Programs with Boost Dependency Fail to Compile in Qt Creator - boost

Question

I get undefined reference errors to various things in the boost:: namespace if I attempt to compile programs that use any parts of Boost Libraries in Qt Creator 2.5.2. At first I thought it's because I was mixing static Boost libraries with shared Qt libraries, so I recompiled Boost with link=shared runtime-link=shared build option, but the problem remains. I then started a Non-Qt, Plain C++ project that consists of nothing more than a main.cpp containing a slightly modified Boost test program:
// main.cpp, cin-less version of
// http://www.boost.org/doc/libs/1_51_0/more/getting_started/windows.html#test-your-program
#include <iostream>
#include <string>
#include <boost/regex.hpp>
int main() {
std::string headerLines = "To: George Shmidlap\n" \
"From: Rita Marlowe\n" \
"Subject: Will Success Spoil Rock Hunter?\n" \
"---\n" \
"See subject.\n";
boost::regex pat( "^Subject: (Re: |Aw: )*(.*)" );
boost::smatch matches;
std::string::iterator newLinePos = std::find(headerLines.begin(), headerLines.end(), '\n');
std::string::iterator startPos = headerLines.begin();
while(newLinePos != headerLines.end()) {
if (boost::regex_match(std::string(startPos, newLinePos++), matches, pat)) {
std::cout << "\nRegex Match: " << matches[2];
}
startPos = newLinePos;
newLinePos = std::find(startPos, headerLines.end(), '\n');
}
char temp[3];
std::cin.getline(temp, 2);
return 0;
}
Project file:
TEMPLATE = app
CONFIG += console
CONFIG -= qt
SOURCES += main.cpp
Debug {
LIBS += -lboost_regex-mgw46-mt-d-1_51
}
release {
LIBS += -lboost_regex-mgw46-mt-1_51
}
Compiling the above project from within Qt Creator, or using mingw32-make in command line, gives:
E:\BoostTest-483-MinGW_Debug\debug\main.o:-1: In function `ZN5boost13match_resultsIN9__gnu_cxx17__normal_iteratorIPKcSsEESaINS_9sub_matchIS5_EEEE17raise_logic_errorEv':
c:\tdm-mingw32\include\boost\regex\v4\match_results.hpp:562: error: undefined reference to `boost::throw_exception(std::exception const&)'
E:\BoostTest-483-MinGW_Debug\debug\main.o:-1: In function `ZN5boost9re_detail12perl_matcherIN9__gnu_cxx17__normal_iteratorIPKcSsEESaINS_9sub_matchIS6_EEENS_12regex_traitsIcNS_16cpp_regex_traitsIcEEEEE14construct_initERKNS_11basic_regexIcSD_EENS_15regex_constants12_match_flagsE':
c:\tdm-mingw32\include\boost\regex\v4\perl_matcher_common.hpp:55: error: undefined reference to `boost::throw_exception(std::exception const&)'
[etc...]
Compiling main.cpp from command line, without Qt Creator or mingw32-make, works just fine:
E:\BoostTest>g++ -s -O3 main.cpp -o main.exe -lboost_regex-mgw46-mt-1_51
E:\BoostTest>main.exe
Regex Match: Will Success Spoil Rock Hunter?
E:\BoostTest>g++ -s -O3 main.cpp -o main-dbg.exe -lboost_regex-mgw46-mt-d-1_51
E:\BoostTest>main-dbg.exe
Regex Match: Will Success Spoil Rock Hunter?
Tested with:
TDM-MinGW32 (MinGW 4.6.1)
My own builds of MinGW:
MinGW 4.6.3 with dwarf2 exceptions handling
MinGW 4.6.3 with SJLJ exceptions handling
Boost Libraries 1.51.0 (built from source with each of the above compiler builds, static and shared libraries)
Qt Framework 4.8.3 for MinGW, precompiled binaries.
Qt Creator 2.5.2 for Windows.
I've checked Qmake's makescpecs configuration files, among other things, but still cannot figure out the root of the problem. Any ideas?

Answer 1

This is most likely far too late to help you, but I've just had to figure this one out today. I too am using mingw32 and Qt and had the same undefined reference.
I first resolved it by adding the following in `some file', based on another StackOverflow question:
namespace boost
{
void throw_exception(std::exception const &e) { assert(false); }
}
However I actually wanted to throw an exception, so changed the assert(false); to a throw e;. That immediately threw up the compile error:
error: exception handling disabled, use -fexceptions to enable
...which gives a clue.
The trick turned out to be adding CONFIG += exceptions (along with console so cout/printf etc. actually do anything, that was a real pain!) to my qmake file. I have no idea what is really going on here, maybe most Linux distros add something special to the qmake spec files or whatever.