Boost.Test linker error - undefined reference to 'main'

[Jestine Paul]

 I get the following error while linking with libboost_unit_test_framework.

user23@Mycomp:~/scrapbook$ g++ unit_test_example1.cpp -lboost_unit_test_framework
/usr/lib/gcc/i486-linux-gnu/4.1.3/../../../../lib/crt1.o: In function `_start':
(.text+0x18): undefined reference to `main'
collect2: ld returned 1 exit status

I am using this example http://beta.boost.org/doc/libs/1_33_1/libs/test/example/unit_test_example1.cpp

But, it works fine while linking with the static library using the following command.
      g++ test3.cpp /usr/lib/libboost_unit_test_framework.a

unit_test_example1.cpp :-
// Boost.Test
#include <boost/test/unit_test.hpp>
using boost::unit_test::test_suite;

// most frequently you implement test cases as a free functions
void free_test_function()
{
    // reports 'error in "free_test_function": test 2 == 1 failed'
    BOOST_CHECK(2 == 1); // non-critical test => continue after failure

    int* p = (int*)0;
    *p = 0;
}

test_suite*
init_unit_test_suite( int, char* [] ) {
    test_suite* test= BOOST_TEST_SUITE( "Unit test example 1" );

    // this example will pass cause we know ahead of time number of expected failures
    test->add( BOOST_TEST_CASE( &free_test_function ), 1 /* expected one error */ );

    return test;
}

// EOF

[Guido U. Draheim 2007 (guidod-2007-)]

The boost documentation is outdated. Please read
    /usr/include/boost/test/unit_test.hpp
which defines "main" (i.e. it is not a real symbol in the lib*.so).
You will find the requirement for two precompiler defines
   if defined(BOOST_TEST_DYN_LINK) && defined(BOOST_TEST_MAIN)

Note: earlier boost libraries did not require those defines,
and I did only came across this as ALL my programs did
not compile anymore after upgrading the operating system.
(actually to Ubuntu 08.04 w/ boost 1.34.1).

However, blame the boost developers, not the packagers.