QTextStream crashes when parsing certain file with UTF-8 encoding

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Microsoft Visual C++ Runtime Library
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Debug Error!

Program: ...build-qtextstreamtext-Unnamed-Debug\debug\qtextstreamtext.exe

HEAP CORRUPTION DETECTED: after Normal block (#27107) at 0x00716898.
CRT detected that the application wrote to memory after end of heap buffer.


(Press Retry to debug the application)

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Abort   Retry   Ignore   
---------------------------

0	_free_dbg_nolock	MSVCR110D		0x6ae79e59	
1	_free_dbg	MSVCR110D		0x6ae79afe	
2	free	MSVCR110D		0x6ae7b06e	
3	QFileSelectorPrivate::~QFileSelectorPrivate	Qt5Cored		0x6b0d60c7	
4	QFileSelectorPrivate::~QFileSelectorPrivate	Qt5Cored		0x6b071cd0	
5	QFileSelectorPrivate::~QFileSelectorPrivate	Qt5Cored		0x6b06cdf3	
6	QFileSelectorPrivate::~QFileSelectorPrivate	Qt5Cored		0x6b293eb4	
7	QFileSelectorPrivate::~QFileSelectorPrivate	Qt5Cored		0x6b292652	
8	QFileSelectorPrivate::~QFileSelectorPrivate	Qt5Cored		0x6b28fe6a	
9	main	main.cpp	31	0x10416fe	
10	__tmainCRTStartup	crtexe.c	536	0x1044049	
11	mainCRTStartup	crtexe.c	377	0x104418d	
12	BaseThreadInitThunk	KERNEL32		0x7760338a	
13	__RtlUserThreadStart	ntdll_77b60000		0x77b99f72	
14	_RtlUserThreadStart	ntdll_77b60000		0x77b99f45	

1987 264
==22251== Invalid write of size 2
==22251==    at 0x51DF66F: QUtf8BaseTraits::appendUtf16(unsigned short*&, unsigned short) (qutfcodec_p.h:86)
==22251==    by 0x51DF703: int QUtf8Functions::fromUtf8<QUtf8BaseTraits, unsigned short*, unsigned char const*>(unsigned char, unsigned short*&, unsigned char const*&, unsigned char const*) (qutfcodec_p.h:194)
==22251==    by 0x51DE1DF: QUtf8::convertToUnicode(char const*, int, QTextCodec::ConverterState*) (qutfcodec.cpp:338)
==22251==    by 0x51DF199: QUtf8Codec::convertToUnicode(char const*, int, QTextCodec::ConverterState*) const (qutfcodec.cpp:636)
==22251==    by 0x4FD3749: QTextCodec::toUnicode(char const*, int, QTextCodec::ConverterState*) const (qtextcodec.h:111)
==22251==    by 0x50A4775: QTextStreamPrivate::fillReadBuffer(long long) (qtextstream.cpp:480)
==22251==    by 0x50A5046: QTextStreamPrivate::scan(QChar const**, int*, int, QTextStreamPrivate::TokenDelimiter) (qtextstream.cpp:688)
==22251==    by 0x50A654B: QTextStream::readLine(long long) (qtextstream.cpp:1578)
==22251==    by 0x4016F2: main (main.cpp:31)
==22251==  Address 0x90b03cc is 0 bytes after a block of size 32,796 alloc'd
==22251==    at 0x4C277AB: malloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==22251==    by 0x4EEE923: QArrayData::allocate(unsigned long, unsigned long, unsigned long, QFlags<QArrayData::AllocationOption>) (qarraydata.cpp:101)
==22251==    by 0x4FD3D5E: QTypedArrayData<unsigned short>::allocate(unsigned long, QFlags<QArrayData::AllocationOption>) (qarraydata.h:228)
==22251==    by 0x4FC136B: QString::QString(int, Qt::Initialization) (qstring.cpp:1460)
==22251==    by 0x51DDEFD: QUtf8::convertToUnicode(char const*, int, QTextCodec::ConverterState*) (qutfcodec.cpp:285)
==22251==    by 0x51DF199: QUtf8Codec::convertToUnicode(char const*, int, QTextCodec::ConverterState*) const (qutfcodec.cpp:636)
==22251==    by 0x4FD3749: QTextCodec::toUnicode(char const*, int, QTextCodec::ConverterState*) const (qtextcodec.h:111)
==22251==    by 0x50A4775: QTextStreamPrivate::fillReadBuffer(long long) (qtextstream.cpp:480)
==22251==    by 0x50A5046: QTextStreamPrivate::scan(QChar const**, int*, int, QTextStreamPrivate::TokenDelimiter) (qtextstream.cpp:688)
==22251==    by 0x50A654B: QTextStream::readLine(long long) (qtextstream.cpp:1578)
==22251==    by 0x4016F2: main (main.cpp:31)
==22251==