> On 14 Dec 2023, at 4:13 AM, 2111191--- via petsc-users
> <[email protected]> wrote:
>
> Dear SLEPc Developers,
>
> I a am student from Tongji University. Recently I am trying to write a c++
> program for matrix solving, which requires importing the PETSc library that
> you have developed. However a lot of errors occur in the cpp file when I use
> #include <petscts.h> directly. I also try to use extern "C" but it gives me
> the error in the picture below. Is there a good way to use the PETSc library
> in a c++ program? (I compiled using cmake and my compiler is g++ (GCC) 4.8.5
> 20150623 (Red Hat 4.8.5-44)).
This compiler (gcc 4.8.5) is known to not be C++11 compliant, but you are using
the -std=c++11 flag.
Furthermore, since version 3.18 (or maybe slightly later), PETSc requires a
C++11-compliant compiler if using C++.
Could you switch to a newer compiler, or try to reconfigure?
Also, you should not put all the include inside an extern { }.
In any case, you’ll need to send the compilation error log and configure.log to
[email protected] <mailto:[email protected]> if you want further
help, as we won’t be able to give a better diagnosis with just the currently
provided information.
Thanks,
Pierre
> My cmakelists.txt is:
>
> cmake_minimum_required(VERSION 3.1.0)
>
> set(CMAKE_INSTALL_RPATH_USE_LINK_PATH TRUE)
>
> set(PETSC $ENV{PETSC_DIR}/$ENV{PETSC_ARCH})
> set(SLEPC $ENV{SLEPC_DIR}/$ENV{PETSC_ARCH})
> set(ENV{PKG_CONFIG_PATH} ${PETSC}/lib/pkgconfig:${SLEPC}/lib/pkgconfig)
>
> set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
> set (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=c99")
>
> project(test)
>
> add_executable(${PROJECT_NAME} eigen_test2.cpp)
> find_package(PkgConfig REQUIRED)
>
> pkg_search_module(PETSc REQUIRED IMPORTED_TARGET PETSc)
> target_link_libraries(${PROJECT_NAME} PkgConfig::PETSc)
>
> The testing code is:eigen_test2.cpp
> extern "C"{
> //#include <petsc.h>
> #include <petscts.h>
> #include <petscdm.h>
> #include <petscdmda.h>
> #include <petscdraw.h>
> }
>
> int main(int argc,char **argv)
> {
> return 0;
> }
>
>
>
> Best regards
>
> Weijie Xu
