Fixed build using Visual Studio 2017

As _BitScanForward and friends are not marked constexpr in Visual Studio,
functions using these may not be marked either.

Task-number: QTBUG-57086
Change-Id: I29cfa4459580b5740f1011e7f39309844518ce03
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Erik Verbruggen <erik.verbruggen@qt.io>

1 files changed, 21 insertions, 15 deletions

diff --git a/src/corelib/tools/qalgorithms.h b/src/corelib/tools/qalgorithms.h
index 303374b06d..7e846956f5 100644
--- a/src/corelib/tools/qalgorithms.h
+++ b/src/corelib/tools/qalgorithms.h
@@ -589,15 +589,16 @@ Q_DECL_CONSTEXPR Q_ALWAYS_INLINE uint qt_builtin_popcountll(quint64 v) Q_DECL_NO
     return __builtin_popcountll(v);
 }
 #elif defined(Q_CC_MSVC) && !defined(Q_OS_WINCE) && !defined(Q_PROCESSOR_ARM)
+#define QT_POPCOUNT_CONSTEXPR
 #define QT_HAS_BUILTIN_CTZ
-Q_DECL_CONSTEXPR Q_ALWAYS_INLINE unsigned long qt_builtin_ctz(quint32 val)
+Q_ALWAYS_INLINE unsigned long qt_builtin_ctz(quint32 val)
 {
     unsigned long result;
     _BitScanForward(&result, val);
     return result;
 }
 #define QT_HAS_BUILTIN_CLZ
-Q_DECL_CONSTEXPR Q_ALWAYS_INLINE unsigned long qt_builtin_clz(quint32 val)
+Q_ALWAYS_INLINE unsigned long qt_builtin_clz(quint32 val)
 {
     unsigned long result;
     _BitScanReverse(&result, val);
@@ -610,7 +611,7 @@ Q_DECL_CONSTEXPR Q_ALWAYS_INLINE unsigned long qt_builtin_clz(quint32 val)
 #if Q_PROCESSOR_WORDSIZE == 8
 // These are only defined for 64bit builds.
 #define QT_HAS_BUILTIN_CTZLL
-Q_DECL_CONSTEXPR Q_ALWAYS_INLINE unsigned long qt_builtin_ctzll(quint64 val)
+Q_ALWAYS_INLINE unsigned long qt_builtin_ctzll(quint64 val)
 {
     unsigned long result;
     _BitScanForward64(&result, val);
@@ -618,7 +619,7 @@ Q_DECL_CONSTEXPR Q_ALWAYS_INLINE unsigned long qt_builtin_ctzll(quint64 val)
 }
 // MSVC calls it _BitScanReverse and returns the carry flag, which we don't need
 #define QT_HAS_BUILTIN_CLZLL
-Q_DECL_CONSTEXPR Q_ALWAYS_INLINE unsigned long qt_builtin_clzll(quint64 val)
+Q_ALWAYS_INLINE unsigned long qt_builtin_clzll(quint64 val)
 {
     unsigned long result;
     _BitScanReverse64(&result, val);
@@ -628,31 +629,31 @@ Q_DECL_CONSTEXPR Q_ALWAYS_INLINE unsigned long qt_builtin_clzll(quint64 val)
 }
 #endif // MSVC 64bit
 #  define QT_HAS_BUILTIN_CTZS
-Q_DECL_CONSTEXPR Q_ALWAYS_INLINE uint qt_builtin_ctzs(quint16 v) Q_DECL_NOTHROW
+Q_ALWAYS_INLINE uint qt_builtin_ctzs(quint16 v) Q_DECL_NOTHROW
 {
     return qt_builtin_ctz(v);
 }
 #define QT_HAS_BUILTIN_CLZS
-Q_DECL_CONSTEXPR Q_ALWAYS_INLINE uint qt_builtin_clzs(quint16 v) Q_DECL_NOTHROW
+Q_ALWAYS_INLINE uint qt_builtin_clzs(quint16 v) Q_DECL_NOTHROW
 {
     return qt_builtin_clz(v) - 16U;
 }
 #define QALGORITHMS_USE_BUILTIN_POPCOUNT
-Q_DECL_CONSTEXPR Q_ALWAYS_INLINE uint qt_builtin_popcount(quint32 v) Q_DECL_NOTHROW
+Q_ALWAYS_INLINE uint qt_builtin_popcount(quint32 v) Q_DECL_NOTHROW
 {
     return __popcnt(v);
 }
-Q_DECL_CONSTEXPR Q_ALWAYS_INLINE uint qt_builtin_popcount(quint8 v) Q_DECL_NOTHROW
+Q_ALWAYS_INLINE uint qt_builtin_popcount(quint8 v) Q_DECL_NOTHROW
 {
     return __popcnt16(v);
 }
-Q_DECL_CONSTEXPR Q_ALWAYS_INLINE uint qt_builtin_popcount(quint16 v) Q_DECL_NOTHROW
+Q_ALWAYS_INLINE uint qt_builtin_popcount(quint16 v) Q_DECL_NOTHROW
 {
     return __popcnt16(v);
 }
 #if Q_PROCESSOR_WORDSIZE == 8
 #define QALGORITHMS_USE_BUILTIN_POPCOUNTLL
-Q_DECL_CONSTEXPR Q_ALWAYS_INLINE uint qt_builtin_popcountll(quint64 v) Q_DECL_NOTHROW
+Q_ALWAYS_INLINE uint qt_builtin_popcountll(quint64 v) Q_DECL_NOTHROW
 {
     return __popcnt64(v);
 }
@@ -660,9 +661,13 @@ Q_DECL_CONSTEXPR Q_ALWAYS_INLINE uint qt_builtin_popcountll(quint64 v) Q_DECL_NO
 #endif // MSVC
 #endif // QT_HAS_CONSTEXPR_BUILTINS
 
