Ah, you are using the system python that was built with gcc, but you want to build sage with clang/clang++.
In python, setting CC will override the compiler used for building extension modules, but it will not override the linker used for building an extension module. What happens here is a file is compiled with `-fopenmp` with clang (meaning it needs to be linked with libomp from LLVM), but linked with `-fopenmp` with gcc (meaning it links to libgomp from GNU). To fix this, you'll have to set env variable LDSHARED="clang -pthread -shared" Isuru Fernando On Tue, Aug 17, 2021 at 1:52 PM Kazuyoshi Furutaka < furutaka.kazuyo...@gmail.com> wrote: > > > 2021年8月17日(火) 17:05 Isuru Fernando <isu...@gmail.com>: > >> Did you rebuild python? You might have to do "make distclean". >> >> Isuru >> >> > I believe I didn't. > > excerpt from the config.log... > >> >> 4360 ## -------------------------------------------------------- ## >> 4361 ## Checking whether SageMath should install SPKG python3... ## >> 4362 ## -------------------------------------------------------- ## >> 4363 configure:33651: checking whether any of bzip2 xz libffi is >> installed as or will be installed as SPKG >> 4364 configure:33660: result: no >> 4365 configure:33664: checking for python3 >= 3.7.0, < 3.10.0 with >> modules sqlite3, ctypes, math, hashlib, crypt, socket, zlib, distutils.core >> 4366 configure:34331: result: >> 4367 configure:34355: checking ... whether /usr/bin/python3 is good >> 4368 CC=clang CXX=clang++ -std=gnu++11 conftest_venv/bin/python3 >> conftest.py --verbose build --build-base=conftest.dir >> 4369 running build >> 4370 running build_ext >> 4371 building 'config_check_distutils' extension >> 4372 creating conftest.dir >> 4373 creating conftest.dir/temp.linux-x86_64-3.9 >> 4374 clang -Wno-unused-result -Wsign-compare >> -DDYNAMIC_ANNOTATIONS_ENABLED=1 -DNDEBUG -O2 -fexceptions -g >> -grecord-gcc-switches -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOU >> 4374 RCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -fstack-protector-strong -m64 >> -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection >> -fcf-protection -D_GNU_SOURCE -fPIC -fwrapv -O >> 4374 2 -fexceptions -g -grecord-gcc-switches -pipe -Wall >> -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS >> -fstack-protector-strong -m64 -mtune=generic -fasyn >> 4374 chronous-unwind-tables -fstack-clash-protection -fcf-protection >> -D_GNU_SOURCE -fPIC -fwrapv -O2 -fexceptions -g -grecord-gcc-switches -pipe >> -Wall -Werror=format-security -Wp,-D_ >> 4374 FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS >> -fstack-protector-strong -m64 -mtune=generic -fasynchronous-unwind-tables >> -fstack-clash-protection -fcf-protection -D_GNU_SOURCE -fPIC >> 4374 -fwrapv -Dlinux -I/usr/include -fPIC >> -I/home/furutaka/work/sage/sage-9.4.rc2-git-clang2/conftest_venv/include >> -I/usr/include/python3.9 -c conftest.c -o conftest.dir/temp.linux- >> 4374 x86_64-3.9/conftest.o >> 4375 creating conftest.dir/lib.linux-x86_64-3.9 >> 4376 gcc -pthread -shared -Wl,-z,relro -Wl,--as-needed -Wl,-z,now -g >> -Wl,-z,relro -Wl,--as-needed -Wl,-z,now -g -Dlinux -I/usr/include >> conftest.dir/temp.linux-x86_64-3.9/conftest.o - >> 4376 L/usr/lib64 -o conftest.dir/lib.linux-x86_64-3.9/ >> config_check_distutils.cpython-39-x86_64-linux-gnu.so >> 4377 CC=clang CXX=clang++ -std=gnu++11 conftest_venv/bin/python3 >> conftest.py --verbose build --build-base=conftest.dir >> 4378 running build >> 4379 running build_ext >> 4380 building 'config_check_distutils_cxx' extension >> 4381 creating conftest.dir >> 4382 creating conftest.dir/temp.linux-x86_64-3.9 >> 4383 clang -Wno-unused-result -Wsign-compare >> -DDYNAMIC_ANNOTATIONS_ENABLED=1 -DNDEBUG -O2 -fexceptions -g >> -grecord-gcc-switches -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOU >> 4383 RCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -fstack-protector-strong -m64 >> -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection >> -fcf-protection -D_GNU_SOURCE -fPIC -fwrapv -O >> 4383 2 -fexceptions -g -grecord-gcc-switches -pipe -Wall >> -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS >> -fstack-protector-strong -m64 -mtune=generic -fasyn >> 4383 chronous-unwind-tables -fstack-clash-protection -fcf-protection >> -D_GNU_SOURCE -fPIC -fwrapv -O2 -fexceptions -g -grecord-gcc-switches -pipe >> -Wall -Werror=format-security -Wp,-D_ >> 4383 FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS >> -fstack-protector-strong -m64 -mtune=generic -fasynchronous-unwind-tables >> -fstack-clash-protection -fcf-protection -D_GNU_SOURCE -fPIC >> 4383 -fwrapv -Dlinux -I/usr/include -fPIC >> -I/home/furutaka/work/sage/sage-9.4.rc2-git-clang2/conftest_venv/include >> -I/usr/include/python3.9 -c conftest.cpp -o conftest.dir/temp.linu >> 4383 x-x86_64-3.9/conftest.o -std=c++11 >> 4384 creating conftest.dir/lib.linux-x86_64-3.9 >> 4385 clang++ -pthread -shared -Wl,-z,relro -Wl,--as-needed -Wl,-z,now >> -g -Wl,-z,relro -Wl,--as-needed -Wl,-z,now -g -Dlinux -I/usr/include >> conftest.dir/temp.linux-x86_64-3.9/conftest 4385 .o -L/usr/lib64 -o >> conftest.dir/lib.linux-x86_64-3.9/ >> config_check_distutils_cxx.cpython-39-x86_64-linux-gnu.so >> 4386 configure:34909: result: yes >> 4387 configure:34911: checking for python3 >= 3.7.0, < 3.10.0 with >> modules sqlite3, ctypes, math, hashlib, crypt, socket, zlib, distutils.core >> 4388 configure:34977: result: /usr/bin/python3 >> 4389 configure:34994: will use system package and not install SPKG >> python3 > > > What I did was: > > 1. `git checkout -b <a_tagged_version>` > 2. rsync to a separate directory for building, > 3. `make configure` > 4. `CC=clang CXX=clang++ ./configure` > 5. `./config.status recheck && ./config.status` > 6. `script -c make make.log` > > > By the way I forgot to mention but it's on a linux running fedora-34 > (x86_64). > > Kazuyoshi > -- > Kazuyoshi Furutaka > > -- > You received this message because you are subscribed to the Google Groups > "sage-devel" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sage-devel+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/sage-devel/CANjERveCGS%2Bcqv9yBpDXsAatUw7qBUt3WU4JSqbUEvG2_d%2Bt-A%40mail.gmail.com > <https://groups.google.com/d/msgid/sage-devel/CANjERveCGS%2Bcqv9yBpDXsAatUw7qBUt3WU4JSqbUEvG2_d%2Bt-A%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sage-devel/CA%2B01voMt4--cAM%2BUKSQaVz2GGPMb3w%3D_tfnY-pfdJ4AiNZmzQA%40mail.gmail.com.
