我有一个很好的初学者问题,但我现在真的迷路了。我是从PETSc开始的,但是我在编译代码时遇到了问题。我试图使用我自己的Makefile,但是编译器一直在喊“未定义引用”错误。几个小时来,我一直试图自己解决这个问题,但我根本看不出错误。所以,如果你能认识到这个错误,我们将非常感谢你的帮助。
这是整个错误消息:
mpicc petscLUFact.o -L/home/martin/petsc-3.5.2/arch-linux2-c-debug/lib
petscLUFact.o: In function `main':
/home/martin/Dokumenty/Programovani/petscLUFact.c:18: undefined reference to `PetscInitialize'
/home/martin/Dokumenty/Programovani/petscLUFact.c:20: undefined reference to `PETSC_COMM_WORLD'
/home/martin/Dokumenty/Programovani/petscLUFact.c:20: undefined reference to `MatCreate'
/home/martin/Dokumenty/Programovani/petscLUFact.c:21: undefined reference to `MatSetSizes'
/home/martin/Dokumenty/Programovani/petscLUFact.c:22: undefined reference to `MatSetFromOptions'
/home/martin/Dokumenty/Programovani/petscLUFact.c:23: undefined reference to `MatMPIAIJSetPreallocation'
/home/martin/Dokumenty/Programovani/petscLUFact.c:24: undefined reference to `MatGetOwnershipRange'
/home/martin/Dokumenty/Programovani/petscLUFact.c:26: undefined reference to `MatDestroy'
/home/martin/Dokumenty/Programovani/petscLUFact.c:28: undefined reference to `PetscFinalize'
/home/martin/Dokumenty/Programovani/petscLUFact.c:20: undefined reference to `PetscError'
/home/martin/Dokumenty/Programovani/petscLUFact.c:24: undefined reference to `PetscError'
/home/martin/Dokumenty/Programovani/petscLUFact.c:23: undefined reference to `PetscError'
/home/martin/Dokumenty/Programovani/petscLUFact.c:22: undefined reference to `PetscError'
/home/martin/Dokumenty/Programovani/petscLUFact.c:21: undefined reference to `PetscError'
collect2: error: ld returned 1 exit status
make: *** [petscLUFact] Error 1
这是我的.c文件-它还没有完成,只是一个测试:
static char help[] = "Reads a PETSc matrix and vector from a file and reorders it.\n\
-f0 <input_file> : first file to load (small system)\n\
-f1 <input_file> : second file to load (larger system)\n\n";
#include <petscsys.h>
#include <petscmat.h>
int main( int argc, char **args ) {
Mat A; // matice
//IS isrow,iscol; // permutace radku a sloupcu
PetscInt r = 5, c = 5; // rozmery matice
PetscInt i,j; // souradnice v matici
PetscInt Istart, Iend;
PetscInt Ii; // pocitadlo
PetscScalar v; // 2-rozmerne pole ???
PetscErrorCode ierr;
PetscInitialize( &argc, &args, (char*)0, help );
ierr = MatCreate( PETSC_COMM_WORLD, &A );CHKERRQ( ierr );
ierr = MatSetSizes( A, PETSC_DECIDE, PETSC_DECIDE, r*c, r*c );CHKERRQ(ierr);
ierr = MatSetFromOptions(A);CHKERRQ(ierr);
ierr = MatMPIAIJSetPreallocation( A, 5, PETSC_NULL, 5, PETSC_NULL );CHKERRQ(ierr);
ierr = MatGetOwnershipRange(A,&Istart,&Iend);CHKERRQ(ierr);
MatDestroy(&A);
PetscFinalize();
return 0;
}
这是我的Makefile:
include ${PETSC_DIR}/conf/variables
include ${PETSC_DIR}/conf/rules
CFLAGS=-I${PETSC_DIR}/include -I${PETSC_DIR}/${PETSC_ARCH}/include
petscLUFact: petscLUFact.o
mpicc petscLUFact.o -L${LD_LIBRARY_PATH}
petscLUFact.o: petscLUFact.c
mpicc ${CFLAGS} -c petscLUFact.c -o petscLUFact.o
在
$PETSC_DIR/include
和${PETSC_DIR}/${PETSC_ARCH}/include
中,找到了petsc头(.h)文件。我的系统变量值是:
$PETSC_DIR=/home/martin/petsc-3.5.2
$PETSC_ARCH=arch-linux2-c-debug
$LD_LIBRARY_PATH=/home/martin/petsc-3.5.2/arch-linux2-c-debug/lib
这是我的LD_LIBRARY_PATH文件夹的结构:
arch-linux2-c-debug/lib
├── libpetsc.a
├── libpetsc.so -> libpetsc.so.3.5.2
├── libpetsc.so.3.5 -> libpetsc.so.3.5.2
├── libpetsc.so.3.5.2
├── modules
│ └── 3.5.2-arch-linux2-c-debug
└── pkgconfig
└── PETSc.pc
最佳答案
(在评论和编辑中回答。见Question with no answers, but issue solved in the comments (or extended in chat))
@卫斯理·布兰德写道:
您实际在哪里将库传递给链接器(或者在本例中是mpicc
命令)?看起来除了-lpetsc
标志之外,您还需要一个-L<stuff>
标志。
评论写道:
我在-lpetsc
中添加了一个Makefile
标志,所以现在看起来像这样:
include ${PETSC_DIR}/conf/variables
include ${PETSC_DIR}/conf/rules
CFLAGS=-I${PETSC_DIR}/include -I${PETSC_DIR}/${PETSC_ARCH}/include
petscLUFact: petscLUFact.o
mpicc petscLUFact.o -o petscLUFact -L${LD_LIBRARY_PATH} -lpetsc
petscLUFact.o: petscLUFact.c
mpicc ${CFLAGS} -c petscLUFact.c -o petscLUFact.o
关于c - PETSc未定义引用,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/26485666/