问题
I'm stuck trying to figure out why my tests won't link. I'm using Boost.Build and Boost.Test from Boost 1.59 on Ubuntu. I built and installed the boost libraries from source.
I am specifying <library>/boost//unit_test_framework as part of the unit test's usage requirements. My understanding is that this should set all of the linker requirements in order to link with Boost.Test.
Unfortunately, I get a heap of linker errors for undefined references to Boost.Test components even though the link command is specifying -lboost_unit_test_framework after the test.o file.
I have a very simple example that exhibits the described behaviour:
In Jamroot:
if $(BOOST_ROOT)
{
use-project /boost : $(BOOST_ROOT) ;
}
import boost ;
boost.use-project ;
using testing ;
unit-test test
: test.cpp
: <library>/boost//unit_test_framework
;
In test.cpp:
#define BOOST_TEST_MODULE test
#include <boost/test/unit_test.hpp>
BOOST_AUTO_TEST_CASE (pass) {
}
Running b2 -d+2 gives me the compilation and linker commands that are used.
$ b2 -a -d+2
gcc.compile.c++ bin/gcc-4.9.2/debug/test.o
"g++" -ftemplate-depth-128 -O0 -fno-inline -Wall -g -std=c++11 -fPIC -DBOOST_ALL_NO_LIB -DBOOST_TEST_DYN_LINK -c -o "bin/gcc-4.9.2/debug/test.o" "test.cpp"
gcc.link bin/gcc-4.9.2/debug/test
"g++" -o "bin/gcc-4.9.2/debug/test" -Wl,--start-group "bin/gcc-4.9.2/debug/test.o" -Wl,-Bstatic -Wl,-Bdynamic -lboost_unit_test_framework -Wl,--end-group -g
bin/gcc-4.9.2/debug/test.o: In function `__static_initialization_and_destruction_0(int, int)':
/home/anthony/Development/example/test.cpp:4: undefined reference to `boost::unit_test::ut_detail::auto_test_unit_registrar::auto_test_unit_registrar(boost::unit_test::test_case*, boost::unit_test::decorator::collector&, unsigned long)'
bin/gcc-4.9.2/debug/test.o: In function `boost::unit_test::make_test_case(boost::function<void ()> const&, boost::unit_test::basic_cstring<char const>, boost::unit_test::basic_cstring<char const>, unsigned long)':
/usr/local/include/boost/test/tree/test_unit.hpp:249: undefined reference to `boost::unit_test::test_case::test_case(boost::unit_test::basic_cstring<char const>, boost::unit_test::basic_cstring<char const>, unsigned long, boost::function<void ()> const&)'
collect2: error: ld returned 1 exit status
...skipped <pbin/gcc-4.9.2/debug>test.passed for lack of <pbin/gcc-4.9.2/debug>test...
...failed updating 1 target...
回答1:
even though the link command is specifying -lboost_unit_test_framework after the test.o
Note that with the use of
-Wl,--start-group ...test.o -lboost_unit_test_framework -Wl,--end-group
the order of test.o and the library doesn't matter: because of --{start,end}-group, they are considered to be part of the same "bookshelf".
It must be that the libboost_unit_test.{a,so} does not provide the symbols that you need. Perhaps it was built with a different version of g++? (This answer may be relevant.)
Your first step should be to figure out the mangled name of the symbol(s) you are missing: add -Wl,--no-demangle to your link line.
Then you can verify that you are in fact missing the required symbol(s):
nm -A libboost_unit_test.* | grep missing_mangled_symbol
Finally, you'll need to understand why you are missing that symbol. Is there a similar but slightly different symbol defined? This command may give some clues:
nm -AC libboost_unit_test.* | grep 'boost::unit_test::test_case::test_case'
Update:
I just discovered that not only the version of g++ matters here, but also the compilation flags. Consider:
// foo.cc
#include <string>
void foo(const std::string &) { }
// t.cc
#include <string>
void foo(const std::string &);
int main() { std::string s; foo(s); }
Using recent GCC trunk:
g++ -c t.cc foo.cc
g++ t.o foo.o # success
g++ -D_GLIBCXX_USE_CXX11_ABI=0 t.cc foo.o
/tmp/ccKqZVvh.o: In function `main':
t.cc:(.text+0x1d): undefined reference to `foo(std::string const&)'
collect2: error: ld returned 1 exit status
来源：https://stackoverflow.com/questions/32420692/using-boost-build-and-boost-test-linker-errors