shared-libraries

I need to use an alternate glibc version, newer than the one installed on my system ( 2.18 vs 2.15 ). Several related issues are covered here and here . The specific question I'm asking here is the following: I set up the library path of the new dynamic linker ( ld-2.18.so ) so that the new libc ( libc-2.18.so ) is found ahead of the old libc ( libc-2.15.so ). However, when I try to run a program with the new ld , the old version of libc is picked up, generating a SEGV . Why is that happening? Note: I know this can be fixed by using --rpath at compile time or LD_LIBRARY_PATH at run time.

I am putting together a makefile for a project i am working on. I have an executable and a shared library in the project. Both use some of the same source files which get compiled separately into object files. To be able to use these objects in the shared library I need to use the -fPIC (position independent code) flag in gcc. Are there any implications of compiling objects with -fPIC that get used in a executable? Compiling position-independent code when not necessary is a performance drag on some platforms (most notably, the register-starved x86 architecture, because PIC takes away a

The C++ standard 3.6.3 states Destructors for initialized objects of static duration are called as a result of returning from main and as a result of calling exit On windows you have FreeLibrary and linux you have dlclose to unload a dynamically linked library. And you can call these functions before returning from main. A side effect of unloading a shared library is that all destructors for static objects defined in the library are run. Does this mean it violates the C++ standard as these destructors have been run prematurely ? They are only run prematurely if you go to great effort to do so

I recently installed the hdf5 library on an ubuntu machine, and am now having trouble linking to the exported functions. I wrote a simple test script readHDF.cpp to explain the issue: #include <hdf5.h> int main(int argc, char * argv[]) { hid_t h5_file_id = H5Fopen(argv[1], H5F_ACC_RDWR, H5P_DEFAULT); return 0; } The compile command is g++ -Wl,-rpath,$HOME/hdf5/lib -I$HOME/hdf5/include \ -L$HOME/hdf5/lib -l:$HOME/hdf5/lib/libhdf5.so readHDF.cpp which returns the following error /tmp/cc6DXdxV.o: In function `main': readHDF.cpp:(.text+0x1f): undefined reference to `H5check_version' readHDF.cpp:(

I'm trying to use sprof to profile some software (ossim) where almost all the code is in a shared library. I've generated a profiling file, but when I run sprof, I get the following error: > sprof /home/eca7215/usr/lib/libossim.so.1 libossim.so.1.profile -p > log Inconsistency detected by ld.so: dl-open.c: 612: _dl_open: Assertion `_dl_debug_initialize (0, args.nsid)->r_state == RT_CONSISTENT' failed! The instructions I was following said that I needed libc version at least 2.5-34, I have libc version 2.12.2 (Gentoo, kernel 2.6.36-r5). I can't find any explanation as to what the error means or