to the first element of the span (standard-libray duck typing version).
    */
-  constexpr pointer data() const { return storage_.data(); }
+  pointer data() const { return storage_.data(); }
 
   // [Span.iter], Span iterator support
   iterator begin() const { return { this, 0 }; }
@@ -815,8 +792,7 @@ private:
   {
   public:
     template<class OtherExtentType>
-    MOZ_SPAN_ASSERTION_CONSTEXPR storage_type(pointer elements,
-                                              OtherExtentType ext)
+    storage_type(pointer elements, OtherExtentType ext)
       : ExtentType(ext)
       , data_(elements)
     {
@@ -825,7 +801,7 @@ private:
         (elements && ExtentType::size() != mozilla::MaxValue<size_t>::value));
     }
 
-    constexpr pointer data() const { return data_; }
+    pointer data() const { return data_; }
 
   private:
     pointer data_;
@@ -836,7 +812,7 @@ private:
 
 // [Span.comparison], Span comparison operators
 template<class ElementType, size_t FirstExtent, size_t SecondExtent>
-inline constexpr bool
+inline bool
 operator==(const Span<ElementType, FirstExtent>& l,
            const Span<ElementType, SecondExtent>& r)
 {
@@ -844,7 +820,7 @@ operator==(const Span<ElementType, FirstExtent>& l,
 }
 
 template<class ElementType, size_t Extent>
-inline constexpr bool
+inline bool
 operator!=(const Span<ElementType, Extent>& l,
            const Span<ElementType, Extent>& r)
 {
@@ -852,7 +828,7 @@ operator!=(const Span<ElementType, Extent>& l,
 }
 
 template<class ElementType, size_t Extent>
-inline constexpr bool
+inline bool
 operator<(const Span<ElementType, Extent>& l,
           const Span<ElementType, Extent>& r)
 {
@@ -860,7 +836,7 @@ operator<(const Span<ElementType, Extent>& l,
 }
 
 template<class ElementType, size_t Extent>
-inline constexpr bool
+inline bool
 operator<=(const Span<ElementType, Extent>& l,
            const Span<ElementType, Extent>& r)
 {
@@ -868,7 +844,7 @@ operator<=(const Span<ElementType, Extent>& l,
 }
 
 template<class ElementType, size_t Extent>
-inline constexpr bool
+inline bool
 operator>(const Span<ElementType, Extent>& l,
           const Span<ElementType, Extent>& r)
 {
@@ -876,7 +852,7 @@ operator>(const Span<ElementType, Extent>& l,
 }
 
 template<class ElementType, size_t Extent>
-inline constexpr bool
+inline bool
 operator>=(const Span<ElementType, Extent>& l,
            const Span<ElementType, Extent>& r)
 {
@@ -884,12 +860,6 @@ operator>=(const Span<ElementType, Extent>& l,
 }
 
 namespace span_details {
-// if we only supported compilers with good constexpr support then
-// this pair of classes could collapse down to a constexpr function
-
-// we should use a narrow_cast<> to go to size_t, but older compilers may not see it as
-// constexpr
-// and so will fail compilation of the template
 template<class ElementType, size_t Extent>
 struct calculate_byte_size
   : mozilla::IntegralConstant<size_t,
@@ -1023,19 +993,7 @@ MakeCStringSpan(const char* aStr)
 } // namespace mozilla
 
 #ifdef _MSC_VER
-#if _MSC_VER < 1910
-#undef constexpr
-#pragma pop_macro("constexpr")
-
-#endif // _MSC_VER < 1910
-
 #pragma warning(pop)
 #endif // _MSC_VER
 
