gcc shared library failed linking to glibc

Question

I\'m writing a simple C shared library using Eclipse CDT under Linux 64bit.

The code has one reference to the rand() function in the

Answer 1

On x86_64 architecture gcc requires you to use -fPIC i.e Position Independent Code by default.

The underlying reason for the error is that the relocation type for the symbol rand is of type R_X86_64_PC32 which means that it is PC relative and should lie within 32bit offset from the following instruction.

But the current architecture is of x86_64 type which means that it can lie anywhere within the 64bit address space.

So the dynamic linker actually can not link a symbol with such a relocation type.

Either you have to use -fPIC or compile your code using the -mcmodel=large which will actually make the relocation type to R_X86_64_64.

For more details on how linking is done refer to this great blog by Eli Bendersky