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Parameter log_level allows to set the Unit Test Framework log level. Log level defines the verbosity of the testing log produced by a testing module. The verbosity ranges from a complete log, when all assertions (both successful and failing) are reported and all notifications about test units start and finish are included, to an empty log, when nothing is reported to a testing log stream.

Log level is set to one of the predefined levels which are organized hierarchically, where each level includes all the messages on that level as well as all the messages from levels below. Levels are identified by string names, which are listed next.

Acceptable values

Following is the list of enumeration log_level names ordered from higher to lower level. Thus each level includes messages on that level as well as all the messages on levels defined below.


Included messages

all (default for JUNIT)

All log messages including the passed assertions notification


The same as all


Test units start/finish notifications


User generated messages (using BOOST_TEST_MESSAGE tool)


Messages describing failed assertion on WARN level ( BOOST_TEST_WARN / BOOST_WARN_... tools)

error (default for HRF and XML)

Messages describing failed assertion on CHECK level (BOOST_TEST / BOOST_CHECK_... tools)


Messages reporting uncaught C++ exception


Messages reporting system originated non-fatal errors. For example, timeout or floating point exception.


Messages reporting user or system originated fatal errors. For example, memory access violation. Also all the messages describing failed assertion on REQUIRE level (BOOST_TEST_REQUIRE / BOOST_REQUIRE_... tools)


No messages are reported.

[Caution] Caution

the JUNIT log format does not accept the log level to change: anything specified by log_level will be ignored for the JUNIT format.

Command line syntax
Environment variable