Question

我试图理解为什么使用valgrind后面的代码是错误的。问题显然是在函数destroy_poli中，我说这是因为当我评论这部分主函数时

poli ** p = (poli **) malloc( sizeof( poli *) * npols );
for(k=0;k<npols;k++) {
    p[k] = new_poli( nvars, w  );
}
for(k=0;k<npols;k++)
    destroy_poli(p[k]);
free(p);

我用valgrind得到0错误。请问你能帮我解决我的错误吗？

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "bits.h"
#include "parsemap.h"
#include "galois.h"
#define ANF 1
#define pos(i,j) (((1+i)*i)/2 + j)
int *table_red;
typedef struct _mono {
    int w;
    char ** v;
} mono;

typedef struct _poli {
    int nvars;
    mono ** p;
} poli;

void destroy_mono(mono * m){
    int i=0;
    for(i=0;i<2*(m->w);i++)
        free(m->v[i]);
    free(m->v);

}

void destroy_poli(poli * p){
    int nvars = p->nvars;
    int i;
    for(i=0;i<((nvars+1)*nvars)/2;i++)
        destroy_mono(p->p[i]);
    free(p->p);
}

mono * new_mono( int w, int idx ) {
    int i;
    mono * r = (mono *) malloc( sizeof(mono) );
    r->w = w;
    r->v = (char **) malloc( sizeof(char *)*( 2*w ) );
    for( i = 0; i < 2*w; i++ ) {
        r->v[i] = (char *) malloc( sizeof(char )*( 4096 ) );
        r->v[i][0] = 0;
    }

    return r;
}

poli * new_poli( int nvars, int w  ) {
    poli * p = (poli *) malloc( sizeof(poli) );
    p->nvars = nvars;

    int i,j;
    nvars++;
    p->p = (mono **) malloc( sizeof( mono * ) * ((nvars+1)*nvars)/2);
    nvars--;
    for(i=0; i < nvars; i++ )
    for(j=0; j <=i; j++ )       
            p->p[pos(i,j)] = new_mono( w, i );
    }
   return p;
}

void create_table( int w ) {
    table_red = (int *) malloc( sizeof( int ) * 2 * w );
    int i, j, a, b;
    for(i=0;i<2*w;i++) {
        table_red[i] = mod( (1 << i), w );
    }
}
int ** read_input( int * npols, int * nvars, int * w, int ** enc ) {
    int i, j;
    *npols = 1;
    *nvars = 1;
    int nv = *nvars + 1;
    int np = *npols;
    *enc = (int *) malloc( sizeof( int) * np );
    for(i=0; i < np; i++ ) {
        (*enc)[i] = 0;
    }
    int ** coefs = (int **) malloc( sizeof( int *) * np );
    for(i=0; i < np; i++ ) {
        coefs[i] =  (int *) malloc( sizeof( int) * ((nv+1)*nv)/2 );
        for(j=0; j < ((nv+1)*nv)/2; j++)
        coefs[i][j] = 0;
    }

    return coefs;
}


int main(int argc, char ** argv) {
    int nvars;
    int npols;
    int i;
    int w = 2, *enc;

    int ** coefs = read_input( &npols, &nvars, &w, &enc );
    int k, j;
    create_table( w );
    npols = 1;
    poli ** p = (poli **) malloc( sizeof( poli *) * npols );
    for(k=0;k<npols;k++) {
        p[k] = new_poli( nvars, w  );
    }
    for(k=0;k<npols;k++)
        destroy_poli(p[k]);
    free(p);

    for(i=0; i < npols; i++ )
        free(coefs[i]);
    free(coefs);

    free(enc);
    return 0;
}

==24066== 16 bytes in 1 blocks are definitely lost in loss record 2 of 3
==24066==    at 0x4C2AB80: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==24066==    by 0x400CE8: new_poli (in /home/grados-sanchez/workspace/mq2sat/mq2sat/mq2sat)
==24066==    by 0x400FD7: main (in /home/grados-sanchez/workspace/mq2sat/mq2sat/mq2sat)
==24066== 
==24066== 16 bytes in 1 blocks are definitely lost in loss record 3 of 3
==24066==    at 0x4C2AB80: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==24066==    by 0x400C46: new_mono (in /home/grados-sanchez/workspace/mq2sat/mq2sat/mq2sat)
==24066==    by 0x400D70: new_poli (in /home/grados-sanchez/workspace/mq2sat/mq2sat/mq2sat)
==24066==    by 0x400FD7: main (in /home/grados-sanchez/workspace/mq2sat/mq2sat/mq2sat)
==24066==

