Get rid of Q_COMPILER_CONSTEXPR checks

Is required now.

Change-Id: I62e95929d1649ea1390392230b619bd56d2a0349
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

8 files changed, 4 insertions, 35 deletions

diff --git a/src/corelib/global/qnamespace.h b/src/corelib/global/qnamespace.h
index 157928c958..0a4f025d6a 100644
--- a/src/corelib/global/qnamespace.h
+++ b/src/corelib/global/qnamespace.h
@@ -1601,16 +1601,10 @@ namespace Qt {
         TitleBarArea    // For move
     };
 
-#if defined(Q_COMPILER_CONSTEXPR)
     enum class Initialization {
         Uninitialized
     };
-    [[maybe_unused]] static constexpr Initialization Uninitialized = Initialization::Uninitialized;
-#else
-    enum Initialization {
-        Uninitialized
-    };
-#endif
+    [[maybe_unused]] static inline constexpr Initialization Uninitialized = Initialization::Uninitialized;
 
     enum CoordinateSystem {
         DeviceCoordinates,
diff --git a/src/corelib/global/qrandom.cpp b/src/corelib/global/qrandom.cpp
index b71097926c..ca16566c1c 100644
--- a/src/corelib/global/qrandom.cpp
+++ b/src/corelib/global/qrandom.cpp
@@ -361,15 +361,13 @@ struct QRandomGenerator::SystemAndGlobalGenerators
     SystemGenerator sys;
     alignas(64) std::aligned_storage<sizeof(QRandomGenerator64), 64>::type global_;
 
-#ifdef Q_COMPILER_CONSTEXPR
     constexpr SystemAndGlobalGenerators()
         : globalPRNGMutex{}, system_{0}, sys{}, global_{}
     {}
-#endif
 
     void confirmLiteral()
     {
-#if defined(Q_COMPILER_CONSTEXPR) && !defined(Q_CC_MSVC) && !defined(Q_OS_INTEGRITY)
+#if !defined(Q_CC_MSVC) && !defined(Q_OS_INTEGRITY)
         // Currently fails to compile with MSVC 2017, saying QBasicMutex is not
         // a literal type. Disassembly with MSVC 2013 and 2015 shows it is
         // actually a literal; MSVC 2017 has a bug relating to this, so we're
diff --git a/src/corelib/text/qlocale_p.h b/src/corelib/text/qlocale_p.h
index aad344eccc..69b6136313 100644
--- a/src/corelib/text/qlocale_p.h
+++ b/src/corelib/text/qlocale_p.h
@@ -504,7 +504,6 @@ constexpr inline bool ascii_isspace(uchar c)
     return c >= 1u && c <= 32u && (AsciiSpaceMask >> uint(c - 1)) & 1u;
 }
 
-#if defined(Q_COMPILER_CONSTEXPR)
 static_assert(ascii_isspace(' '));
 static_assert(ascii_isspace('\t'));
 static_assert(ascii_isspace('\n'));
@@ -518,7 +517,6 @@ static_assert(!ascii_isspace('\177'));
 static_assert(!ascii_isspace(uchar('\200')));
 static_assert(!ascii_isspace(uchar('\xA0')));
 static_assert(!ascii_isspace(uchar('\377')));
-#endif
 
 QT_END_NAMESPACE
 
diff --git a/src/corelib/thread/qatomic_cxx11.h b/src/corelib/thread/qatomic_cxx11.h
index db78da5437..bf487bbf1f 100644
--- a/src/corelib/thread/qatomic_cxx11.h
+++ b/src/corelib/thread/qatomic_cxx11.h
@@ -478,11 +478,7 @@ template <typename X> struct QAtomicOps
     }
 };
 
-#if defined(Q_COMPILER_CONSTEXPR)
 #  define Q_BASIC_ATOMIC_INITIALIZER(a)     { a }
-#else
-#  define Q_BASIC_ATOMIC_INITIALIZER(a)     { ATOMIC_VAR_INIT(a) }
-#endif
 
