How to link to a different libc file?

c gcc linker ld libc
Neeladri Vishweswaran picture Neeladri Vishweswaran · Apr 28, 2010 · Viewed 15.2k times · Source

I want to supply the shared libraries along with my program rather than using the target system's due to version differences.

ldd says my program uses these shared libs:

linux-gate.so.1 =>  (0xf7ef0000)**(made by kernel)**  
libc.so.6 => /lib32/libc.so.6 (0xf7d88000)**(libc-2.7.so)**  
/lib/ld-linux.so.2 (0xf7ef1000)**(ld-2.7.so)**

I have successfully linked ld-xxx.so by compiling with:

gcc -std=c99 -D_POSIX_C_SOURCE=200112L -O2 -m32 -s -Wl,-dynamic-linker,ld-2.7.so myprogram.c

But I have not managed to successful link libc-xxx.so. How can I do that ?

Answer

Neeladri Vishweswaran picture Neeladri Vishweswaran · Apr 30, 2011

I found out how to do it:

rpath specifies where the provided libraries are located. This folder should contain: libc.so.6, libdl.so.2, libgcc_s.so.1 and maybe more. Check with strace to find out which libraries your binary file uses.

ld.so is the provided linker

gcc -Xlinker -rpath=/default/path/to/libraries -Xlinker -I/default/path/to/libraries/ld.so program.c

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