-#undef MOZ_SPAN_ASSERTION_CONSTEXPR
-#undef MOZ_SPAN_GCC_CONSTEXPR
-#undef MOZ_SPAN_EXPLICITLY_DEFAULTED_CONSTEXPR
-#undef MOZ_SPAN_CONSTEXPR_NOT_JUST_RETURN
-#undef MOZ_SPAN_NON_CONST_CONSTEXPR
-
 #endif // mozilla_Span_h
diff --git a/netwerk/sctp/src/netinet/sctp_os_userspace.h b/netwerk/sctp/src/netinet/sctp_os_userspace.h
index 13df424238..46d6ba9c26 100755
--- a/netwerk/sctp/src/netinet/sctp_os_userspace.h
+++ b/netwerk/sctp/src/netinet/sctp_os_userspace.h
@@ -3,6 +3,7 @@
  * Copyright (c) 2008-2011, by Randall Stewart. All rights reserved.
  * Copyright (c) 2008-2011, by Michael Tuexen. All rights reserved.
  * Copyright (c) 2008-2011, by Brad Penoff. All rights reserved.
+ * Copyright (c) 2020 by Moonchild Productions. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -49,46 +50,13 @@
 #include <Windows.h>
 #include "user_environment.h"
 typedef CRITICAL_SECTION userland_mutex_t;
-#if WINVER < 0x0600
-enum {
-	C_SIGNAL = 0,
-	C_BROADCAST = 1,
-	C_MAX_EVENTS = 2
-};
-typedef struct
-{
-	u_int waiters_count;
-	CRITICAL_SECTION waiters_count_lock;
-	HANDLE events_[C_MAX_EVENTS];
-} userland_cond_t;
-void InitializeXPConditionVariable(userland_cond_t *);
-void DeleteXPConditionVariable(userland_cond_t *);
-int SleepXPConditionVariable(userland_cond_t *, userland_mutex_t *);
-void WakeAllXPConditionVariable(userland_cond_t *);
-#define InitializeConditionVariable(cond) InitializeXPConditionVariable(cond)
-#define DeleteConditionVariable(cond) DeleteXPConditionVariable(cond)
-#define SleepConditionVariableCS(cond, mtx, time) SleepXPConditionVariable(cond, mtx)
-#define WakeAllConditionVariable(cond) WakeAllXPConditionVariable(cond)
-#else
 #define DeleteConditionVariable(cond)
 typedef CONDITION_VARIABLE userland_cond_t;
-#endif
 typedef HANDLE userland_thread_t;
 #define ADDRESS_FAMILY	unsigned __int8
 #define IPVERSION  4
 #define MAXTTL     255
-/* VS2010 comes with stdint.h */
-#if _MSC_VER >= 1600
 #include <stdint.h>
-#else
-#define uint64_t   unsigned __int64
-#define uint32_t   unsigned __int32
-#define int32_t    __int32
-#define uint16_t   unsigned __int16
-#define int16_t    __int16
-#define uint8_t    unsigned __int8
-#define int8_t     __int8
-#endif
 #ifndef _SIZE_T_DEFINED
 #define size_t     __int32
 #endif
@@ -218,9 +186,6 @@ typedef char* caddr_t;
 
 #define bzero(buf, len) memset(buf, 0, len)
 #define bcopy(srcKey, dstKey, len) memcpy(dstKey, srcKey, len)
-#if _MSC_VER < 1900
-#define snprintf(data, size, format, ...) _snprintf_s(data, size, _TRUNCATE, format, __VA_ARGS__)
-#endif
 #define inline __inline
 #define __inline__ __inline
 #define	MSG_EOR		0x8		/* data completes record */
diff --git a/old-configure.in b/old-configure.in
index ade675e956..c06687f145 100644
--- a/old-configure.in
+++ b/old-configure.in
@@ -961,16 +961,10 @@ case "$target" in
             CXXFLAGS="$CXXFLAGS -utf-8"
         fi
         if test "$CPU_ARCH" = "x86"; then
-            dnl VS2012+ defaults to -arch:SSE2. We want to target nothing
-            dnl more recent, so set that explicitly here unless another
-            dnl target arch has already been set.
             changequote(,)
-            if test -z `echo $CFLAGS | grep -i [-/]arch:`; then
-              CFLAGS="$CFLAGS -arch:SSE2"
-            fi
-            if test -z `echo $CXXFLAGS | grep -i [-/]arch:`; then
-              CXXFLAGS="$CXXFLAGS -arch:SSE2"
-            fi
+            dnl VS2012+ defaults to -arch:SSE2. We want to target nothing
+            dnl more recent, so no need to set it explicitly in the default
+            dnl case.
             changequote([,])
             SSE_FLAGS="-arch:SSE"
             SSE2_FLAGS="-arch:SSE2"
@@ -1086,15 +1080,15 @@ case "$target" in
         WARNINGS_AS_ERRORS='-WX'
         MOZ_OPTIMIZE_FLAGS='-O1 -Oi'
         MOZ_FIX_LINK_PATHS=
-        LDFLAGS="$LDFLAGS -LARGEADDRESSAWARE -NXCOMPAT"
+        num_cores=$($PYTHON -c 'import multiprocessing; print(min(8,multiprocessing.cpu_count()))')
+        cgthreads="-CGTHREADS:${num_cores}"
+        LDFLAGS="$LDFLAGS -LARGEADDRESSAWARE -NXCOMPAT -DYNAMICBASE -OPT:REF -OPT:ICF=${num_cores} $cgthreads"
         if test -z "$DEVELOPER_OPTIONS"; then
             LDFLAGS="$LDFLAGS -RELEASE"
         fi
         dnl For profile-guided optimization
         PROFILE_GEN_CFLAGS="-GL"
-        num_cores=$($PYTHON -c 'import multiprocessing; print(min(8,multiprocessing.cpu_count()))')
-        cgthreads="-CGTHREADS:${num_cores}"
-        PROFILE_GEN_LDFLAGS="-LTCG:PGINSTRUMENT -PogoSafeMode $cgthreads"
+        PROFILE_GEN_LDFLAGS="-LTCG:PGINSTRUMENT"
         dnl XXX: PGO builds can fail with warnings treated as errors,
         dnl specifically "no profile data available" appears to be
         dnl treated as an error sometimes. This might be a consequence
@@ -1105,19 +1099,11 @@ case "$target" in
         PROFILE_USE_CFLAGS="-GL -wd4624 -wd4952"
         dnl XXX: should be -LTCG:PGOPTIMIZE, but that fails on libxul.
         dnl Probably also a compiler bug, but what can you do?
-        PROFILE_USE_LDFLAGS="-LTCG:PGUPDATE $cgthreads"
-        LDFLAGS="$LDFLAGS -DYNAMICBASE"
+        PROFILE_USE_LDFLAGS="-LTCG:PGUPDATE"
         RCFLAGS="-nologo"
-        if test "$CC_VERSION" = "18.00.31101"; then
-            dnl Use MaxILKSize as a workaround for LNK1248 in VS2013update4
-            dnl See https://connect.microsoft.com/VisualStudio/feedback/details/1044914/fatal-error-lnk1248
-            LDFLAGS="$LDFLAGS -MaxILKSize:0x7FF00000"
-        fi
-        dnl Minimum reqiurement of Gecko is VS2010 or later which supports
-        dnl both SSSE3 and SSE4.1.
+        dnl Minimum required VS version supports SSSE3, SSE4.1 and AVX2.
         HAVE_TOOLCHAIN_SUPPORT_MSSSE3=1
         HAVE_TOOLCHAIN_SUPPORT_MSSE4_1=1
-        dnl allow AVX2 code from VS2012
         HAVE_X86_AVX2=1
     fi
     AC_DEFINE(WIN32_LEAN_AND_MEAN)
@@ -2149,7 +2135,6 @@ MOZ_NECKO_WIFI=1
 NECKO_COOKIES=1
 MOZ_USE_NATIVE_POPUP_WINDOWS=
 MOZ_EXCLUDE_HYPHENATION_DICTIONARIES=
-MOZ_INSTALL_TRACKING=
 ACCESSIBILITY=1
 MOZ_TIME_MANAGER=
 MOZ_AUDIO_CHANNEL_MANAGER=
@@ -2185,22 +2170,6 @@ case "${target}" in
 
