由于指针类型不兼容而导致编译错误

Question

我一直在尝试编译这个C程序，但它因指针和结构不兼容的一些编译错误而中断。请参阅下面的编译错误。我似乎不知道如何解决这个问题。任何帮助将不胜感激。

build/user/junyan/fft3d_JYAN.c: In function 'fft2d_init':
build/user/junyan/fft3d_JYAN.c:45: warning: assignment from incompatible pointer type
build/user/junyan/fft3d_JYAN.c:46: warning: assignment from incompatible pointer type
build/user/junyan/fft3d_JYAN.c: In function 'fft2d_JYAN':
build/user/junyan/fft3d_JYAN.c:73: error: invalid use of undefined type 'struct kiss_fft_cpx'
build/user/junyan/fft3d_JYAN.c:73: error: dereferencing pointer to incomplete type
build/user/junyan/fft3d_JYAN.c:78: error: invalid use of undefined type 'struct kiss_fft_cpx'
build/user/junyan/fft3d_JYAN.c:78: error: dereferencing pointer to incomplete type
build/user/junyan/fft3d_JYAN.c:94: warning: passing argument 3 of 'kiss_fft_stride' from incompatible pointer type
build/include/rsf.h:152: note: expected 'struct kiss_fft_cpx *' but argument is of type 'struct kiss_fft_cpx *'
build/user/junyan/fft3d_JYAN.c:95: error: invalid use of undefined type 'struct kiss_fft_cpx'
build/user/junyan/fft3d_JYAN.c:95: error: dereferencing pointer to incomplete type
build/user/junyan/fft3d_JYAN.c:103: warning: passing argument 3 of 'kiss_fft_stride' from incompatible pointer type
build/include/rsf.h:152: note: expected 'struct kiss_fft_cpx *' but argument is of type 'struct kiss_fft_cpx *'
build/user/junyan/fft3d_JYAN.c:104: error: invalid use of undefined type 'struct kiss_fft_cpx'
build/user/junyan/fft3d_JYAN.c:104: error: dereferencing pointer to incomplete type
build/user/junyan/fft3d_JYAN.c: In function 'fft3d_init':
build/user/junyan/fft3d_JYAN.c:123: warning: assignment from incompatible pointer type
build/user/junyan/fft3d_JYAN.c:124: warning: assignment from incompatible pointer type
build/user/junyan/fft3d_JYAN.c:125: warning: assignment from incompatible pointer type
build/user/junyan/fft3d_JYAN.c: In function 'fft3d_JYAN':
build/user/junyan/fft3d_JYAN.c:155: error: invalid use of undefined type 'struct kiss_fft_cpx'
build/user/junyan/fft3d_JYAN.c:155: error: dereferencing pointer to incomplete type
build/user/junyan/fft3d_JYAN.c:160: error: invalid use of undefined type 'struct kiss_fft_cpx'
build/user/junyan/fft3d_JYAN.c:160: error: dereferencing pointer to incomplete type
build/user/junyan/fft3d_JYAN.c:165: error: incompatible type for argument 1 of 'sf_crealf'
build/include/rsf.h:1542: note: expected 'kiss_fft_cpx' but argument is of type 'struct kiss_fft_cpx *'
build/user/junyan/fft3d_JYAN.c:166: error: invalid operands to binary / (have 'float *' and 'int')
build/user/junyan/fft3d_JYAN.c:177: warning: passing argument 3 of 'kiss_fft_stride' from incompatible pointer type
build/include/rsf.h:152: note: expected 'struct kiss_fft_cpx *' but argument is of type 'struct kiss_fft_cpx *'
build/user/junyan/fft3d_JYAN.c:178: error: invalid use of undefined type 'struct kiss_fft_cpx'
build/user/junyan/fft3d_JYAN.c:178: error: dereferencing pointer to incomplete type
build/user/junyan/fft3d_JYAN.c:184: error: incompatible type for argument 1 of 'sf_cneg'
build/include/rsf.h:1578: note: expected 'kiss_fft_cpx' but argument is of type 'struct kiss_fft_cpx *'
build/user/junyan/fft3d_JYAN.c:186: warning: passing argument 2 of 'kiss_fft_stride' from incompatible pointer type
build/include/rsf.h:152: note: expected 'const struct kiss_fft_cpx *' but argument is of type 'struct kiss_fft_cpx **'
build/user/junyan/fft3d_JYAN.c:186: warning: passing argument 3 of 'kiss_fft_stride' from incompatible pointer type
build/include/rsf.h:152: note: expected 'struct kiss_fft_cpx *' but argument is of type 'struct kiss_fft_cpx *'
build/user/junyan/fft3d_JYAN.c:187: error: invalid use of undefined type 'struct kiss_fft_cpx'
build/user/junyan/fft3d_JYAN.c:187: error: dereferencing pointer to incomplete type
build/user/junyan/fft3d_JYAN.c:190: error: expected declaration or statement at end of input
build/user/junyan/fft3d_JYAN.c:148: warning: unused variable 'iky'
scons: *** [build/user/junyan/fft3d_JYAN.o] Error 1
scons: building terminated because of errors.
make: *** [all] Error 2

