/usr/lib/x86_64-linux-gnu/libQtSvg.prl is in libqt4-dev 4:4.8.1-0ubuntu4.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 | QMAKE_PRO_INPUT = svg.pro
QMAKE_PRL_TARGET = libQtSvg.so.4.8.1
QMAKE_PRL_DEFINES = QT_SHARED
QMAKE_PRL_CONFIG = lex yacc warn_on uic resources qt warn_on release incremental link_prl gdb_dwarf_index def_files_disabled exceptions no_mocdepend release stl qt_no_framework system-sqlite release shared dll largefile stl precompile_header mmx 3dnow sse sse2 sse3 ssse3 sse4_1 sse4_2 avx dylib create_prl link_prl depend_includepath QTDIR_build nostrip use_libmysqlclient_r qt_install_headers qt warn_on depend_includepath qmake_cache target_qt hide_symbols bsymbolic_functions create_pc create_libtool explicitlib moc thread shared dll
QMAKE_PRL_VERSION = 4.8.1
QMAKE_PRL_LIBS =
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