Userland: static vs non-static constexpr variables

Problem:
- `static` variables consume memory and sometimes are less
  optimizable.
- `static const` variables can be `constexpr`, usually.
- `static` function-local variables require an initialization check
  every time the function is run.

Solution:
- If a global `static` variable is only used in a single function then
  move it into the function and make it non-`static` and `constexpr`.
- Make all global `static` variables `constexpr` instead of `const`.
- Change function-local `static const[expr]` variables to be just
  `constexpr`.

Userland/Applications/Browser/CookieJar.cpp

@@ -7,6 +7,7 @@
 #include "CookieJar.h"
 #include <AK/IPv4Address.h>
 #include <AK/StringBuilder.h>
+#include <AK/StringView.h>
 #include <AK/URL.h>
 #include <AK/Vector.h>
 #include <LibWeb/Cookie/ParsedCookie.h>
@@ -48,9 +49,9 @@ void CookieJar::set_cookie(const URL& url, const Web::Cookie::ParsedCookie& pars
 
 void CookieJar::dump_cookies() const
 {
-    static const char* key_color = "\033[34;1m";
-    static const char* attribute_color = "\033[33m";
-    static const char* no_color = "\033[0m";
+    constexpr StringView key_color = "\033[34;1m";
+    constexpr StringView attribute_color = "\033[33m";
+    constexpr StringView no_color = "\033[0m";
 
     StringBuilder builder;
     builder.appendff("{} cookies stored\n", m_cookies.size());

Userland/Applications/Calendar/AddEventDialog.cpp

@@ -5,6 +5,7 @@
  */
 
 #include "AddEventDialog.h"
+#include <AK/StringView.h>
 #include <LibCore/DateTime.h>
 #include <LibGUI/BoxLayout.h>
 #include <LibGUI/Button.h>
@@ -20,11 +21,6 @@
 #include <LibGfx/Font.h>
 #include <LibGfx/FontDatabase.h>
 
-static const char* short_month_names[] = {
-    "Jan", "Feb", "Mar", "Apr", "May", "Jun",
-    "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
-};
-
 AddEventDialog::AddEventDialog(Core::DateTime date_time, Window* parent_window)
     : Dialog(parent_window)
     , m_date_time(date_time)
@@ -121,6 +117,11 @@ String AddEventDialog::MonthListModel::column_name(int column) const
 
 GUI::Variant AddEventDialog::MonthListModel::data(const GUI::ModelIndex& index, GUI::ModelRole role) const
 {
+    constexpr StringView short_month_names[] = {
+        "Jan", "Feb", "Mar", "Apr", "May", "Jun",
+        "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
+    };
+
     auto& month = short_month_names[index.row()];
     if (role == GUI::ModelRole::Display) {
         switch (index.column()) {

Userland/Applications/FontEditor/FontEditor.cpp

@@ -9,6 +9,7 @@
 #include "GlyphMapWidget.h"
 #include "NewFontDialog.h"
 #include <AK/StringBuilder.h>
+#include <AK/StringView.h>
 #include <AK/UnicodeUtils.h>
 #include <Applications/FontEditor/FontEditorWindowGML.h>
 #include <LibDesktop/Launcher.h>
@@ -37,19 +38,19 @@
 #include <LibGfx/TextDirection.h>
 #include <stdlib.h>
 
-static constexpr int s_pangram_count = 7;
-static const char* pangrams[s_pangram_count] = {
-    "quick fox jumps nightly above wizard",
-    "five quacking zephyrs jolt my wax bed",
-    "pack my box with five dozen liquor jugs",
-    "quick brown fox jumps over the lazy dog",
-    "waxy and quivering jocks fumble the pizza",
-    "~#:[@_1%]*{$2.3}/4^(5'6\")-&|7+8!=<9,0\\>?;",
-    "byxfjärmat föl gick på duvshowen"
-};
-
 static RefPtr<GUI::Window> create_font_preview_window(FontEditorWidget& editor)
 {
+    constexpr int pangram_count = 7;
+    constexpr StringView pangrams[pangram_count] = {
+        "quick fox jumps nightly above wizard",
+        "five quacking zephyrs jolt my wax bed",
+        "pack my box with five dozen liquor jugs",
+        "quick brown fox jumps over the lazy dog",
+        "waxy and quivering jocks fumble the pizza",
+        "~#:[@_1%]*{$2.3}/4^(5'6\")-&|7+8!=<9,0\\>?;",
+        "byxfjärmat föl gick på duvshowen"
+    };
+
     auto window = GUI::Window::construct();
     window->set_window_type(GUI::WindowType::ToolWindow);
     window->set_title("Font preview");
@@ -94,7 +95,7 @@ static RefPtr<GUI::Window> create_font_preview_window(FontEditorWidget& editor)
     reload_button.set_fixed_width(22);
     reload_button.on_click = [&] {
         static int i = 1;
-        if (i >= s_pangram_count)
+        if (i >= pangram_count)
             i = 0;
         preview_textbox.set_text(pangrams[i]);
         i++;

Userland/Applications/HexEditor/FindDialog.cpp

@@ -5,9 +5,9 @@
  */
 
 #include "FindDialog.h"
+#include <AK/Array.h>
 #include <AK/Hex.h>
 #include <AK/String.h>
-#include <AK/Vector.h>
 #include <LibGUI/BoxLayout.h>
 #include <LibGUI/Button.h>
 #include <LibGUI/Label.h>
@@ -19,17 +19,12 @@
 #include <LibGfx/FontDatabase.h>
 
 struct Option {
-    String title;
+    StringView title;
     OptionId opt;
     bool enabled;
     bool default_action;
 };
 