C 程序

/* 3-D  Fourier transform */
/*
  Copyright (C) 2010 University of Texas at Austin

  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/
#include <rsf.h>

static int nkx,nky,nkz;
static kiss_fft_cfg cfgx,cfgxi,cfgy,cfgyi,cfgz,cfgzi;
static kiss_fft_cpx *ctracex,*ctracey,*ctracez;

int fft_nk(int n, int opt)
/*< wavenumber for FT >*/
{
    int nk;

    nk = opt? kiss_fft_next_fast_size(n): n;
    return nk;
}

void fft2d_init(int nz, int nx, int opt)
/*< 2D fft init >*/
{
    nkx = opt? kiss_fft_next_fast_size(nx): nx;
    nkz = opt? kiss_fft_next_fast_size(nz): nz;

    cfgx = kiss_fft_alloc(nkx,0,NULL,NULL);
    cfgxi = kiss_fft_alloc(nkx,1,NULL,NULL);
    cfgz = kiss_fft_alloc(nkz,0,NULL,NULL);
    cfgzi = kiss_fft_alloc(nkz,1,NULL,NULL);

    ctracex = (kiss_fft_cpx *) sf_complexalloc(nkx);
    ctracez = (kiss_fft_cpx *) sf_complexalloc(nkz);
}

void fft2d_close()
/*< 2D fft close >*/
{
    free(ctracex);
    free(ctracez);
    free(cfgx);
    free(cfgxi);
    free(cfgz);
    free(cfgzi);
}

void fft2d_JYAN(bool inv,       /* forward or inverse */ 
        int nz, int nx, /* dimensions */
        kiss_fft_cpx **data,    /* data [nkx][nkz] */
        float **datrl /* if inv==1 * datrl[nx][nz] */)
/*< 2-D transform >*/
{
    int ix, iz, ikx, ikz;

    if (inv) {
        /* Inverse FFT*/
        for (ikz=0; ikz < nkz; ikz++){
         /* Inverse Fourier transform kx to x */
             kiss_fft_stride(cfgxi,(kiss_fft_cpx *)data[0]+ikz,(kiss_fft_cpx *)ctracex,nkz); 
             for (ikx=0; ikx < nkx; ikx++) data[ikx][ikz] = sf_crmul(ctracex[ikx],ikx%2?-1.0:1.0); 
        }
        for (ikx=0; ikx < nkx; ikx++){
         /* Inverse Fourier transform kz to z */
            kiss_fft_stride(cfgzi,(kiss_fft_cpx *)data[ikx],(kiss_fft_cpx *)ctracez,1); 
            for (ikz=0; ikz < nkz; ikz++) data[ikx][ikz] = sf_crmul(ctracez[ikz],ikz%2?-1.0:1.0); 
        }

        for (ix=0; ix < nx; ix++){
            for (iz=0; iz < nz; iz++){ 
                datrl[ix][iz] = sf_crealf(data[ix][iz]); 
                datrl[ix][iz] /= (nkx*nkz); 
            }
        }
    } else {
    /* compute u(kx,kz) */
        for (ix=0; ix < nx; ix++){
            /* Fourier transform z to kz */
            for (iz=1; iz < nz; iz+=2){
                data[ix][iz] = sf_cneg(data[ix][iz]);
            }
            kiss_fft_stride(cfgz,data[ix],ctracez,1); 
            for (ikz=0; ikz<nkz; ikz++) data[ix][ikz] = ctracez[ikz]; 
        }

        for (ikz=0; ikz < nkz; ikz++){
             /* Fourier transform x to kx */
            for (ikx=1; ikx<nkx; ikx+=2){
                data[ikx][ikz] = sf_cneg(data[ikx][ikz]);
            }
            kiss_fft_stride(cfgx,data[0]+ikz,ctracex,nkz); 
            for (ikx=0; ikx<nkx; ikx++) data[ikx][ikz] = ctracex[ikx];
            }
    }
}

