Reputation: 43331
I am working in Linux, Eclipse CDT, g++, with Boost library. Having existing program which uses Boost thread, I try to link it statically instead of dynamically. /usr/local/lib directory contains the following files:
libbost_thread.a
libbost_thread.so
libbost_thread.1.41.0
Dynamic linking works:
g++ -o"MyProgram" ./main.o -lboost_thread
Static linking:
g++ -static -o"MyProgram" ./main.o -lboost_thread
produces huge number of messages like:
undefined reference to `pthread_mutex_init'
How can I link statically to the Boost library?
Upvotes: 14
Views: 12415
Reputation: 10430
On Linux a dynamic library may automatically depend on other dynamic libraries so that when you link it, you get the other libraries for free. When linking statically, there is no such system and you have to specify the other libraries manually.
Upvotes: 2
Reputation: 76611
For pthread_mutex_init, you want to compile/link with -pthread option:
g++ -static -pthread -o"MyProgram" ./main.o -lboost_thread
The problem is that functions like pthread_mutex_init are in a separate library. Dynamic libraries can include the metadata for the fact that it needs the separate library (so libboost_thread.so includes the fact that it needs libpthread).
But static libraries don't have that information. So you need to provide the reference to any necessary libraries when you link statically.
As for using -pthread
instead of -lpthread
, it's slightly preferable because it not only links the necessary library, but provides any other options that should be used (such a -D_REENTRANT
to the compiler).
Upvotes: 25