 esac
 
-# Optional Firefox for Android partner distribution directory.
-MOZ_ARG_WITH_STRING(android-distribution-directory,
-[  --with-android-distribution-directory=dir
-                          Optional Firefox for Android partner distribution directory.],
-  MOZ_ANDROID_DISTRIBUTION_DIRECTORY=$withval)
-
-if test -n "$MOZ_ANDROID_DISTRIBUTION_DIRECTORY"; then
-  # A distribution directory must have an assets/distribution directory.
-  # See https://wiki.mozilla.org/Mobile/Distribution_Files.
-  if test ! -d "$MOZ_ANDROID_DISTRIBUTION_DIRECTORY/assets/distribution" ; then
-    AC_MSG_ERROR([--with-android-distribution-directory does not contain assets/distribution;
-                  (looked for ${MOZ_ANDROID_DISTRIBUTION_DIRECTORY}/assets/distribution).])
-  fi
-fi
-AC_SUBST(MOZ_ANDROID_DISTRIBUTION_DIRECTORY)
-
 dnl ========================================================
 dnl = Vendor override
 dnl ========================================================
@@ -2250,11 +2219,6 @@ if test -n "$WITH_APP_BASENAME" ; then
     MOZ_APP_BASENAME="$WITH_APP_BASENAME"
 fi
 
-# Graphene is a desktop runtime for running applications with a HTML UI.
-if test -n "$MOZ_GRAPHENE"; then
-    AC_DEFINE(MOZ_GRAPHENE)
-fi
-
 dnl ========================================================
 dnl Ensure Android SDK and build-tools versions depending on
 dnl mobile target.
@@ -2633,15 +2597,6 @@ if test -n "$MOZ_EXCLUDE_HYPHENATION_DICTIONARIES"; then
 fi
 