-static const Vector<Option> options = {
-    { "ACII String", OPTION_ASCII_STRING, true, true },
-    { "Hex value", OPTION_HEX_VALUE, true, false },
-};
-
 int FindDialog::show(GUI::Window* parent_window, String& out_text, ByteBuffer& out_buffer)
 {
     auto dialog = FindDialog::construct();
@@ -88,6 +83,11 @@ Result<ByteBuffer, String> FindDialog::process_input(String text_value, OptionId
 FindDialog::FindDialog()
     : Dialog(nullptr)
 {
+    constexpr Array options = {
+        Option { "ACII String", OPTION_ASCII_STRING, true, true },
+        Option { "Hex value", OPTION_HEX_VALUE, true, false },
+    };
+
     resize(280, 180 + ((static_cast<int>(options.size()) - 3) * 16));
     center_on_screen();
     set_resizable(false);
@@ -113,7 +113,7 @@ FindDialog::FindDialog()
         radio.set_enabled(action.enabled);
         radio.set_text(action.title);
 
-        radio.on_checked = [this, i](auto) {
+        radio.on_checked = [&](auto) {
             m_selected_option = options[i].opt;
         };
 

Userland/Applications/SpaceAnalyzer/TreeMapWidget.cpp

@@ -5,6 +5,7 @@
  */
 
 #include "TreeMapWidget.h"
+#include <AK/Array.h>
 #include <AK/NumberFormat.h>
 #include <LibGUI/Painter.h>
 #include <LibGUI/WindowServerConnection.h>
@@ -24,7 +25,7 @@ TreeMapWidget::~TreeMapWidget()
 {
 }
 
-static const Color colors[] = {
+static constexpr Array colors = {
     Color(253, 231, 37),
     Color(148, 216, 64),
     Color(60, 188, 117),

Userland/Applications/SpaceAnalyzer/main.cpp

@@ -9,6 +9,7 @@
 #include <AK/Queue.h>
 #include <AK/QuickSort.h>
 #include <AK/RefCounted.h>
+#include <AK/StringView.h>
 #include <AK/URL.h>
 #include <Applications/SpaceAnalyzer/SpaceAnalyzerGML.h>
 #include <LibCore/DirIterator.h>
@@ -27,8 +28,6 @@
 #include <sys/stat.h>
 #include <unistd.h>
 
-static const char* APP_NAME = "Space Analyzer";
-
 struct TreeNode : public SpaceAnalyzer::TreeMapNode {
     TreeNode(String name)
         : m_name(move(name)) {};
@@ -253,6 +252,8 @@ static String get_absolute_path_to_selected_node(const SpaceAnalyzer::TreeMapWid
 
 int main(int argc, char* argv[])
 {
+    constexpr StringView APP_NAME = "Space Analyzer";
+
     auto app = GUI::Application::construct(argc, argv);
 
     RefPtr<Tree> tree = adopt_ref(*new Tree(""));

Userland/Demos/Fire/Fire.cpp

@@ -22,6 +22,7 @@
  *  [ ] handle fire bitmap edges better
 */
 
+#include <AK/Array.h>
 #include <LibCore/ElapsedTimer.h>
 #include <LibGUI/Action.h>
 #include <LibGUI/Application.h>
@@ -38,22 +39,9 @@
 #include <time.h>
 #include <unistd.h>
 
-#define FIRE_WIDTH 320
-#define FIRE_HEIGHT 168
-#define FIRE_MAX 29
-
-static const Color s_palette[] = {
-    Color(0x07, 0x07, 0x07), Color(0x1F, 0x07, 0x07), Color(0x2F, 0x0F, 0x07),
-    Color(0x47, 0x0F, 0x07), Color(0x57, 0x17, 0x07), Color(0x67, 0x1F, 0x07),
-    Color(0x77, 0x1F, 0x07), Color(0x9F, 0x2F, 0x07), Color(0xAF, 0x3F, 0x07),
-    Color(0xBF, 0x47, 0x07), Color(0xC7, 0x47, 0x07), Color(0xDF, 0x4F, 0x07),
-    Color(0xDF, 0x57, 0x07), Color(0xD7, 0x5F, 0x07), Color(0xD7, 0x5F, 0x07),
-    Color(0xD7, 0x67, 0x0F), Color(0xCF, 0x6F, 0x0F), Color(0xCF, 0x7F, 0x0F),
-    Color(0xCF, 0x87, 0x17), Color(0xC7, 0x87, 0x17), Color(0xC7, 0x8F, 0x17),
-    Color(0xC7, 0x97, 0x1F), Color(0xBF, 0x9F, 0x1F), Color(0xBF, 0xA7, 0x27),
-    Color(0xBF, 0xAF, 0x2F), Color(0xB7, 0xAF, 0x2F), Color(0xB7, 0xB7, 0x37),
-    Color(0xCF, 0xCF, 0x6F), Color(0xEF, 0xEF, 0xC7), Color(0xFF, 0xFF, 0xFF)
-};
+static constexpr auto FIRE_WIDTH = 320;
+static constexpr auto FIRE_HEIGHT = 168;
+static constexpr auto FIRE_MAX = 29;
 
 class Fire : public GUI::Widget {
     C_OBJECT(Fire)
@@ -80,11 +68,24 @@ private:
 
