kdelibs3-3.5.10-105.fc33 fails to build in Fedora 33:

/bin/sh ../libtool --silent  --tag=CXX   --mode=compile g++ -DHAVE_CONFIG_H -I. -I.. -I../dcop -I../kdecore -I../kio/kssl -I../kjs -I../kio -I../dcop -I../libltdl -I../dcop -I../libltdl -I../kdefx -I../kdecore -I../kdecore -I../kdecore/network -I../kdeui -I../kio -I../kio/kio -I../kio/kfile -I.. -I/usr/lib64/qt-3.3/include -I. -I/usr/include/kde  -Drestrict= -I/usr/include/OpenEXR -pthread   -DQT_THREAD_SUPPORT  -D_REENTRANT  -DNDEBUG -DNO_DEBUG -O2 -O2 -flto -ffat-lto-objects -fexceptions -g -grecord-gcc-switches -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -fstack-protector-strong -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection -Wno-deprecated-declarations -Wno-narrowing -std=gnu++98 -fno-exceptions -fno-check-new -fno-common  -DQT_CLEAN_NAMESPACE -DQT_NO_ASCII_CAST -DQT_NO_STL -DQT_NO_COMPAT -DQT_NO_TRANSLATION -fexceptions -c -o jp2.lo jp2.cpp
[...]
jp2.cpp: In function 'void kimgio_jp2_write(QImageIO*)':
jp2.cpp:246:31: error: 'dup' was not declared in this scope
  246 |   stream = jas_stream_fdopen( dup( qf->handle() ), "w" );
      |                               ^~~

A difference between passing and failing build root is at <https://koschei.fedoraproject.org/build/8619516> An upgrade of qt3-devel from 
3.3.8b-80.fc32 to 3.3.8b-83.fc33 is suspicious.