 dnl ========================================================
-dnl = Include install tracking on Android
-dnl ========================================================
-if test -n "$MOZ_INSTALL_TRACKING"; then
-    if test -z "$MOZ_ADJUST_SDK_KEY"; then
-        AC_MSG_ERROR([Must specify --with-adjust-sdk-keyfile when MOZ_INSTALL_TRACKING is defined!])
-    fi
-fi
-
-dnl ========================================================
 dnl accessibility support on by default on all platforms
 dnl ========================================================
 MOZ_ARG_DISABLE_BOOL(accessibility,
@@ -4994,7 +4949,6 @@ AC_SUBST(MOZ_ANDROID_APPLICATION_CLASS)
 AC_SUBST(MOZ_ANDROID_BROWSER_INTENT_CLASS)
 AC_SUBST(MOZ_ANDROID_SEARCH_INTENT_CLASS)
 AC_SUBST(MOZ_EXCLUDE_HYPHENATION_DICTIONARIES)
-AC_SUBST(MOZ_INSTALL_TRACKING)
 AC_SUBST(ENABLE_STRIP)
 AC_SUBST(PKG_SKIP_STRIP)
 AC_SUBST(STRIP_FLAGS)
diff --git a/parser/expat/lib/expat_external.h b/parser/expat/lib/expat_external.h
index 70c630bc92..cb046cfc0f 100644
--- a/parser/expat/lib/expat_external.h
+++ b/parser/expat/lib/expat_external.h
@@ -102,13 +102,8 @@ typedef char XML_LChar;
 /* END MOZILLA CHANGE */
 
 #ifdef XML_LARGE_SIZE  /* Use large integers for file/stream positions. */
-#if defined(XML_USE_MSC_EXTENSIONS) && _MSC_VER < 1400
-typedef __int64 XML_Index; 
-typedef unsigned __int64 XML_Size;
-#else
 typedef long long XML_Index;
 typedef unsigned long long XML_Size;
-#endif
 #else
 typedef long XML_Index;
 typedef unsigned long XML_Size;
diff --git a/toolkit/content/license.html b/toolkit/content/license.html
index 1041ec42f6..d97a3c7f1e 100644
--- a/toolkit/content/license.html
+++ b/toolkit/content/license.html
@@ -67,9 +67,6 @@
       </li>
       <li><a href="about:license#ACE">ACE License</a></li>
       <li><a href="about:license#acorn">acorn License</a></li>
-#ifdef MOZ_INSTALL_TRACKING
-      <li><a href="about:license#adjust">Adjust SDK License</a></li>
-#endif
       <li><a href="about:license#adobecmap">Adobe CMap License</a></li>
       <li><a href="about:license#android">Android Open Source License</a></li>
       <li><a href="about:license#angle">ANGLE License</a></li>
@@ -2233,39 +2230,6 @@ licences.
 
     <hr>
 
-#ifdef MOZ_INSTALL_TRACKING
-    <h1><a id="adjust"></a>Adjust SDK License</h1>
-
-    <p>This license applies to all files in the directory
-    <span class="path">mobile/android/thirdparty/com/adjust/sdk</span>.</p>
-
-<pre>
-Copyright (c) 2012-2014 adjust GmbH,
-http://www.adjust.com
-
-Permission is hereby granted, free of charge, to any person obtaining
-a copy of this software and associated documentation files (the
-"Software"), to deal in the Software without restriction, including
-without limitation the rights to use, copy, modify, merge, publish,
-distribute, sublicense, and/or sell copies of the Software, and to
-permit persons to whom the Software is furnished to do so, subject to
-the following conditions:
-
-The above copyright notice and this permission notice shall be
-included in all copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
-LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-</pre>
-
-    <hr>
-
-#endif
     <h1><a id="apache"></a>Apache License 2.0</h1>
 
     <p>This license applies to various files in the Mozilla codebase.</p>
diff --git a/toolkit/modules/AppConstants.jsm b/toolkit/modules/AppConstants.jsm
index 5eea04b0fb..889a38b931 100644
--- a/toolkit/modules/AppConstants.jsm
+++ b/toolkit/modules/AppConstants.jsm
@@ -180,13 +180,6 @@ MOZ_SAFE_BROWSING:
   false,
 #endif
 
-  MOZ_GRAPHENE:
-#ifdef MOZ_GRAPHENE
-  true,
-#else
-  false,
-#endif
-
   MOZ_PLACES:
 #ifdef MOZ_PLACES
   true,
diff --git a/toolkit/mozapps/update/common/updatedefines.h b/toolkit/mozapps/update/common/updatedefines.h
index 871755246c..49fbde6f2f 100644
--- a/toolkit/mozapps/update/common/updatedefines.h
+++ b/toolkit/mozapps/update/common/updatedefines.h
@@ -44,9 +44,6 @@
 # define access _access
 
 # define putenv _putenv
-# if defined(_MSC_VER) && _MSC_VER < 1900
-#  define stat _stat
-# endif
 # define DELETE_DIR L"tobedeleted"
 # define CALLBACK_BACKUP_EXT L".moz-callback"