 Fire::Fire()
 {
+    constexpr Array palette = {
+        Color(0x07, 0x07, 0x07), Color(0x1F, 0x07, 0x07), Color(0x2F, 0x0F, 0x07),
+        Color(0x47, 0x0F, 0x07), Color(0x57, 0x17, 0x07), Color(0x67, 0x1F, 0x07),
+        Color(0x77, 0x1F, 0x07), Color(0x9F, 0x2F, 0x07), Color(0xAF, 0x3F, 0x07),
+        Color(0xBF, 0x47, 0x07), Color(0xC7, 0x47, 0x07), Color(0xDF, 0x4F, 0x07),
+        Color(0xDF, 0x57, 0x07), Color(0xD7, 0x5F, 0x07), Color(0xD7, 0x5F, 0x07),
+        Color(0xD7, 0x67, 0x0F), Color(0xCF, 0x6F, 0x0F), Color(0xCF, 0x7F, 0x0F),
+        Color(0xCF, 0x87, 0x17), Color(0xC7, 0x87, 0x17), Color(0xC7, 0x8F, 0x17),
+        Color(0xC7, 0x97, 0x1F), Color(0xBF, 0x9F, 0x1F), Color(0xBF, 0xA7, 0x27),
+        Color(0xBF, 0xAF, 0x2F), Color(0xB7, 0xAF, 0x2F), Color(0xB7, 0xB7, 0x37),
+        Color(0xCF, 0xCF, 0x6F), Color(0xEF, 0xEF, 0xC7), Color(0xFF, 0xFF, 0xFF)
+    };
+
     bitmap = Gfx::Bitmap::create(Gfx::BitmapFormat::Indexed8, { 320, 200 });
 
     /* Initialize fire palette */
     for (int i = 0; i < 30; i++)
-        bitmap->set_palette_color(i, s_palette[i]);
+        bitmap->set_palette_color(i, palette[i]);
 
     /* Set remaining entries to white */
     for (int i = 30; i < 256; i++)

Userland/Games/Breakout/Game.h

@@ -14,8 +14,8 @@ class Game final : public GUI::Widget {
     C_OBJECT(Game);
 
 public:
-    static const int game_width = 480;
-    static const int game_height = 500;
+    static constexpr int game_width = 480;
+    static constexpr int game_height = 500;
 
     virtual ~Game() override;
 

Userland/Games/Pong/Game.h

@@ -22,8 +22,8 @@ class Game final : public GUI::Widget {
     C_OBJECT(Game);
 
 public:
-    static const int game_width = 560;
-    static const int game_height = 480;
+    static constexpr int game_width = 560;
+    static constexpr int game_height = 480;
 
     virtual ~Game() override;
 

Userland/Libraries/LibC/netdb.cpp

@@ -36,7 +36,7 @@ static constexpr i32 lookup_server_endpoint_magic = 9001;
 
 // Get service entry buffers and file information for the getservent() family of functions.
 static FILE* services_file = nullptr;
-static const char* services_path = "/etc/services";
+static constexpr char services_path[] = "/etc/services";
 
 static bool fill_getserv_buffers(const char* line, ssize_t read);
 static servent __getserv_buffer;
@@ -50,7 +50,7 @@ static ssize_t service_file_offset = 0;
 
 // Get protocol entry buffers and file information for the getprotent() family of functions.
 static FILE* protocols_file = nullptr;
-static const char* protocols_path = "/etc/protocols";
+static constexpr char protocols_path[] = "/etc/protocols";
 
 static bool fill_getproto_buffers(const char* line, ssize_t read);
 static protoent __getproto_buffer;

Userland/Libraries/LibC/time.cpp

@@ -70,10 +70,9 @@ char* ctime_r(const time_t* t, char* buf)
     return asctime_r(localtime_r(t, &tm_buf), buf);
 }
 
-static const int __seconds_per_day = 60 * 60 * 24;
-
 static void time_to_tm(struct tm* tm, time_t t)
 {
+    constexpr int __seconds_per_day = 60 * 60 * 24;
     int year = 1970;
     for (; t >= days_in_year(year) * __seconds_per_day; ++year)
         t -= days_in_year(year) * __seconds_per_day;

Userland/Libraries/LibGUI/Calendar.cpp

@@ -5,6 +5,7 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <AK/Array.h>
 #include <LibCore/DateTime.h>
 #include <LibGUI/Calendar.h>
 #include <LibGUI/Painter.h>
@@ -16,21 +17,21 @@ REGISTER_WIDGET(GUI, Calendar);
 
 namespace GUI {
 
-static const char* long_day_names[] = {
+static constexpr Array long_day_names = {
     "Sunday", "Monday", "Tuesday", "Wednesday",
     "Thursday", "Friday", "Saturday"
 };
 
-static const char* short_day_names[] = { "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" };
-static const char* mini_day_names[] = { "Su", "Mo", "Tu", "We", "Th", "Fr", "Sa" };
-static const char* micro_day_names[] = { "S", "M", "T", "W", "T", "F", "S" };
+static constexpr Array short_day_names = { "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" };
+static constexpr Array mini_day_names = { "Su", "Mo", "Tu", "We", "Th", "Fr", "Sa" };
+static constexpr Array micro_day_names = { "S", "M", "T", "W", "T", "F", "S" };
 
-static const char* long_month_names[] = {
+static constexpr Array long_month_names = {
     "January", "February", "March", "April", "May", "June",
     "July", "August", "September", "October", "November", "December"
 };
 
-static const char* short_month_names[] = {
+static constexpr Array short_month_names = {
     "Jan", "Feb", "Mar", "Apr", "May", "Jun",
     "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
 };