Answer 1

free(p)中的destroy_poli()和free(m)中的destroy_mono()遗失了-g。我能够确定通过使用#include <stdio.h> #include <stdlib.h> #include <string.h> #include <math.h> #define ANF 1 #define pos(i, j) (((1 + (i)) * (i)) / 2 + (j)) int *table_red; typedef struct _mono { int w; char **v; } mono; typedef struct _poli { int nvars; mono **p; } poli; void destroy_mono(mono *m) { if (m == NULL) return; for (int i = 0 ; i < 2 * m->w ; i++) free(m->v[i]); free(m->v); free(m); } void destroy_poli(poli *p) { if (p == NULL) return; for (int i = 0 ; i < ((p->nvars + 1) * p->nvars) / 2 ; i++) destroy_mono(p->p[i]); free(p->p); free(p); } mono * new_mono(int w, int idx) { mono *r; r = malloc(sizeof(*r)); if (r == NULL) exit(-1); r->w = w; r->v = malloc(2 * w * sizeof(*r->v)); if (r->v == NULL) exit(-1); for (int i = 0 ; i < 2 * w ; i++) { r->v[i] = malloc(4096); if (r->v[i] == NULL) exit(-1); r->v[i][0] = 0; } return r; } poli * new_poli(int nvars, int w) { poli *p; p = malloc(sizeof(*p)); if (p == NULL) exit(-1); p->nvars = nvars++; p->p = malloc(((nvars + 1) * nvars * sizeof(*p->p)) / 2); if (p->p == NULL) exit(-1); nvars -= 1; for (int i = 0 ; i < nvars ; i++) { for (int j = 0 ; j <= i ; j++) p->p[pos(i, j)] = new_mono(w, i); } return p; } void create_table(int w) { table_red = malloc(2 * w * sizeof(*table_red)); if (table_red == NULL) exit(-1); for (int i = 0 ; i < 2 * w ; i++) table_red[i] = mod((1 << i), w); } int ** read_input(int *npols, int *nvars, int *w, int **enc) { int i, j; int **coefs; int nv; int np; *npols = 1; *nvars = 1; nv = *nvars + 1; np = *npols; enc[0] = malloc(sizeof(**enc) * np); if (enc[0] == NULL) exit(-1); for (i = 0 ; i < np ; i++) enc[0][i] = 0; coefs = malloc(sizeof(*coefs) * np); if (coefs == NULL) exit(-1); for (i = 0 ; i < np ; i++) { coefs[i] = malloc(((nv + 1) * nv) / 2 * sizeof(**coefs)); if (coefs[i] == NULL) exit(-1); for (j = 0 ; j < ((nv + 1) * nv) / 2 ; j++) coefs[i][j] = 0; } return coefs; } int main(int argc, char ** argv) { int nvars; int npols; int i; int w; int *enc; int **coefs; int k; poli **p; w = 2; coefs = read_input(&npols, &nvars, &w, &enc);; create_table(w); npols = 1; p = malloc(npols * sizeof(*p)); for (k = 0 ; k < npols ; k++) { p[k] = new_poli(nvars, w); } for (k = 0 ; k < npols ; k++) destroy_poli(p[k]); free(p); for (i = 0 ; i < npols ; i++) free(coefs[i]); free(coefs); free(enc); return 0; }进行编译并使用 valgrind 来检查分配泄漏指针的行nunmber跟踪它导致我找到问题。我做的另一件事是以可以调试和维护的方式编写代码，请检查并告诉我它是否值得付出努力

finfo

Valgrind Block很丢失

1 个答案: