Fix -Wconversion warnings where possible.

In order to detect "int foo = myQReal" mistakes, one needs to compile with -Wconversion.
However that flag triggers many warnings inside Qt. This commit fixes many of them, like
qchar.h:295: warning: conversion to 'ushort' from 'unsigned int' may alter its value
qglobal.h:1026: warning: conversion to 'qreal' from 'qint64' may alter its value
qbytearray.h:441: warning: conversion to 'char' from 'int' may alter its value
Other warnings remain (such as those coming from bitfields)

Merge-request: 1460
Reviewed-by: Thiago Macieira <thiago.macieira@nokia.com>

6 files changed, 25 insertions, 25 deletions

diff --git a/src/corelib/tools/qalgorithms.h b/src/corelib/tools/qalgorithms.h
index 312cd4c..a68ce27 100644
--- a/src/corelib/tools/qalgorithms.h
+++ b/src/corelib/tools/qalgorithms.h
@@ -227,7 +227,7 @@ template <typename RandomAccessIterator, typename T>
 Q_OUTOFLINE_TEMPLATE RandomAccessIterator qLowerBound(RandomAccessIterator begin, RandomAccessIterator end, const T &value)
 {
     // Implementation is duplicated from QAlgorithmsPrivate to keep existing code
-    // compiling. We have to allow using *begin and value with different types, 
+    // compiling. We have to allow using *begin and value with different types,
     // and then implementing operator< for those types.
     RandomAccessIterator middle;
     int n = end - begin;
@@ -351,7 +351,7 @@ template <typename RandomAccessIterator, typename T, typename LessThan>
 Q_OUTOFLINE_TEMPLATE void qSortHelper(RandomAccessIterator start, RandomAccessIterator end, const T &t, LessThan lessThan)
 {
 top:
-    int span = end - start;
+    int span = int(end - start);
     if (span < 2)
         return;
 
@@ -417,9 +417,9 @@ Q_OUTOFLINE_TEMPLATE void qReverse(RandomAccessIterator begin, RandomAccessItera
 template <typename RandomAccessIterator>
 Q_OUTOFLINE_TEMPLATE void qRotate(RandomAccessIterator begin, RandomAccessIterator middle, RandomAccessIterator end)
 {
-    qReverse(begin, middle); 
-    qReverse(middle, end); 
-    qReverse(begin, end); 
+    qReverse(begin, middle);
+    qReverse(middle, end);
+    qReverse(begin, end);
 }
 
 template <typename RandomAccessIterator, typename T, typename LessThan>
@@ -463,7 +463,7 @@ Q_OUTOFLINE_TEMPLATE void qStableSortHelper(RandomAccessIterator begin, RandomAc
     const int span = end - begin;
     if (span < 2)
        return;
-       
+
     const RandomAccessIterator middle = begin + span / 2;
     qStableSortHelper(begin, middle, t, lessThan);
     qStableSortHelper(middle, end, t, lessThan);
@@ -480,7 +480,7 @@ template <typename RandomAccessIterator, typename T, typename LessThan>
 Q_OUTOFLINE_TEMPLATE RandomAccessIterator qLowerBoundHelper(RandomAccessIterator begin, RandomAccessIterator end, const T &value, LessThan lessThan)
 {
     RandomAccessIterator middle;
-    int n = end - begin;
+    int n = int(end - begin);
     int half;
 
     while (n > 0) {
diff --git a/src/corelib/tools/qbitarray.h b/src/corelib/tools/qbitarray.h
index c922262..2ae77b7 100644
--- a/src/corelib/tools/qbitarray.h
+++ b/src/corelib/tools/qbitarray.h
@@ -121,19 +121,19 @@ inline bool QBitArray::testBit(int i) const
 
 inline void QBitArray::setBit(int i)
 { Q_ASSERT(i >= 0 && i < size());
- *(reinterpret_cast<uchar*>(d.data())+1+(i>>3)) |= (1 << (i & 7)); }
+ *(reinterpret_cast<uchar*>(d.data())+1+(i>>3)) |= uchar(1 << (i & 7)); }
 
