Ok - I see this issue on CentOS [Stream/9]. What I have is: >>> [balay@frog petsc]$ clang --version clang version 19.1.7 (CentOS 19.1.7-1.el9) Target: x86_64-redhat-linux-gnu Thread model: posix InstalledDir: /usr/bin Configuration file: /etc/clang/x86_64-redhat-linux-gnu-clang.cfg [balay@frog petsc]$ gfortran --version GNU Fortran (GCC) 11.5.0 20240719 (Red Hat 11.5.0-5) Copyright (C) 2021 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. <<<<
Now I build: >>> [balay@frog petsc]$ ./configure --with-cc=clang --with-cxx=clang++ --with-fc=gfortran --with-mpi=0 && make && make check <snip> ********************************************************************************* clang -fPIC -Wall -Wwrite-strings -Wno-unknown-pragmas -Wconversion -Wno-sign-conversion -Wno-float-conversion -Wno-implicit-float-conversion -fstack-protector -Qunused-arguments -fvisibility=hidden -Wall -Wwrite-strings -Wno-unknown-pragmas -Wconversion -Wno-sign-conversion -Wno-float-conversion -Wno-implicit-float-conversion -fstack-protector -Qunused-arguments -fvisibility=hidden -g3 -O0 -I/home/balay/petsc/include -I/home/balay/petsc/arch-linux-c-debug/include -Wl,-export-dynamic ex19.c -Wl,-rpath,/home/balay/petsc/arch-linux-c-debug/lib -L/home/balay/petsc/arch-linux-c-debug/lib -Wl,-rpath,/usr/lib/gcc/x86_64-redhat-linux/11 -L/usr/lib/gcc/x86_64-redhat-linux/11 -lpetsc -llapack -lblas -lm -lX11 -lgfortran -lm -lgfortran -lm -lgcc_s -lquadmath -lstdc++ -o ex19 /opt/rh/gcc-toolset-14/root//usr/lib/gcc/x86_64-redhat-linux/14/../../../../bin/ld: /home/balay/petsc/arch-linux-c-debug/lib/libpetsc.so: undefined reference to `std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_replace_cold(char*, unsigned long, char const*, unsigned long, unsigned long)' <snip> <<<< Ok some v11 compiler libraries are getting mixed up (likely from -lgfortran) causing grief. >>>>>>>> [root@frog ~]# yum remove gcc-toolset-14-runtime Dependencies resolved. ================================================================================ Package Arch Version Repository Size ================================================================================ Removing: gcc-toolset-14-runtime x86_64 14.0-1.el9 @appstream 11 k Removing dependent packages: clang x86_64 19.1.7-1.el9 @appstream 181 k clang-tools-extra x86_64 19.1.7-1.el9 @appstream 69 M gcc-toolset-14-binutils x86_64 2.41-3.el9 @appstream 27 M Removing unused dependencies: clang-libs x86_64 19.1.7-1.el9 @appstream 413 M clang-resource-filesystem x86_64 19.1.7-1.el9 @appstream 15 k compiler-rt x86_64 19.1.7-1.el9 @appstream 37 M gcc-toolset-14-gcc x86_64 14.2.1-7.1.el9 @appstream 122 M gcc-toolset-14-gcc-c++ x86_64 14.2.1-7.1.el9 @appstream 39 M gcc-toolset-14-libstdc++-devel x86_64 14.2.1-7.1.el9 @appstream 22 M libomp x86_64 19.1.7-1.el9 @appstream 1.9 M libomp-devel x86_64 19.1.7-1.el9 @appstream 31 M Transaction Summary ================================================================================ Remove 12 Packages Freed space: 763 M Is this ok [y/N]: <<<<< So this install of clang depends-on/requires gcc-toolset-14-gcc. Also gfortran-14 is missing. Try installing it. >>>> [root@frog ~]# yum install gcc-toolset-14-gcc-gfortran <<<< Now retry build: >>> [balay@frog petsc]$ ./configure --with-cc=clang --with-cxx=clang++ --with-fc=gfortran --with-mpi=0 && make && make check <snip> Running PETSc check examples to verify correct installation Using PETSC_DIR=/home/balay/petsc and PETSC_ARCH=arch-linux-c-debug C/C++ example src/snes/tutorials/ex19 run successfully with 1 MPI process Fortran example src/snes/tutorials/ex5f run successfully with 1 MPI process Completed PETSc check examples [balay@frog petsc]$ <<<< Hm - Using gfortran-11 here [with gfortran-14 installed] somehow worked! But perhaps its better to use gfortran-14 [as this install of clang requires g++-14] >>>> [balay@frog petsc]$ export PATH=/opt/rh/gcc-toolset-14/root/usr/bin:$PATH [balay@frog petsc]$ gfortran --version GNU Fortran (GCC) 14.2.1 20250110 (Red Hat 14.2.1-7) Copyright (C) 2024 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. [balay@frog petsc]$ ./configure --with-cc=clang --with-cxx=clang++ --with-fc=gfortran --with-mpi=0 && make && make check <snip> CLINKER arch-linux-c-debug/lib/libpetsc.so.3.22.3 ========================================= Now to check if the libraries are working do: make PETSC_DIR=/home/balay/petsc PETSC_ARCH=arch-linux-c-debug check ========================================= Running PETSc check examples to verify correct installation Using PETSC_DIR=/home/balay/petsc and PETSC_ARCH=arch-linux-c-debug C/C++ example src/snes/tutorials/ex19 run successfully with 1 MPI process Fortran example src/snes/tutorials/ex5f run successfully with 1 MPI process Completed PETSc check examples [balay@frog petsc]$ <<<< So that worked! Satish On Thu, 20 Feb 2025, Satish Balay wrote: > Actually, simpler: > > ./configure --with-cc=clang --with-cxx=clang++ --with-fc=gfortran > --with-mpi=0 > --download-fblaslapack="$(DIR_SRC)/fblaslapack-$(FBLASLAPACK_VERSION).tar.gz" > && make && make check > > > /opt/rh/gcc-toolset-12/root/usr/lib/gcc/x86_64-redhat-linux/12/../../../../bin/ld > > Hm - there was in issue with some (clang versions?) incompatibilities with > gcc-12 - I think using gcc-11 (system default in that use case) worked. I'm > not sure if you are seeing the same issue here. > > Satish > > On Thu, 20 Feb 2025, Satish Balay wrote: > > > > > Any particular reason to use these flags? What clang version? OS? > > > > Best if you can send build logs [perhaps to petsc-maint] > > > > Can you try a simpler build and see if it works: > > > > ./configure --with-mpi-dir=/PATH_TO/models/src/v2021.03-2.0.3-llvm > > --download-fblaslapack="$(DIR_SRC)/fblaslapack-$(FBLASLAPACK_VERSION).tar.gz" > > && make && make check > > or: > > ./configure --with-cc=clang --with-cxx=clang++ --with-fc=gfortran > > --download-mpich="$(DIR_SRC)/mpich-$(MPICH_VERSION).tar.gz" > > --download-fblaslapack="$(DIR_SRC)/fblaslapack-$(FBLASLAPACK_VERSION).tar.gz" > > && make && make check > > > > Satish > > > > On Thu, 20 Feb 2025, Michael Schaferkotter wrote: > > > > > build petsc-3.20.3 with llvm, clang, clang++, gfortran > > > > > > CFLAGS='-std=c++11' > > > CXXFLAGS='-std=c++11 -D_GLIBCXX_USE_CXX11_ABI=1' > > > LDLIBS += -lstdc++ > > > > > > $PETSC_ARCH arch-linux-c-opt > > > MPIF90 = ./models/src/v2021.03-2.0.3-llvm/bin/mpif90 > > > MPICC = ./models/src/v2021.03-2.0.3-llvm/bin/mpicc > > > CLANG = clang > > > FC = gfortran > > > > > > > > > Petsc libraries are built; > > > /models/src/v2021.03-2.0.3-llvm/lib/libpetsc.so@ > > > /models/src/v2021.03-2.0.3-llvm/lib/libpetsc.so.3.020@ > > > /models/src/v2021.03-2.0.3-llvm/lib/libpetsc.so.3.020.3* > > > > > > > > > The configure is this: > > > cd $(PETSC_SRC) && unset CXX CC FC F77 && $(PYTHON2) ./configure > > > --prefix=$(PREFIX) \ > > > --with-cc=clang \ > > > --with-cxx=clang++ \ > > > --with-fc=gfortran \ > > > --download-mpich="$(DIR_SRC)/mpich-$(MPICH_VERSION).tar.gz" \ > > > > > > --download-fblaslapack="$(DIR_SRC)/fblaslapack-$(FBLASLAPACK_VERSION).tar.gz" > > > \ > > > --download-sowing \ > > > --with-debugging=$(PETSC_DBG) \ > > > --with-shared-libraries=1 \ > > > CFLAGS='-std=c11' \ > > > CXXFLAGS='-std=c++11 -D_GLIBCXX_USE_CXX11_ABI=1' \ > > > CPPFLAGS='-D_GLIBCXX_USE_CXX11_ABI=1' \ > > > LDFLAGS='-L$(LLVM_LIB)' \ > > > LIBS='-lstdc++’ \ > > > --COPTFLAGS=$(COPTFLAGS) --CXXOPTFLAGS=$(CXXOPTFLAGS) > > > --FOPTFLAGS=$(FOPTFLAGS) > > > > > > > > > Here is the make: > > > > > > $(MAKE) -C $(PETSC_SRC) PETSC_DIR=$(PETSC_SRC) > > > PETSC_ARCH=$(PETSC_ARCH) all > > > > > > > > > Check-petsc is: > > > > > > $(MAKE) -C $(PETSC_SRC) PETSC_DIR=$(PETSC_SRC) > > > PETSC_ARCH=$(PETSC_ARCH) test > > > > > > Here is the log file for test: > > > > > > make[1]: Entering directory > > > '/models/src/v2021.03-2.0.3-llvm/build/petsc/petsc-3.20.3' > > > /usr/bin/python3 > > > /models/src/v2021.03-2.0.3-llvm/build/petsc/petsc-3.20.3/config/gmakegentest.py > > > --petsc-dir=/models/src/v2021.03-2.0.3-llvm/build/petsc/petsc-3.20.3 > > > --petsc-arch=arch-linux-c-opt --testdir=./arch-linux-c-opt/tests --srcdir > > > /models/src/v2021.03-2.0.3-llvm/build/petsc/petsc-3.20.3/src --pkg-pkgs > > > "sys vec mat dm ksp snes ts tao" > > > Using MAKEFLAGS: iw -- PETSC_ARCH=arch-linux-c-opt > > > PETSC_DIR=/models/src/v2021.03-2.0.3-llvm/build/petsc/petsc-3.20.3 > > > CC arch-linux-c-opt/tests/sys/classes/draw/tests/ex1.o > > > CLINKER arch-linux-c-opt/tests/sys/classes/draw/tests/ex1 > > > /opt/rh/gcc-toolset-12/root/usr/lib/gcc/x86_64-redhat-linux/12/../../../../bin/ld: > > > arch-linux-c-opt/lib/libpetsc.so: undefined reference to > > > `std::__cxx11::basic_ostringstream<char, std::char_traits<char>, > > > std::allocator<char> >::basic_ostringstream()' > > > /opt/rh/gcc-toolset-12/root/usr/lib/gcc/x86_64-redhat-linux/12/../../../../bin/ld: > > > arch-linux-c-opt/lib/libpetsc.so: undefined reference to > > > `std::__throw_bad_array_new_length()' > > > clang: error: linker command failed with exit code 1 (use -v to see > > > invocation) > > > make[1]: [gmakefile.test:273: > > > arch-linux-c-opt/tests/sys/classes/draw/tests/ex1] Error 1 (ignored) > > > > > > > > > There are many errors of the ilk: > > > > > > std::__cxx11::basic_ostringstream<char, std::char_traits<char>, > > > std::allocator<char> >::basic_ostringstream() > > > > > > [lib]$ nm -A libpetsc.so | grep basic_ostringstream > > > libpetsc.so: U > > > _ZNKSt7__cxx1119basic_ostringstreamIcSt11char_traitsIcESaIcEE3strEv@GLIBCXX_3.4.21 > > > libpetsc.so: U > > > _ZNSt7__cxx1119basic_ostringstreamIcSt11char_traitsIcESaIcEEC1Ev > > > libpetsc.so: U > > > _ZNSt7__cxx1119basic_ostringstreamIcSt11char_traitsIcESaIcEED1Ev@GLIBCXX_3.4.21 > > > > > > > > > I/m new to llvm and this is the first time to compile petsc.3.20.3 with > > > llvm compilers. > > > > > > Clearly something is amiss. > > > > > > Any ideas appreciated. > > > > > > Michael > > > > > > > > > > > >