/usr/lib/x86_64-linux-gnu/libQt5Test.prl is in qtbase5-gles-dev 5.5.1+dfsg-16ubuntu6.
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1 2 3 4 5 6 | QMAKE_PRL_BUILD_DIR = /build/qtbase-opensource-src-gles-MfcfWU/qtbase-opensource-src-gles-5.5.1+dfsg/src/testlib
QMAKE_PRO_INPUT = testlib.pro
QMAKE_PRL_TARGET = libQt5Test.so.5.5.1
QMAKE_PRL_CONFIG = lex yacc exceptions depend_includepath testcase_targets import_plugins import_qpa_plugin qt warn_on release link_prl incremental shared qpa no_mocdepend release qt_no_framework linux unix posix gcc compile_examples system-sqlite qpa largefile nostrip precompile_header use_gold_linker enable_new_dtags sse2 sse3 ssse3 sse4_1 sse4_2 avx avx2 prefix_build force_independent create_prl link_prl prepare_docs qt_docs_targets no_private_qt_headers_warning QTDIR_build testcase_exceptions qt_example_installs warning_clean exceptions qmake_cache target_qt need_fwd_pri qt_install_module c++11 hide_symbols bsymbolic_functions qt_install_headers create_cmake compiler_supports_fpmath create_pc create_libtool explicitlib have_target dll thread moc resources
QMAKE_PRL_VERSION = 5.5.1
QMAKE_PRL_LIBS = -lQt5Core -lpthread
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