Userland/Libraries/LibGUI/CheckBox.cpp

@@ -15,9 +15,9 @@ REGISTER_WIDGET(GUI, CheckBox)
 
 namespace GUI {
 
-static const int s_box_width = 13;
-static const int s_box_height = 13;
-static const int s_horizontal_padding = 6;
+static constexpr int s_box_width = 13;
+static constexpr int s_box_height = 13;
+static constexpr int s_horizontal_padding = 6;
 
 CheckBox::CheckBox(String text)
     : AbstractButton(move(text))

Userland/Libraries/LibGUI/ColumnsView.cpp

@@ -13,7 +13,7 @@
 
 namespace GUI {
 
-static const char* s_arrow_bitmap_data = {
+static constexpr char s_arrow_bitmap_data[] = {
     "         "
     "   #     "
     "   ##    "
@@ -24,8 +24,8 @@ static const char* s_arrow_bitmap_data = {
     "   #     "
     "         "
 };
-static const int s_arrow_bitmap_width = 9;
-static const int s_arrow_bitmap_height = 9;
+static constexpr int s_arrow_bitmap_width = 9;
+static constexpr int s_arrow_bitmap_height = 9;
 
 ColumnsView::ColumnsView()
 {

Userland/Libraries/LibGUI/FileIconProvider.cpp

@@ -169,7 +169,10 @@ Icon FileIconProvider::icon_for_executable(const String& path)
         int image_size;
     };
 
-    static const IconSection icon_sections[] = { { .section_name = "serenity_icon_s", .image_size = 16 }, { .section_name = "serenity_icon_m", .image_size = 32 } };
+    constexpr Array icon_sections = {
+        IconSection { .section_name = "serenity_icon_s", .image_size = 16 },
+        IconSection { .section_name = "serenity_icon_m", .image_size = 32 }
+    };
 
     bool had_error = false;
     for (const auto& icon_section : icon_sections) {

Userland/Libraries/LibGUI/ResizeCorner.cpp

@@ -12,7 +12,7 @@
 
 namespace GUI {
 
-static const char* s_resize_corner_shadows_data = {
+static constexpr char s_resize_corner_shadows_data[] = {
     "                "
     "             ## "
     "             #  "
@@ -31,7 +31,7 @@ static const char* s_resize_corner_shadows_data = {
     "                "
 };
 
-static const char* s_resize_corner_highlights_data = {
+static constexpr char s_resize_corner_highlights_data[] = {
     "                "
     "                "
     "              # "
@@ -52,8 +52,8 @@ static const char* s_resize_corner_highlights_data = {
 
 static Gfx::CharacterBitmap* s_resize_corner_shadows_bitmap;
 static Gfx::CharacterBitmap* s_resize_corner_highlights_bitmap;
-static const int s_resize_corner_bitmap_width = 16;
-static const int s_resize_corner_bitmap_height = 16;
+static constexpr int s_resize_corner_bitmap_width = 16;
+static constexpr int s_resize_corner_bitmap_height = 16;
 
 ResizeCorner::ResizeCorner()
 {

Userland/Libraries/LibGUI/Scrollbar.cpp

@@ -15,7 +15,7 @@ REGISTER_WIDGET(GUI, Scrollbar)
 
 namespace GUI {
 
-static const char* s_up_arrow_bitmap_data = {
+static constexpr char s_up_arrow_bitmap_data[] = {
     "         "
     "    #    "
     "   ###   "
@@ -27,7 +27,7 @@ static const char* s_up_arrow_bitmap_data = {
     "         "
 };
 
-static const char* s_down_arrow_bitmap_data = {
+static constexpr char s_down_arrow_bitmap_data[] = {
     "         "
     "   ###   "
     "   ###   "
@@ -39,7 +39,7 @@ static const char* s_down_arrow_bitmap_data = {
     "         "
 };
 
-static const char* s_left_arrow_bitmap_data = {
+static constexpr char s_left_arrow_bitmap_data[] = {
     "         "
     "    #    "
     "   ##    "
@@ -51,7 +51,7 @@ static const char* s_left_arrow_bitmap_data = {
     "         "
 };
 
-static const char* s_right_arrow_bitmap_data = {
+static constexpr char s_right_arrow_bitmap_data[] = {
     "         "
     "    #    "
     "    ##   "

Userland/Libraries/LibGfx/ClassicStylePainter.cpp

@@ -354,7 +354,7 @@ void ClassicStylePainter::paint_radio_button(Painter& painter, const IntRect& re
     painter.blit(rect.location(), bitmap, bitmap.rect());
 }
 
-static const char* s_checked_bitmap_data = {
+static constexpr char s_checked_bitmap_data[] = {
     "         "
     "       # "
     "      ## "
@@ -367,8 +367,8 @@ static const char* s_checked_bitmap_data = {
 };
 
 static Gfx::CharacterBitmap* s_checked_bitmap;
-static const int s_checked_bitmap_width = 9;
-static const int s_checked_bitmap_height = 9;
+static constexpr int s_checked_bitmap_width = 9;
+static constexpr int s_checked_bitmap_height = 9;
 
 void ClassicStylePainter::paint_check_box(Painter& painter, const IntRect& rect, const Palette& palette, bool is_enabled, bool is_checked, bool is_being_pressed)
 {

Userland/Libraries/LibGfx/Color.h

@@ -140,7 +140,7 @@ public:
 #endif
     }
 
-    constexpr Color interpolate(const Color& other, float weight) const
+    Color interpolate(const Color& other, float weight) const
     {
         u8 r = red() + roundf(static_cast<float>(other.red() - red()) * weight);
         u8 g = green() + roundf(static_cast<float>(other.green() - green()) * weight);

