License compliance on updating gcc runtime libraries

[<hiraku dot toyooka at cybertrust dot co dot jp>]

Hello,

I have questions about the GCC Runtime Library Exception.

When an equipment vendor distributes an update of shared gcc runtime
libraries (e.g. libgcc_s.so, libstdc++.so) to the shipped equipment
and when the equipment has applications which are dynamically linked to
older release of the shared libraries and which are being linked to
newer ones, in this case, is the exception applied to the newer ones?

I read the exception document(*) and FAQ(**).
I understood that "a work of Target Code formed by combining the Runtime
Library with Independent Modules" could be propagated as non-GPLv3
license, even if "the Runtime Library" was dynamically linked to
"Independent Modules".
I wonder if an update of the shared libraries are regarded as a part of
the "work of Target Code" or "independent library" in the above case.

Could anyone kindly tell me the intention of the exception?

(*) https://www.gnu.org/licenses/gcc-exception-3.1.en.html
(**) https://www.gnu.org/licenses/gcc-exception-3.1-faq.en.html

Best regards,
Hiraku Toyooka