https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110572
Bug ID: 110572
Summary: ld.lld: error: duplicate symbol:
std::type_info::operator==(std::type_info const&)
const
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
Assignee: unassigned at gcc dot gnu.org
Reporter: arndtthomas at gmx dot de
Target Milestone: ---
Created attachment 55489
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=55489&action=edit
example to reproduce the error
I've filed the issue since it's a problem with libstdc++/tinfo.o.
It seems there is a missing inline if macro __GXX_TYPEINFO_EQUALITY_INLINE is
unset or set to 1.
It happens if clang is used under mingw-w64 in combination with the libstdc++
(msys2 default).
Since gcc defines the macro explicitly (built-in) to
_GXX_TYPEINFO_EQUALITY_INLINE=0 (see gcc/config/i386/cygming.h).
Clang doesn't define this macro at all, so it gets defined within typeinfo
while compiling user code. Thus there are one operator== defined within tinfo.o
and another within the user archive.
During linking the following error pops up:
ld.lld: error: duplicate symbol: std::type_info::operator==(std::type_info
const&) const
>>> defined at ../../../../libstdc++-v3/libsupc++/tinfo.cc:38
>>> libstdc++.a(tinfo.o)
>>> defined at libclang_lld_error.a(comp_unit.o)
clang++: error: linker command failed with exit code 1 (use -v to see
invocation)
Here is the full example to reproduce:
https://github.com/msys2/MINGW-packages/issues/17730
I fully agree, it's a issue which is more related to mingw-w64 and clang but
the root cause is unfortunately the libstdc++.