Userland/Libraries/LibGfx/GIFLoader.cpp

@@ -19,10 +19,6 @@
 
 namespace Gfx {
 
-// Row strides and offsets for each interlace pass.
-static const int INTERLACE_ROW_STRIDES[] = { 8, 8, 4, 2 };
-static const int INTERLACE_ROW_OFFSETS[] = { 0, 4, 2, 1 };
-
 struct ImageDescriptor {
     u16 x { 0 };
     u16 y { 0 };
@@ -112,8 +108,8 @@ enum class GIFFormat {
 
 static Optional<GIFFormat> decode_gif_header(InputMemoryStream& stream)
 {
-    static const char valid_header_87[] = "GIF87a";
-    static const char valid_header_89[] = "GIF89a";
+    constexpr char valid_header_87[] = "GIF87a";
+    constexpr char valid_header_89[] = "GIF89a";
 
     Array<u8, 6> header;
     stream >> header;
@@ -378,6 +374,8 @@ static bool decode_frame(GIFLoadingContext& context, size_t frame_index)
                 if (pixel_index % image.width == 0) {
                     if (image.interlaced) {
                         if (interlace_pass < 4) {
+                            constexpr Array INTERLACE_ROW_STRIDES = { 8, 8, 4, 2 };
+                            constexpr Array INTERLACE_ROW_OFFSETS = { 0, 4, 2, 1 };
                             if (row + INTERLACE_ROW_STRIDES[interlace_pass] >= image.height) {
                                 ++interlace_pass;
                                 if (interlace_pass < 4)

Userland/Libraries/LibGfx/JPGLoader.cpp

@@ -861,20 +861,20 @@ static void dequantize(JPGLoadingContext& context, Vector<Macroblock>& macrobloc
 
 static void inverse_dct(const JPGLoadingContext& context, Vector<Macroblock>& macroblocks)
 {
-    static const float m0 = 2.0 * cos(1.0 / 16.0 * 2.0 * M_PI);
-    static const float m1 = 2.0 * cos(2.0 / 16.0 * 2.0 * M_PI);
-    static const float m3 = 2.0 * cos(2.0 / 16.0 * 2.0 * M_PI);
-    static const float m5 = 2.0 * cos(3.0 / 16.0 * 2.0 * M_PI);
-    static const float m2 = m0 - m5;
-    static const float m4 = m0 + m5;
-    static const float s0 = cos(0.0 / 16.0 * M_PI) / sqrt(8);
-    static const float s1 = cos(1.0 / 16.0 * M_PI) / 2.0;
-    static const float s2 = cos(2.0 / 16.0 * M_PI) / 2.0;
-    static const float s3 = cos(3.0 / 16.0 * M_PI) / 2.0;
-    static const float s4 = cos(4.0 / 16.0 * M_PI) / 2.0;
-    static const float s5 = cos(5.0 / 16.0 * M_PI) / 2.0;
-    static const float s6 = cos(6.0 / 16.0 * M_PI) / 2.0;
-    static const float s7 = cos(7.0 / 16.0 * M_PI) / 2.0;
+    const float m0 = 2.0 * cos(1.0 / 16.0 * 2.0 * M_PI);
+    const float m1 = 2.0 * cos(2.0 / 16.0 * 2.0 * M_PI);
+    const float m3 = 2.0 * cos(2.0 / 16.0 * 2.0 * M_PI);
+    const float m5 = 2.0 * cos(3.0 / 16.0 * 2.0 * M_PI);
+    const float m2 = m0 - m5;
+    const float m4 = m0 + m5;
+    const float s0 = cos(0.0 / 16.0 * M_PI) / sqrt(8);
+    const float s1 = cos(1.0 / 16.0 * M_PI) / 2.0;
+    const float s2 = cos(2.0 / 16.0 * M_PI) / 2.0;
+    const float s3 = cos(3.0 / 16.0 * M_PI) / 2.0;
+    const float s4 = cos(4.0 / 16.0 * M_PI) / 2.0;
+    const float s5 = cos(5.0 / 16.0 * M_PI) / 2.0;
+    const float s6 = cos(6.0 / 16.0 * M_PI) / 2.0;
+    const float s7 = cos(7.0 / 16.0 * M_PI) / 2.0;
 
     for (u32 vcursor = 0; vcursor < context.mblock_meta.vcount; vcursor += context.vsample_factor) {
         for (u32 hcursor = 0; hcursor < context.mblock_meta.hcount; hcursor += context.hsample_factor) {

Userland/Libraries/LibGfx/PNGLoader.cpp

@@ -25,7 +25,7 @@
 
 namespace Gfx {
 
-static const u8 png_header[8] = { 0x89, 'P', 'N', 'G', 13, 10, 26, 10 };
+static constexpr Array png_header = { 0x89, 'P', 'N', 'G', 13, 10, 26, 10 };
 
 struct PNG_IHDR {
     NetworkOrdered<u32> width;
@@ -512,7 +512,7 @@ static bool decode_png_header(PNGLoadingContext& context)
         return false;
     }
 
-    if (memcmp(context.data, png_header, sizeof(png_header)) != 0) {
+    if (memcmp(context.data, png_header.data(), sizeof(png_header)) != 0) {
         dbgln_if(PNG_DEBUG, "Invalid PNG header");
         context.state = PNGLoadingContext::State::Error;
         return false;
@@ -661,14 +661,14 @@ static int adam7_width(PNGLoadingContext& context, int pass)
     }
 }
 
