What is the purpose of the /lib/libgcc_s.so.1 library?

[dnb]

In FreeBSD Clang has the following dynamic object dependencies:

# ldd /usr/bin/clang | grep gcc
libgcc_s.so.1 => /lib/libgcc_s.so.1

Despite numerous mentions of this library, I still could not understand what the true purpose of this library is in FreeBSD? Why does Clang depend on this library? Could someone explain in simple terms (or provide a link to the documentation).

 

[cracauer@]

It contains code needed for startup. Code that is needed even if you don't use libc.

 

[VladiBG]

google search returns: https://gcc.gnu.org/onlinedocs/gccint/Libgcc.html

 

[Erichans]

I get the impression (but may miss the essence of its use and meaning for the FreeBSD-Clang toolchain) that it's about a part of GCC/GCC-origins that seems to be particularly hard to get rid of:

[llvm-branch-commits] [clang] bcc526e - [PATCH] Prefer gcc toolchains with libgcc_s.so when not static linking libgcc

⚙ D106703 [libunwind] adds a way to synthesise libgcc

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