 inline void QBitArray::clearBit(int i)
 { Q_ASSERT(i >= 0 && i < size());
- *(reinterpret_cast<uchar*>(d.data())+1+(i>>3)) &= ~(1 << (i & 7)); }
+ *(reinterpret_cast<uchar*>(d.data())+1+(i>>3)) &= ~uchar(1 << (i & 7)); }
 
 inline void QBitArray::setBit(int i, bool val)
 { if (val) setBit(i); else clearBit(i); }
 
 inline bool QBitArray::toggleBit(int i)
 { Q_ASSERT(i >= 0 &&  i < size());
- uchar b = 1<< (i&7); uchar* p = reinterpret_cast<uchar*>(d.data())+1+(i>>3);
- uchar c = *p&b; *p^=b; return c!=0; }
+ uchar b = uchar(1<<(i&7)); uchar* p = reinterpret_cast<uchar*>(d.data())+1+(i>>3);
+ uchar c = uchar(*p&b); *p^=b; return c!=0; }
 
 inline bool QBitArray::operator[](int i) const { return testBit(i); }
 inline bool QBitArray::operator[](uint i) const { return testBit(i); }
diff --git a/src/corelib/tools/qbytearray.h b/src/corelib/tools/qbytearray.h
index 14425ba..e258481 100644
--- a/src/corelib/tools/qbytearray.h
+++ b/src/corelib/tools/qbytearray.h
@@ -442,10 +442,10 @@ class Q_CORE_EXPORT QByteRef {
 public:
 #ifdef Q_COMPILER_MANGLES_RETURN_TYPE
     inline operator const char() const
-        { return i < a.d->size ? a.d->data[i] : 0; }
+        { return i < a.d->size ? a.d->data[i] : char(0); }
 #else
     inline operator char() const
-        { return i < a.d->size ? a.d->data[i] : 0; }
+        { return i < a.d->size ? a.d->data[i] : char(0); }
 #endif
     inline QByteRef &operator=(char c)
         { if (i >= a.d->size) a.expand(i); else a.detach();
diff --git a/src/corelib/tools/qchar.h b/src/corelib/tools/qchar.h
index bcfb361..5ece472 100644
--- a/src/corelib/tools/qchar.h
+++ b/src/corelib/tools/qchar.h
@@ -292,10 +292,10 @@ public:
         return (uint(high.ucs)<<10) + low.ucs - 0x35fdc00;
     }
     static inline ushort highSurrogate(uint ucs4) {
-        return (ucs4>>10) + 0xd7c0;
+        return ushort((ucs4>>10) + 0xd7c0);
     }
     static inline ushort lowSurrogate(uint ucs4) {
-        return ucs4%0x400 + 0xdc00;
+        return ushort(ucs4%0x400 + 0xdc00);
     }
 
     static Category QT_FASTCALL category(uint ucs4);
@@ -366,7 +366,7 @@ inline char QChar::toLatin1() const { return ucs > 0xff ? '\0' : char(ucs); }
 #endif
 inline QChar QChar::fromLatin1(char c) { return QChar(ushort(uchar(c))); }
 
-inline QChar::QChar(uchar c, uchar r) : ucs((r << 8) | c){}
+inline QChar::QChar(uchar c, uchar r) : ucs(ushort((r << 8) | c)){}
 inline QChar::QChar(short rc) : ucs(ushort(rc)){}
 inline QChar::QChar(uint rc) : ucs(ushort(rc & 0xffff)){}
 inline QChar::QChar(int rc) : ucs(ushort(rc & 0xffff)){}
@@ -374,9 +374,9 @@ inline QChar::QChar(SpecialCharacter s) : ucs(ushort(s)) {}
 inline QChar::QChar(QLatin1Char ch) : ucs(ch.unicode()) {}
 