-// Index 0 unused (non-interlaced case)
-static int adam7_starty[8] = { 0, 0, 0, 4, 0, 2, 0, 1 };
-static int adam7_startx[8] = { 0, 0, 4, 0, 2, 0, 1, 0 };
-static int adam7_stepy[8] = { 1, 8, 8, 8, 4, 4, 2, 2 };
-static int adam7_stepx[8] = { 1, 8, 8, 4, 4, 2, 2, 1 };
-
 static bool decode_adam7_pass(PNGLoadingContext& context, Streamer& streamer, int pass)
 {
+    // Index 0 unused (non-interlaced case)
+    constexpr Array adam7_starty = { 0, 0, 0, 4, 0, 2, 0, 1 };
+    constexpr Array adam7_startx = { 0, 0, 4, 0, 2, 0, 1, 0 };
+    constexpr Array adam7_stepy = { 1, 8, 8, 8, 4, 4, 2, 2 };
+    constexpr Array adam7_stepx = { 1, 8, 8, 4, 4, 2, 2, 1 };
+
     PNGLoadingContext subimage_context;
     subimage_context.width = adam7_width(context, pass);
     subimage_context.height = adam7_height(context, pass);

Userland/Libraries/LibGfx/Painter.cpp

@@ -1476,7 +1476,7 @@ void do_draw_text(const IntRect& rect, const TextType& text, const Font& font, T
         lines.append(line);
     }
 
-    static const int line_spacing = 4;
+    constexpr int line_spacing = 4;
     int line_height = font.glyph_height() + line_spacing;
     IntRect bounding_rect { 0, 0, 0, (static_cast<int>(lines.size()) * line_height) - line_spacing };
 

Userland/Libraries/LibJS/Runtime/NumberPrototype.cpp

@@ -5,6 +5,7 @@
  */
 
 #include <AK/Function.h>
+#include <AK/StringView.h>
 #include <LibJS/Runtime/Error.h>
 #include <LibJS/Runtime/GlobalObject.h>
 #include <LibJS/Runtime/NumberObject.h>
@@ -12,17 +13,6 @@
 
 namespace JS {
 
-static const u8 max_precision_for_radix[37] = {
-    // clang-format off
-    0,  0,  52, 32, 26, 22, 20, 18, 17, 16,
-    15, 15, 14, 14, 13, 13, 13, 12, 12, 12,
-    12, 11, 11, 11, 11, 11, 11, 10, 10, 10,
-    10, 10, 10, 10, 10, 10, 10,
-    // clang-format on
-};
-
-static char digits[] = "0123456789abcdefghijklmnopqrstuvwxyz";
-
 NumberPrototype::NumberPrototype(GlobalObject& global_object)
     : NumberObject(0, *global_object.object_prototype())
 {
@@ -41,6 +31,8 @@ NumberPrototype::~NumberPrototype()
 
 JS_DEFINE_NATIVE_FUNCTION(NumberPrototype::to_string)
 {
+    constexpr StringView digits = "0123456789abcdefghijklmnopqrstuvwxyz";
+
     Value number_value;
 
     auto this_value = vm.this_value(global_object);
@@ -107,6 +99,14 @@ JS_DEFINE_NATIVE_FUNCTION(NumberPrototype::to_string)
     if (decimal_part != 0.0) {
         characters.append('.');
 
+        constexpr u8 max_precision_for_radix[37] = {
+            // clang-format off
+            0,  0,  52, 32, 26, 22, 20, 18, 17, 16,
+            15, 15, 14, 14, 13, 13, 13, 12, 12, 12,
+            12, 11, 11, 11, 11, 11, 11, 10, 10, 10,
+            10, 10, 10, 10, 10, 10, 10,
+            // clang-format on
+        };
         u8 precision = max_precision_for_radix[radix];
 
         for (u8 i = 0; i < precision; ++i) {

Userland/Libraries/LibJS/Runtime/Value.cpp

@@ -37,7 +37,7 @@
 namespace JS {
 
 // Used in various abstract operations to make it obvious when a non-optional return value must be discarded.
-static const double INVALID { 0 };
+static constexpr double INVALID { 0 };
 
 static inline bool same_type_for_equality(const Value& lhs, const Value& rhs)
 {

Userland/Libraries/LibM/math.cpp

@@ -56,11 +56,11 @@ union FloatExtractor;
 // This assumes long double is 80 bits, which is true with GCC on Intel platforms
 template<>
 union FloatExtractor<long double> {
-    static const int mantissa_bits = 64;
-    static const unsigned long long mantissa_max = ~0u;
-    static const int exponent_bias = 16383;
-    static const int exponent_bits = 15;
-    static const unsigned exponent_max = 32767;
+    static constexpr int mantissa_bits = 64;
+    static constexpr unsigned long long mantissa_max = ~0u;
+    static constexpr int exponent_bias = 16383;
+    static constexpr int exponent_bits = 15;
+    static constexpr unsigned exponent_max = 32767;
     struct {
         unsigned long long mantissa;
         unsigned exponent : 15;
@@ -72,11 +72,11 @@ union FloatExtractor<long double> {
 
 template<>
 union FloatExtractor<double> {
-    static const int mantissa_bits = 52;
-    static const unsigned long long mantissa_max = (1ull << 52) - 1;
-    static const int exponent_bias = 1023;
-    static const int exponent_bits = 11;
-    static const unsigned exponent_max = 2047;
+    static constexpr int mantissa_bits = 52;
+    static constexpr unsigned long long mantissa_max = (1ull << 52) - 1;
+    static constexpr int exponent_bias = 1023;
+    static constexpr int exponent_bits = 11;
+    static constexpr unsigned exponent_max = 2047;
     struct {
         unsigned long long mantissa : 52;
         unsigned exponent : 11;
@@ -87,11 +87,11 @@ union FloatExtractor<double> {
 
 template<>
 union FloatExtractor<float> {
-    static const int mantissa_bits = 23;
-    static const unsigned mantissa_max = (1 << 23) - 1;
-    static const int exponent_bias = 127;
-    static const int exponent_bits = 8;
-    static const unsigned exponent_max = 255;
+    static constexpr int mantissa_bits = 23;
+    static constexpr unsigned mantissa_max = (1 << 23) - 1;
+    static constexpr int exponent_bias = 127;
+    static constexpr int exponent_bits = 8;
+    static constexpr unsigned exponent_max = 255;
     struct {
         unsigned long long mantissa : 23;
         unsigned exponent : 8;

