Build fails due to ambiguous 'ToZtring(size_t)' at CommandLine_Parser.cpp:215:151.

Except form build log:
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g++ -DPACKAGE_NAME=\"mediainfo\" -DPACKAGE_TARNAME=\"mediainfo\" -DPACKAGE_VERSION=\"0.7.73\" -DPACKAGE_STRING=\"mediainfo\ 0.7.73\" -DPACKAGE_BUGREPORT=\"\" -DPACKAGE_URL=\"\" -DPACKAGE=\"mediainfo\" -DVERSION=\"0.7.73\" -DSTDC_HEADERS=1 -DHAVE_SYS_TYPES_H=1 -DHAVE_SYS_STAT_H=1 -DHAVE_STDLIB_H=1 -DHAVE_STRING_H=1 -DHAVE_MEMORY_H=1 -DHAVE_STRINGS_H=1 -DHAVE_INTTYPES_H=1 -DHAVE_STDINT_H=1 -DHAVE_UNISTD_H=1 -DHAVE_DLFCN_H=1 -DLT_OBJDIR=\".libs/\" -DUNICODE=1 -I. -I../../../Source -I../../../../MediaInfoLib/Source -I../../../../ZenLib/Source    -O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches  -m31 -march=z9-109 -mtune=z10 -O2 -DUNICODE  -DUNICODE  -c -o Core.o `test -f '../../../Source/Common/Core.cpp' || echo './'`../../../Source/Common/Core.cpp
../../../Source/CLI/CommandLine_Parser.cpp: In function 'void CallBack_Set(Core&, void*)':
../../../Source/CLI/CommandLine_Parser.cpp:215:151: error: call of overloaded 'ToZtring(size_t)' is ambiguous
     MI.Menu_Option_Preferences_Option(__T("Event_CallBackFunction"), __T("CallBack=memory://")+ZenLib::Ztring::ToZtring((size_t)Event_CallBackFunction));
                                                                                                                                                       ^
../../../Source/CLI/CommandLine_Parser.cpp:215:151: note: candidates are:
In file included from ../../../Source/CLI/Config.h:12:0,
                 from ../../../Source/CLI/CommandLine_Parser.h:14,
                 from ../../../Source/CLI/CommandLine_Parser.cpp:16:
/usr/include/ZenLib/Ztring.h:303:19: note: static ZenLib::Ztring ZenLib::Ztring::ToZtring(ZenLib::int8s, ZenLib::int8u)
     static Ztring ToZtring  (const int8s    I, int8u Radix=10)                   {return Ztring().From_Number(I, Radix);};
                   ^
/usr/include/ZenLib/Ztring.h:304:19: note: static ZenLib::Ztring ZenLib::Ztring::ToZtring(ZenLib::int8u, ZenLib::int8u)
     static Ztring ToZtring  (const int8u    I, int8u Radix=10)                   {return Ztring().From_Number(I, Radix);};
                   ^
/usr/include/ZenLib/Ztring.h:305:19: note: static ZenLib::Ztring ZenLib::Ztring::ToZtring(ZenLib::int16s, ZenLib::int8u)
     static Ztring ToZtring  (const int16s   I, int8u Radix=10)                   {return Ztring().From_Number(I, Radix);};
                   ^
/usr/include/ZenLib/Ztring.h:306:19: note: static ZenLib::Ztring ZenLib::Ztring::ToZtring(ZenLib::int16u, ZenLib::int8u)
     static Ztring ToZtring  (const int16u   I, int8u Radix=10)                   {return Ztring().From_Number(I, Radix);};
                   ^
/usr/include/ZenLib/Ztring.h:307:19: note: static ZenLib::Ztring ZenLib::Ztring::ToZtring(ZenLib::int32s, ZenLib::int8u)
     static Ztring ToZtring  (const int32s   I, int8u Radix=10)                   {return Ztring().From_Number(I, Radix);};
                   ^
/usr/include/ZenLib/Ztring.h:308:19: note: static ZenLib::Ztring ZenLib::Ztring::ToZtring(ZenLib::int32u, ZenLib::int8u)
     static Ztring ToZtring  (const int32u   I, int8u Radix=10)                   {return Ztring().From_Number(I, Radix);};
                   ^
/usr/include/ZenLib/Ztring.h:309:19: note: static ZenLib::Ztring ZenLib::Ztring::ToZtring(ZenLib::int64s, ZenLib::int8u)
     static Ztring ToZtring  (const int64s   I, int8u Radix=10)                   {return Ztring().From_Number(I, Radix);};
                   ^
/usr/include/ZenLib/Ztring.h:310:19: note: static ZenLib::Ztring ZenLib::Ztring::ToZtring(ZenLib::int64u, ZenLib::int8u)
     static Ztring ToZtring  (const int64u   I, int8u Radix=10)                   {return Ztring().From_Number(I, Radix);};
                   ^
/usr/include/ZenLib/Ztring.h:311:19: note: static ZenLib::Ztring ZenLib::Ztring::ToZtring(ZenLib::int128u, ZenLib::int8u)
     static Ztring ToZtring  (const int128u  I, int8u Radix=10)                   {return Ztring().From_Number(I, Radix);};
                   ^
/usr/include/ZenLib/Ztring.h:312:19: note: static ZenLib::Ztring ZenLib::Ztring::ToZtring(ZenLib::float32, ZenLib::int8u)
     static Ztring ToZtring  (const float32  F, int8u AfterComma=3)               {return Ztring().From_Number(F, AfterComma);};
                   ^
/usr/include/ZenLib/Ztring.h:313:19: note: static ZenLib::Ztring ZenLib::Ztring::ToZtring(ZenLib::float64, ZenLib::int8u)
     static Ztring ToZtring  (const float64  F, int8u AfterComma=3)               {return Ztring().From_Number(F, AfterComma);};
                   ^
/usr/include/ZenLib/Ztring.h:314:19: note: static ZenLib::Ztring ZenLib::Ztring::ToZtring(ZenLib::float80, ZenLib::int8u)
     static Ztring ToZtring  (const float80  F, int8u AfterComma=3)               {return Ztring().From_Number(F, AfterComma);};
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Failed build:
http://s390.koji.fedoraproject.org/koji/taskinfo?taskID=1776664


This seems to be caused by missing size_t conversion in Ztring in libzen(Ztring& Ztring::From_Number (const size_t I, int8u Radix)), as it's build conditionally. Making it unconditional seems to fix this issue. I have build mediainfo with patched libzen on x86_64 and s390(x) successfully, but haven't done any further testing.