 QT_END_NAMESPACE
 
diff --git a/src/corelib/thread/qbasicatomic.h b/src/corelib/thread/qbasicatomic.h
index 8c6440a7d7..cb62ed2722 100644
--- a/src/corelib/thread/qbasicatomic.h
+++ b/src/corelib/thread/qbasicatomic.h
@@ -49,7 +49,7 @@
 // If C++11 atomics are supported, use them!
 // Note that constexpr support is sometimes disabled in QNX or INTEGRITY builds,
 // but their libraries have <atomic>.
-#elif defined(Q_COMPILER_ATOMICS) && (defined(Q_COMPILER_CONSTEXPR) || defined(Q_OS_QNX) || defined(Q_OS_INTEGRITY))
+#elif defined(Q_COMPILER_ATOMICS)
 #  include <QtCore/qatomic_cxx11.h>
 
 // We only support one fallback: MSVC, because even on version 2015, it lacks full constexpr support
@@ -75,16 +75,7 @@ QT_END_NAMESPACE
 
 // New atomics
 
-#if defined(Q_COMPILER_CONSTEXPR)
-# if defined(Q_CC_CLANG) && Q_CC_CLANG < 303
-   /*
-      Do not define QT_BASIC_ATOMIC_HAS_CONSTRUCTORS for Clang before version 3.3.
-      For details about the bug: see http://llvm.org/bugs/show_bug.cgi?id=12670
-    */
-# else
-#  define QT_BASIC_ATOMIC_HAS_CONSTRUCTORS
-# endif
-#endif
+#define QT_BASIC_ATOMIC_HAS_CONSTRUCTORS
 
 template <typename T>
 class QBasicAtomicInteger
diff --git a/src/corelib/tools/qfreelist_p.h b/src/corelib/tools/qfreelist_p.h
index a90cb14cf5..f54e5aad65 100644
--- a/src/corelib/tools/qfreelist_p.h
+++ b/src/corelib/tools/qfreelist_p.h
@@ -207,9 +207,7 @@ public:
 template <typename T, typename ConstantsType>
 constexpr inline QFreeList<T, ConstantsType>::QFreeList()
     :
-#if defined(Q_COMPILER_CONSTEXPR)
       _v{}, // uniform initialization required
-#endif
       _next(ConstantsType::InitialNextValue)
 { }
 
diff --git a/src/gui/painting/qpixellayout.cpp b/src/gui/painting/qpixellayout.cpp
index c931cc0a09..0b1e736ec8 100644
--- a/src/gui/painting/qpixellayout.cpp
+++ b/src/gui/painting/qpixellayout.cpp
@@ -511,9 +511,7 @@ static void QT_FASTCALL rbSwap(uchar *dst, const uchar *src, int count)
     constexpr uchar gShift = greenShift<Format>();
     constexpr uchar bWidth = blueWidth<Format>();
     constexpr uchar bShift = blueShift<Format>();
-#ifdef Q_COMPILER_CONSTEXPR
     static_assert(rWidth == bWidth);
-#endif
     constexpr uint redBlueMask = (1 << rWidth) - 1;
     constexpr uint alphaGreenMask = (((1 << aWidth) - 1) << aShift)
                                     | (((1 << gWidth) - 1) << gShift);
diff --git a/src/widgets/widgets/qcalendarwidget.cpp b/src/widgets/widgets/qcalendarwidget.cpp
index e9774aa556..e3adf0a852 100644
--- a/src/widgets/widgets/qcalendarwidget.cpp
+++ b/src/widgets/widgets/qcalendarwidget.cpp
@@ -829,11 +829,7 @@ class StaticDayOfWeekAssociativeArray {
     static constexpr int day2idx(Qt::DayOfWeek day) noexcept { return int(day) - 1; } // alt: day % 7
 public:
     constexpr StaticDayOfWeekAssociativeArray() noexcept(noexcept(T()))
-#ifdef Q_COMPILER_CONSTEXPR
         : contained{}, data{}   // arrays require uniform initialization
-#else
-        : contained(), data()
-#endif
     {}
 
     constexpr bool contains(Qt::DayOfWeek day) const noexcept { return contained[day2idx(day)]; }