Userland/Libraries/LibPthread/forward.cpp

@@ -6,25 +6,24 @@
 
 #include <LibC/bits/pthread_forward.h>
 
-static const PthreadFunctions s_functions = {
-    .pthread_mutex_trylock = pthread_mutex_trylock,
-    .pthread_mutex_destroy = pthread_mutex_destroy,
-
-    .pthread_mutexattr_init = pthread_mutexattr_init,
-    .pthread_mutexattr_settype = pthread_mutexattr_settype,
-    .pthread_mutexattr_destroy = pthread_mutexattr_destroy,
+[[gnu::constructor]] static void forward_pthread_functions()
+{
+    constexpr PthreadFunctions s_functions = {
+        .pthread_mutex_trylock = pthread_mutex_trylock,
+        .pthread_mutex_destroy = pthread_mutex_destroy,
 
-    .pthread_once = pthread_once,
+        .pthread_mutexattr_init = pthread_mutexattr_init,
+        .pthread_mutexattr_settype = pthread_mutexattr_settype,
+        .pthread_mutexattr_destroy = pthread_mutexattr_destroy,
 
-    .pthread_cond_broadcast = pthread_cond_broadcast,
-    .pthread_cond_init = pthread_cond_init,
-    .pthread_cond_signal = pthread_cond_signal,
-    .pthread_cond_wait = pthread_cond_wait,
-    .pthread_cond_destroy = pthread_cond_destroy,
-    .pthread_cond_timedwait = pthread_cond_timedwait,
-};
+        .pthread_once = pthread_once,
 
-[[gnu::constructor]] static void forward_pthread_functions()
-{
+        .pthread_cond_broadcast = pthread_cond_broadcast,
+        .pthread_cond_init = pthread_cond_init,
+        .pthread_cond_signal = pthread_cond_signal,
+        .pthread_cond_wait = pthread_cond_wait,
+        .pthread_cond_destroy = pthread_cond_destroy,
+        .pthread_cond_timedwait = pthread_cond_timedwait,
+    };
     __init_pthread_forward(s_functions);
 }

Userland/Libraries/LibRegex/RegexMatcher.h

@@ -23,8 +23,8 @@
 
 namespace regex {
 
-static const constexpr size_t c_max_recursion = 5000;
-static const constexpr size_t c_match_preallocation_count = 0;
+static constexpr size_t c_max_recursion = 5000;
+static constexpr size_t c_match_preallocation_count = 0;
 
 struct RegexResult final {
     bool success { false };

Userland/Libraries/LibVT/Attribute.h

@@ -16,8 +16,8 @@ namespace VT {
 struct Attribute {
     Attribute() { reset(); }
 
-    static const u32 default_foreground_color = xterm_colors[7];
-    static const u32 default_background_color = xterm_colors[0];
+    static constexpr u32 default_foreground_color = xterm_colors[7];
+    static constexpr u32 default_background_color = xterm_colors[0];
 
     void reset()
     {

Userland/Libraries/LibWeb/Cookie/ParsedCookie.cpp

@@ -5,6 +5,7 @@
  */
 
 #include "ParsedCookie.h"
+#include <AK/Array.h>
 #include <AK/StdLibExtras.h>
 #include <AK/Vector.h>
 #include <LibIPC/Decoder.h>
@@ -264,7 +265,7 @@ Optional<Core::DateTime> parse_date_time(StringView date_string)
     };
 
     auto parse_month = [&](StringView token) {
-        static const char* months[] { "jan", "feb", "mar", "apr", "may", "jun", "jul", "aug", "sep", "oct", "nov", "dec" };
+        constexpr Array months { "jan", "feb", "mar", "apr", "may", "jun", "jul", "aug", "sep", "oct", "nov", "dec" };
 
         for (unsigned i = 0; i < 12; ++i) {
             if (token.equals_ignoring_case(months[i])) {

Userland/Libraries/LibX86/Instruction.cpp

@@ -100,7 +100,7 @@ static void build(InstructionDescriptor* table, u8 op, const char* mnemonic, Ins
     case OP_AX_moff16:
     case OP_EAX_moff32:
     case OP_NEAR_imm:
-        d.imm1_bytes = CurrentAddressSize;
+        d.imm1_bytes = InstructionDescriptor::CurrentAddressSize;
         break;
     //default:
     case InvalidFormat:

Userland/Libraries/LibX86/Instruction.h

@@ -28,9 +28,9 @@ protected:
 
 template<typename T>
 struct TypeTrivia {
-    static const size_t bits = sizeof(T) * 8;
-    static const T sign_bit = 1 << (bits - 1);
-    static const T mask = MakeUnsigned<T>(-1);
+    static constexpr size_t bits = sizeof(T) * 8;
+    static constexpr T sign_bit = 1 << (bits - 1);
+    static constexpr T mask = MakeUnsigned<T>(-1);
 };
 
 template<typename T, typename U>
@@ -159,9 +159,9 @@ enum InstructionFormat {
     OP_NEAR_imm,
 };
 