+#ifndef QT_POPCOUNT_CONSTEXPR
+#define QT_POPCOUNT_CONSTEXPR Q_DECL_CONSTEXPR
+#endif
+
 } //namespace QAlgorithmsPrivate
 
-Q_DECL_CONST_FUNCTION Q_DECL_CONSTEXPR inline uint qPopulationCount(quint32 v) Q_DECL_NOTHROW
+Q_DECL_CONST_FUNCTION QT_POPCOUNT_CONSTEXPR inline uint qPopulationCount(quint32 v) Q_DECL_NOTHROW
 {
 #ifdef QALGORITHMS_USE_BUILTIN_POPCOUNT
     return QAlgorithmsPrivate::qt_builtin_popcount(v);
@@ -675,7 +680,7 @@ Q_DECL_CONST_FUNCTION Q_DECL_CONSTEXPR inline uint qPopulationCount(quint32 v) Q
 #endif
 }
 
-Q_DECL_CONST_FUNCTION Q_DECL_CONSTEXPR inline uint qPopulationCount(quint8 v) Q_DECL_NOTHROW
+Q_DECL_CONST_FUNCTION QT_POPCOUNT_CONSTEXPR inline uint qPopulationCount(quint8 v) Q_DECL_NOTHROW
 {
 #ifdef QALGORITHMS_USE_BUILTIN_POPCOUNT
     return QAlgorithmsPrivate::qt_builtin_popcount(v);
@@ -685,7 +690,7 @@ Q_DECL_CONST_FUNCTION Q_DECL_CONSTEXPR inline uint qPopulationCount(quint8 v) Q_
 #endif
 }
 
-Q_DECL_CONST_FUNCTION Q_DECL_CONSTEXPR inline uint qPopulationCount(quint16 v) Q_DECL_NOTHROW
+Q_DECL_CONST_FUNCTION QT_POPCOUNT_CONSTEXPR inline uint qPopulationCount(quint16 v) Q_DECL_NOTHROW
 {
 #ifdef QALGORITHMS_USE_BUILTIN_POPCOUNT
     return QAlgorithmsPrivate::qt_builtin_popcount(v);
@@ -696,7 +701,7 @@ Q_DECL_CONST_FUNCTION Q_DECL_CONSTEXPR inline uint qPopulationCount(quint16 v) Q
 #endif
 }
 
-Q_DECL_CONST_FUNCTION Q_DECL_CONSTEXPR inline uint qPopulationCount(quint64 v) Q_DECL_NOTHROW
+Q_DECL_CONST_FUNCTION QT_POPCOUNT_CONSTEXPR inline uint qPopulationCount(quint64 v) Q_DECL_NOTHROW
 {
 #ifdef QALGORITHMS_USE_BUILTIN_POPCOUNTLL
     return QAlgorithmsPrivate::qt_builtin_popcountll(v);
@@ -711,7 +716,7 @@ Q_DECL_CONST_FUNCTION Q_DECL_CONSTEXPR inline uint qPopulationCount(quint64 v) Q
 #endif
 }
 
-Q_DECL_CONST_FUNCTION Q_DECL_CONSTEXPR inline uint qPopulationCount(long unsigned int v) Q_DECL_NOTHROW
+Q_DECL_CONST_FUNCTION QT_POPCOUNT_CONSTEXPR inline uint qPopulationCount(long unsigned int v) Q_DECL_NOTHROW
 {
     return qPopulationCount(static_cast<quint64>(v));
 }
@@ -719,6 +724,7 @@ Q_DECL_CONST_FUNCTION Q_DECL_CONSTEXPR inline uint qPopulationCount(long unsigne
 #if defined(Q_CC_GNU) && !defined(Q_CC_CLANG)
 #undef QALGORITHMS_USE_BUILTIN_POPCOUNT
 #endif
+#undef QT_POPCOUNT_CONSTEXPR
 
 Q_DECL_RELAXED_CONSTEXPR inline uint qCountTrailingZeroBits(quint32 v) Q_DECL_NOTHROW
 {