 inline void QChar::setCell(uchar acell)
-{ ucs = (ucs & 0xff00) + acell; }
+{ ucs = ushort((ucs & 0xff00) + acell); }
 inline void QChar::setRow(uchar arow)
-{ ucs = (ushort(arow)<<8) + (ucs&0xff); }
+{ ucs = ushort((ushort(arow)<<8) + (ucs&0xff)); }
 
 inline bool operator==(QChar c1, QChar c2) { return c1.unicode() == c2.unicode(); }
 inline bool operator!=(QChar c1, QChar c2) { return c1.unicode() != c2.unicode(); }
diff --git a/src/corelib/tools/qlist.h b/src/corelib/tools/qlist.h
index 3111426..49b5c0d 100644
--- a/src/corelib/tools/qlist.h
+++ b/src/corelib/tools/qlist.h
@@ -202,7 +202,7 @@ public:
         inline iterator &operator-=(int j) { i-=j; return *this; }
         inline iterator operator+(int j) const { return iterator(i+j); }
         inline iterator operator-(int j) const { return iterator(i-j); }
-        inline int operator-(iterator j) const { return i - j.i; }
+        inline int operator-(iterator j) const { return int(i - j.i); }
     };
     friend class iterator;
 
@@ -420,7 +420,7 @@ Q_INLINE_TEMPLATE QList<T> &QList<T>::operator=(const QList<T> &l)
 template <typename T>
 inline typename QList<T>::iterator QList<T>::insert(iterator before, const T &t)
 {
-    int iBefore = before.i - reinterpret_cast<Node *>(p.begin());
+    int iBefore = int(before.i - reinterpret_cast<Node *>(p.begin()));
     Node *n = reinterpret_cast<Node *>(p.insert(iBefore));
     QT_TRY {
         node_construct(n, t);
@@ -706,7 +706,7 @@ Q_OUTOFLINE_TEMPLATE QList<T> &QList<T>::operator+=(const QList<T> &l)
         node_copy(n, reinterpret_cast<Node *>(p.end()), reinterpret_cast<Node *>(l.p.begin()));
     } QT_CATCH(...) {
         // restore the old end
-        d->end -= (reinterpret_cast<Node *>(p.end()) - n);
+        d->end -= int(reinterpret_cast<Node *>(p.end()) - n);
         QT_RETHROW;
     }
     return *this;
@@ -728,7 +728,7 @@ Q_OUTOFLINE_TEMPLATE int QList<T>::indexOf(const T &t, int from) const
         Node *e = reinterpret_cast<Node *>(p.end());
         while (++n != e)
             if (n->t() == t)
-                return n - reinterpret_cast<Node *>(p.begin());
+                return int(n - reinterpret_cast<Node *>(p.begin()));
     }
     return -1;
 }
diff --git a/src/corelib/tools/qvector.h b/src/corelib/tools/qvector.h
index 60d6921..2737a87 100644
--- a/src/corelib/tools/qvector.h
+++ b/src/corelib/tools/qvector.h
@@ -543,7 +543,7 @@ void QVector<T>::append(const T &t)
 template <typename T>
 Q_TYPENAME QVector<T>::iterator QVector<T>::insert(iterator before, size_type n, const T &t)
 {
-    int offset = before - p->array;
+    int offset = int(before - p->array);
     if (n != 0) {
         const T copy(t);
         if (d->ref != 1 || d->size + n > d->alloc)
@@ -577,8 +577,8 @@ Q_TYPENAME QVector<T>::iterator QVector<T>::insert(iterator before, size_type n,
 template <typename T>
 Q_TYPENAME QVector<T>::iterator QVector<T>::erase(iterator abegin, iterator aend)
 {
-    int f = abegin - p->array;
-    int l = aend - p->array;
+    int f = int(abegin - p->array);
+    int l = int(aend - p->array);
     int n = l - f;
     detach();
     if (QTypeInfo<T>::isComplex) {