-static const unsigned CurrentAddressSize = 0xB33FBABE;
-
 struct InstructionDescriptor {
+    static constexpr unsigned CurrentAddressSize = 0xB33FBABE;
+
     InstructionHandler handler { nullptr };
     bool opcode_has_register_index { false };
     const char* mnemonic { nullptr };

Userland/Services/Taskbar/ShutdownDialog.cpp

@@ -5,7 +5,7 @@
  */
 
 #include "ShutdownDialog.h"
-#include <AK/String.h>
+#include <AK/StringView.h>
 #include <AK/Vector.h>
 #include <LibGUI/BoxLayout.h>
 #include <LibGUI/Button.h>
@@ -17,7 +17,7 @@
 #include <LibGfx/FontDatabase.h>
 
 struct Option {
-    String title;
+    StringView title;
     Vector<char const*> cmd;
     bool enabled;
     bool default_action;

Userland/Services/WindowServer/Compositor.cpp

@@ -634,7 +634,7 @@ void Compositor::flip_buffers()
 
 void Compositor::run_animations(Gfx::DisjointRectSet& flush_rects)
 {
-    static const int minimize_animation_steps = 10;
+    constexpr int minimize_animation_steps = 10;
     auto& painter = *m_back_painter;
     Gfx::PainterStateSaver saver(painter);
     painter.set_draw_op(Gfx::Painter::DrawOp::Invert);

Userland/Services/WindowServer/Menu.cpp

@@ -55,7 +55,7 @@ const Gfx::Font& Menu::font() const
     return Gfx::FontDatabase::default_font();
 }
 
-static const char* s_checked_bitmap_data = {
+static constexpr char s_checked_bitmap_data[] = {
     "         "
     "       # "
     "      ## "
@@ -67,7 +67,7 @@ static const char* s_checked_bitmap_data = {
     "         "
 };
 
-static const char* s_submenu_arrow_bitmap_data = {
+static constexpr char s_submenu_arrow_bitmap_data[] = {
     "         "
     "   #     "
     "   ##    "
@@ -80,12 +80,12 @@ static const char* s_submenu_arrow_bitmap_data = {
 };
 
 static Gfx::CharacterBitmap* s_checked_bitmap;
-static const int s_checked_bitmap_width = 9;
-static const int s_checked_bitmap_height = 9;
-static const int s_submenu_arrow_bitmap_width = 9;
-static const int s_submenu_arrow_bitmap_height = 9;
-static const int s_item_icon_width = 16;
-static const int s_stripe_width = 24;
+static constexpr int s_checked_bitmap_width = 9;
+static constexpr int s_checked_bitmap_height = 9;
+static constexpr int s_submenu_arrow_bitmap_width = 9;
+static constexpr int s_submenu_arrow_bitmap_height = 9;
+static constexpr int s_item_icon_width = 16;
+static constexpr int s_stripe_width = 24;
 
 int Menu::content_width() const
 {

Userland/Services/WindowServer/WindowManager.cpp

@@ -59,7 +59,7 @@ WindowManager::~WindowManager()
 
 NonnullRefPtr<Cursor> WindowManager::get_cursor(const String& name)
 {
-    static const auto s_default_cursor_path = "/res/cursors/arrow.x2y2.png";
+    constexpr auto s_default_cursor_path = "/res/cursors/arrow.x2y2.png";
     auto path = m_config->read_entry("Cursor", name, s_default_cursor_path);
     auto gb = Gfx::Bitmap::load_from_file(path, compositor_icon_scale());
     if (gb)

Userland/Utilities/ddate.cpp

@@ -42,9 +42,9 @@ public:
     }
 
 private:
-    static const int m_days_in_week = 5;
-    static const int m_days_in_season = 73;
-    static const int m_st_tibs_day_of_yold = 60;
+    static constexpr int m_days_in_week = 5;
+    static constexpr int m_days_in_season = 73;
+    static constexpr int m_st_tibs_day_of_yold = 60;
     Core::DateTime m_gregorian_date;
     String m_day_of_week;
     String m_season;

Userland/Utilities/lspci.cpp

@@ -8,6 +8,7 @@
 #include <AK/JsonArray.h>
 #include <AK/JsonObject.h>
 #include <AK/String.h>
+#include <AK/StringView.h>
 #include <LibCore/ArgsParser.h>
 #include <LibCore/File.h>
 #include <LibPCIDB/Database.h>
@@ -16,8 +17,8 @@
 
 static bool flag_show_numerical = false;
 
-static const char* format_numerical = "{:04x}:{:02x}:{:02x}.{} {}: {}:{} (rev {:02x})";
-static const char* format_textual = "{:04x}:{:02x}:{:02x}.{} {}: {} {} (rev {:02x})";
+static constexpr StringView format_numerical = "{:04x}:{:02x}:{:02x}.{} {}: {}:{} (rev {:02x})";
+static constexpr StringView format_textual = "{:04x}:{:02x}:{:02x}.{} {}: {} {} (rev {:02x})";
 
 int main(int argc, char** argv)
 {
@@ -43,7 +44,7 @@ int main(int argc, char** argv)
     args_parser.add_option(flag_show_numerical, "Show numerical IDs", "numerical", 'n');
     args_parser.parse(argc, argv);
 
-    const char* format = flag_show_numerical ? format_numerical : format_textual;
+    const auto format = flag_show_numerical ? format_numerical : format_textual;
 
     RefPtr<PCIDB::Database> db;
     if (!flag_show_numerical) {