Collegamento a boost barfs con 'riferimento indefinito a `boost :: system :: get_system_category()'

Question

Ho problemi a collegare staticamente un'app che utilizza le librerie boost 1.35. Sto usando un box Lenny di debian di linux, con G ++ 4.3.2. Il collegamento senza - statico funziona senza intoppi.

In particolare,

g++ -Wall -Wextra -pedantic -ggdb3 -O0 -static -l boost_thread-mt -lboost_system-mt -lboost_program_options-mt -lssl -lpthread -l crypto main.o comandos.o utils.o tunnel.o opciones.o decode.o sysutils.o -o sapp 

main.o: In function `__static_initialization_and_destruction_0': 
/usr/include/boost/system/error_code.hpp:204:undefined reference to `boost::system::get_system_category()' 
/usr/include/boost/system/error_code.hpp:205: undefined reference to `boost::system::get_posix_category()' 
/usr/include/boost/system/error_code.hpp:209: undefined reference to `boost::system::get_posix_category()' 
/usr/include/boost/system/error_code.hpp:210: undefined reference to `boost::system::get_system_category()' 

sto collegando contro boost_system-mt, che si trova sulla mia macchina in/usr/lib. La stessa cosa accade se collego contro la versione non multithread-safe di boost_system (-lboost_system)

sarraga@saggy:~/sapp/src$ ls -al /usr/lib/libboost_system*a 
-rw-r--r-- 1 root root 23506 2008-05-23 05:32 /usr/lib/libboost_system.a 
lrwxrwxrwx 1 root root 17 2010-08-26 19:10 /usr/lib/libboost_system-gcc42-1_35.a -> libboost_system.a 
lrwxrwxrwx 1 root root 20 2010-08-26 19:10 /usr/lib/libboost_system-gcc42-mt-1_35.a -> libboost_system-mt.a 
-rw-r--r-- 1 root root 23506 2008-05-23 05:32 /usr/lib/libboost_system-mt.a 

E trovo i simboli non risolti ci

sarraga@saggy:~/sapp/src$ nm -C /usr/lib/libboost_system-mt.a | grep 'T.*get.*category' 
00000050 T boost::system::get_posix_category() 
000000b0 T boost::system::get_system_category() 

Uno strace mostra che il linker si apre la biblioteca

sarraga@saggy:~/sapp/src$ strace -f make 2>&1 | grep boost_system 
[pid 15016] execve("/usr/bin/g++", ["g++", "-Wall", "-Wextra", "-pedantic", "-ggdb3", "-O0", "-static", "-l", "boost_thread-mt", "-lboost_system-mt", "-lboost_program_options-mt", "-lssl", "-lpthread", "-l", "crypto", "main.o", ...], [/* 41 vars */] <unfinished ...> 
... 
[pid 15018] open("/usr/lib/gcc/i486-linux-gnu/4.3.2/../../../../lib/libboost_system-mt.a", O_RDONLY|O_LARGEFILE) = 8 

Si tratta di un'installazione standard pacchetto di spinta in debian,

sarraga@saggy:~/sapp/src$ dpkg -l | grep boos 
ii libboost-date-time1.35-dev   1.35.0-5     set of date-time libraries based on generic programming 
ii libboost-date-time1.35.0    1.35.0-5     set of date-time libraries based on generic programming 
ii libboost-filesystem1.35-dev   1.35.0-5     filesystem operations (portable paths, iteration over d 
ii libboost-filesystem1.35.0   1.35.0-5     filesystem operations (portable paths, iteration over d 
ii libboost-graph1.35-dev    1.35.0-5     generic graph components and algorithms in C++ 
ii libboost-graph1.35.0     1.35.0-5     generic graph components and algorithms in C++ 
ii libboost-iostreams1.35-dev   1.35.0-5     Boost.Iostreams Library development files 
ii libboost-iostreams1.35.0    1.35.0-5     Boost.Iostreams Library 
ii libboost-program-options1.35-dev  1.35.0-5     program options library for C++ 
ii libboost-program-options1.35.0  1.35.0-5     program options library for C++ 
ii libboost-python1.35-dev    1.35.0-5     Boost.Python Library development files 
ii libboost-python1.35.0    1.35.0-5     Boost.Python Library 
ii libboost-regex1.35-dev    1.35.0-5     regular expression library for C++ 
ii libboost-regex1.35.0     1.35.0-5     regular expression library for C++ 
ii libboost-serialization1.35-dev  1.35.0-5     serialization library for C++ 
ii libboost-serialization1.35.0   1.35.0-5     serialization library for C++ 
ii libboost-signals1.35-dev    1.35.0-5     managed signals and slots library for C++ 
ii libboost-signals1.35.0    1.35.0-5     managed signals and slots library for C++ 
ii libboost-system1.35-dev    1.35.0-5     Operating system (e.g. diagnostics support) library 
ii libboost-system1.35.0    1.35.0-5     Operating system (e.g. diagnostics support) library 
ii libboost-test1.35-dev    1.35.0-5     components for writing and executing test suites 
ii libboost-test1.35.0     1.35.0-5     components for writing and executing test suites 
ii libboost-thread1.35-dev    1.35.0-5     portable C++ multi-threading 
ii libboost-thread1.35.0    1.35.0-5     portable C++ multi-threading 
ii libboost-wave1.35-dev    1.35.0-5     C99/C++ preprocessor library 
ii libboost-wave1.35.0     1.35.0-5     C99/C++ preprocessor library 
ii libboost1.35-dev      1.35.0-5     Boost C++ Libraries development files 
ii libboost1.35-doc      1.35.0-5     Boost.org libraries documentation 

Sono sicuro che mi manca uno stupido dettaglio, ma non riesco a trovarlo. Qualcuno aiuta?

Answer 1

Durante il collegamento statico il linker si aspetta che le librerie vengano dopo i file che contengono riferimenti a esse. È necessario spostare i file .o prima dei flag -l. L'idea è che i file che vengono in seguito "compilano" i riferimenti contenuti nei file precedenti - poiché i file .o sono ultimi, il linker si aspetta che riempiano eventuali simboli mancanti in boost_system piuttosto che viceversa. Quando si collega dinamicamente, l'ordine non ha importanza perché non risolve un simbolo fino a quando non viene utilizzato per la prima volta in fase di esecuzione (ea quel punto conosce l'elenco completo di librerie in cui cercare i simboli).