void fft3d_init(int nz, int nx, int ny, int opt)
/*< 3D fft init >*/
{
    nkx = opt? kiss_fft_next_fast_size(nx): nx;
    nky = opt? kiss_fft_next_fast_size(ny): ny;
    nkz = opt? kiss_fft_next_fast_size(nz): nz;

    cfgx = kiss_fft_alloc(nkx,0,NULL,NULL);
    cfgxi = kiss_fft_alloc(nkx,1,NULL,NULL);
    cfgy = kiss_fft_alloc(nky,0,NULL,NULL);
    cfgyi = kiss_fft_alloc(nky,1,NULL,NULL);
    cfgz = kiss_fft_alloc(nkz,0,NULL,NULL);
    cfgzi = kiss_fft_alloc(nkz,1,NULL,NULL);

    ctracex = (kiss_fft_cpx *) sf_complexalloc(nkx);
    ctracey = (kiss_fft_cpx *) sf_complexalloc(nky);
    ctracez = (kiss_fft_cpx *) sf_complexalloc(nkz);
}

void fft3d_close()
/*< 3D fft close >*/
{
    free(ctracex);
    free(ctracey);
    free(ctracez);
    free(cfgx);
    free(cfgxi);
    free(cfgy);
    free(cfgyi);
    free(cfgz);
    free(cfgzi);
}

void fft3d_JYAN(bool inv,       /* forward or inverse */ 
        int nz, int nx, int ny,  /* dimensions */
        kiss_fft_cpx ***data,    /* data [nky][nkx][nkz] */
        float ***datrl /* if inv==1 * datrl[ny][nx][nz] */)
/*< 3-D transform >*/
{
    int ix, iy, iz, ikx, iky, ikz;

    if (inv) {
        /* Inverse FFT*/
        for (ikz=0; ikz < nkz; ikz++){
         /* Inverse Fourier transform kx to x */
             kiss_fft_stride(cfgxi,(kiss_fft_cpx *)data[0]+ikz,(kiss_fft_cpx *)ctracex,nkz); 
             for (ikx=0; ikx < nkx; ikx++) data[ikx][ikz] = sf_crmul(ctracex[ikx],ikx%2?-1.0:1.0); 
        }
        for (ikx=0; ikx < nkx; ikx++){
         /* Inverse Fourier transform kz to z */
            kiss_fft_stride(cfgzi,(kiss_fft_cpx *)data[ikx],(kiss_fft_cpx *)ctracez,1); 
            for (ikz=0; ikz < nkz; ikz++) data[ikx][ikz] = sf_crmul(ctracez[ikz],ikz%2?-1.0:1.0); 
        }

        for (ix=0; ix < nx; ix++){
            for (iz=0; iz < nz; iz++){ 
                datrl[ix][iz] = sf_crealf(data[ix][iz]); 
                datrl[ix][iz] /= (nkx*nkz); 
            }
        }
    } else {
    /* compute u(kx,kz) */
        for (iy=0; iy < ny; iy++) {
        for (ix=0; ix < nx; ix++) {
            /* Fourier transform z to kz */
            for (iz=1; iz < nz; iz+=2){
                data[iy][ix][iz] = sf_cneg(data[iy][ix][iz]);
            }
            kiss_fft_stride(cfgz,data[iy][ix],ctracez,1); 
            for (ikz=0; ikz<nkz; ikz++) data[iy][ix][ikz] = ctracez[ikz]; 
        }

        for (ikz=0; ikz < nkz; ikz++){
             /* Fourier transform x to kx */
            for (ikx=1; ikx<nkx; ikx+=2){
                data[ikx][ikz] = sf_cneg(data[ikx][ikz]);
            }
            kiss_fft_stride(cfgx,data[0]+ikz,ctracex,nkz); 
            for (ikx=0; ikx<nkx; ikx++) data[ikx][ikz] = ctracex[ikx];
            }
    }
}

Answer 1

显然，文件 rsf.h 导致这些声明被处理:

struct kiss_fft_cpx;
typedef struct kiss_fft_cpx kiss_fft_cpx;

但它没有声明struct Kiss_fft_cpx的成员。 header 可能存在错误，但如果它附带经过测试的第三方代码，那么更有可能的期望是您提供您自己的struct成员声明。这样的声明将特定于您的特定应用程序(否则没有充分的理由这样做)，但它可能是这样的:

struct kiss_fft_cpx {
    double real;
    double imag;
};

如果这是所需要的，那么文档应该描述执行此操作的要求，以及对struct形式的期望。这样的声明最好在包含 header 之后立即进行。如果您需要在多个文件中使用它，那么您应该将其放入您自己的私有(private) header 中。