base / libobjc2 link issues on FreeBSD 12

[Riccardo Mottola]

Hi,

getting a working clang+libobjc2 is a small saga now :-P
I want to update my FreeBSD 12.1 laptop too. I did the same setup I did
on my FreeBSD 11.3 workstation and it does not work, I am puzzled.

configure make:
./configure --prefix=/ --with-layout=gnustep --with-library-combo=ng-gnu-gnu

( I did not specify anything about the linker)

configure and install libobjc2 (to get the latest one, the FreeBSD
supplied version is still faulty and causes crashes)

The generated libobjc2 has:
$ ldd /System/Library/Libraries/libobjc.so
/System/Library/Libraries/libobjc.so:
        libthr.so.3 => /lib/libthr.so.3 (0x20842000)
        libcxxrt.so.1 => /lib/libcxxrt.so.1 (0x2086b000)
        libgcc_s.so.1 => /lib/libgcc_s.so.1 (0x20887000)
        libc.so.7 => /lib/libc.so.7 (0x20446000)
$

then when I configure base, the objc test fails with one missing symbol:
configure:7860: checking whether objc really works
configure:7880: clang -o conftest -g -O2  -I/Local/Library/Headers
-I/Local/Library/Headers -I/System/
Library/Headers -I/usr/local/include -I/System/Library/Headers  -x
objective-c  -L/Local/Library/Libra
ries -L/Local/Library/Libraries -L/System/Library/Libraries
-L/usr/local/lib -L/System/Library/Librari
es conftest.c -lrt -ldl  -lpthread -rdynamic -pthread -fexceptions
-fobjc-runtime=gnustep-1.8 -fblocks
 -L/home/multix/GNUstep/Library/Libraries -L/Local/Library/Libraries
-L/System/Library/Libraries -L/us
r/local/lib -lobjc -lm     >&5
In file included from conftest.c:107:
In file included from ././config/config.objc.m:2:
././config/objc-common.g:54:3: warning: assignment to Objective-C's isa
is deprecated in favor of obje
ct_setClass() [-Wdeprecated-objc-isa-usage]
  obj->isa = self;
  ^  ~~~~~~~
  object_setClass( , )
././config/objc-common.g:47:5: note: instance variable is declared here
 id isa;
    ^
1 warning generated.
configure:7880: $? = 0
configure:7880: ./conftest
ld-elf.so.1: /System/Library/Libraries/libobjc.so.4.6: Undefined symbol
"_ZNSt3__14cerrE"
configure:7880: $? = 1
configure: program exited with status 1

and now?

Riccardo