Question

I am trying to run a newly compiled binary on some oldish 32bits RedHat distribution.
The binary is compiled C (not++) on a CentOS 32bits VM running libc v2.12.

RedHat complains about libc version:

error while loading shared libraries: requires glibc 2.5 or later dynamic linker

Since my program is rather simplistic, It is most likely not using anything new from libc.

Is there a way to reduce libc version requirement

Answer 1

An untested possible solution

What is “error while loading shared libraries: requires glibc 2.5 or later dynamic linker”?

The cause of this error is the dynamic binary (or one of its dependent
shared libraries) you want to run only has .gnu.hash section, but the
ld.so on the target machine is too old to recognize .gnu.hash; it only
recognizes the old-school .hash section.

This usually happens when the dynamic binary in question is built
using newer version of GCC. The solution is to recompile the code with
either -static compiler command-line option (to create a static
binary), or the following option:

-Wl,--hash-style=both

This tells the link editor ld to create both .gnu.hash and .hash
sections.

According to ld documentation here, the old-school .hash section
is the default, but the compiler can override it. For example, the GCC
(which is version 4.1.2) on RHEL (Red Hat Enterprise Linux) Server
release 5.5 has this line:

$ gcc -dumpspecs
....
*link:
%{!static:--eh-frame-hdr} %{!m32:-m elf_x86_64} %{m32:-m elf_i386} --hash-style=gnu   %{shared:-shared}   ....
                                                                   ^^^^^^^^^^^^^^^^
...

For more information, see here.