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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/111936] std::stacktrace cannot be used in a shared
 library
Date: Mon, 23 Oct 2023 14:28:36 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D111936

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to vincenzo Innocente from comment #0)
> it silently compiles with
> [innocent@patatrack01 ctest]$ c++ -O3 -Wall -pthread -fPIC -shared
> -std=3Dc++23 -lstdc++exp getStacktrace.cc
>=20
> but the symbols are undefined

This is simply because you need to list libraries after the files that depe=
nd
on them:
https://c-faq.com/lib/libsearch.html

When the linker sees -lstdc++exp there are no undefined references to any of
the symbols it provides, so the linker ignores it. Then it sees getStacktra=
ce.o
which has undefined refs but it's too late, the archive has already been
processed.

The library should be compiled as PIC though, which is a separate issue.=