multiple definition of ms_* global variable with gcc-10

Hello,

I can't build libmemcached-1.0.18 because of multiple definition error at make step (I guess it comes from the linker):

[...]
/bin/sh ./libtool --tag=CXX --mode=link c++ -std=c++0x -O2 -fPIC -g -Wno-unknown-pragmas -Wno-pragmas -Wall -Wextra -Wno-attributes -Wvarargs -Waddress -Warray-bounds -Wchar-subscripts -Wcomment -Wctor-dtor-privacy -Wfloat-equal -Wformat=2 -Wformat-y2k -Wmaybe-uninitialized -Wmissing-field-initializers -Wlogical-op -Wnon-virtual-dtor -Wnormalized=id -Woverloaded-virtual -Wpointer-arith -Wredundant-decls -Wshadow -Wsign-compare -Wstrict-overflow=1 -Wswitch-enum -Wtrampolines -Wundef -Wunsafe-loop-optimizations -funsafe-loop-optimizations -Wc++11-compat -Wclobbered -Wunused -Wunused-result -Wunused-variable -Wunused-parameter -Wunused-local-typedefs -Wwrite-strings -Wformat-security -fwrapv -pipe -fPIE -pie -Wsizeof-pointer-memaccess -Wpacked -o clients/memaslap clients/memaslap.o clients/ms_conn.o clients/ms_setting.o clients/ms_sigsegv.o clients/ms_stats.o clients/ms_task.o clients/ms_thread.o clients/generator.o clients/execute.o -levent clients/libutilities.la libmemcached/libmemcached.la
libtool: link: c++ -std=c++0x -O2 -fPIC -g -Wno-unknown-pragmas -Wno-pragmas -Wall -Wextra -Wno-attributes -Wvarargs -Waddress -Warray-bounds -Wchar-subscripts -Wcomment -Wctor-dtor-privacy -Wfloat-equal -Wformat=2 -Wformat-y2k -Wmaybe-uninitialized -Wmissing-field-initializers -Wlogical-op -Wnon-virtual-dtor -Wnormalized=id -Woverloaded-virtual -Wpointer-arith -Wredundant-decls -Wshadow -Wsign-compare -Wstrict-overflow=1 -Wswitch-enum -Wtrampolines -Wundef -Wunsafe-loop-optimizations -funsafe-loop-optimizations -Wc++11-compat -Wclobbered -Wunused -Wunused-result -Wunused-variable -Wunused-parameter -Wunused-local-typedefs -Wwrite-strings -Wformat-security -fwrapv -pipe -fPIE -pie -Wsizeof-pointer-memaccess -Wpacked -o clients/.libs/memaslap clients/memaslap.o clients/ms_conn.o clients/ms_setting.o clients/ms_sigsegv.o clients/ms_stats.o clients/ms_task.o clients/ms_thread.o clients/generator.o clients/execute.o -levent clients/.libs/libutilities.a libmemcached/.libs/libmemcached.so -lpthread -ldl -lsasl2 -pthread
/usr/bin/ld: clients/ms_conn.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:123: multiple definition of `ms_stats'; clients/memaslap.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:123: first defined here
/usr/bin/ld: clients/ms_conn.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:120: multiple definition of `ms_global'; clients/memaslap.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:120: first defined here
/usr/bin/ld: clients/ms_conn.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:126: multiple definition of `ms_statistic'; clients/memaslap.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:126: first defined here
/usr/bin/ld: clients/ms_setting.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:126: multiple definition of `ms_statistic'; clients/memaslap.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:126: first defined here
/usr/bin/ld: clients/ms_setting.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:123: multiple definition of `ms_stats'; clients/memaslap.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:123: first defined here
/usr/bin/ld: clients/ms_setting.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:120: multiple definition of `ms_global'; clients/memaslap.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:120: first defined here
/usr/bin/ld: clients/ms_sigsegv.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:120: multiple definition of `ms_global'; clients/memaslap.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:120: first defined here
/usr/bin/ld: clients/ms_sigsegv.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:126: multiple definition of `ms_statistic'; clients/memaslap.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:126: first defined here
/usr/bin/ld: clients/ms_sigsegv.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:123: multiple definition of `ms_stats'; clients/memaslap.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:123: first defined here
/usr/bin/ld: clients/ms_task.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:120: multiple definition of `ms_global'; clients/memaslap.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:120: first defined here
/usr/bin/ld: clients/ms_task.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:123: multiple definition of `ms_stats'; clients/memaslap.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:123: first defined here
/usr/bin/ld: clients/ms_task.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:126: multiple definition of `ms_statistic'; clients/memaslap.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:126: first defined here
/usr/bin/ld: clients/ms_thread.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:123: multiple definition of `ms_stats'; clients/memaslap.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:123: first defined here
/usr/bin/ld: clients/ms_thread.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:120: multiple definition of `ms_global'; clients/memaslap.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:120: first defined here
/usr/bin/ld: clients/ms_thread.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:126: multiple definition of `ms_statistic'; clients/memaslap.o:/tmp/libmemcached-1.0.18/clients/ms_memslap.h:126: first defined here
collect2: error: ld returned 1 exit status
make[1]: *** [Makefile:4708: clients/memaslap] Error 1
make[1]: Leaving directory '/tmp/libmemcached-1.0.18'
make: *** [Makefile:3700: all] Error 2

Looking at the source code I didn't find any multiple definition of those global variables so maybe it comes from gcc-10.2.0 ?