值存儲在C結構「神奇」以下類型的自己

Question

我有一個結構（具有嵌套）變化：

typedef struct { 
    float precursor_mz; 
    float precursor_int; 
    int scan; 
    float time; 
    spectrum* spectra; /* Nested struct */ 
    int array_length; 
    int mz_length; 
    int int_length; 
    char* mz_binary; 
    char* int_binary; 
    int hits; 
} compound; 
typedef struct { 
    float mz_value; 
    float int_value; 
    int peaks; 
} spectrum; 

我改變這個結構，允許我使用的qsort，後我將它存儲爲我自己的'類型'。幾行後面的代碼我希望循環結構，但不知何故值更改沒有我訪問他們（之間）。代碼片斷如下：

// The transformating & qsort chunk 
    for (i = 0; i < compounds->hits; i++) { 
     spectrum test[(compounds+i)->spectra->peaks]; 
     for (j = 0; j < (compounds+i)->spectra->peaks; j++) { 
      test[j] = *((compounds+i)->spectra+j); 
     } 
     qsort(test,(compounds+i)->spectra->peaks,sizeof(spectrum),compare_mz); 
     for (j = 0; j < (compounds+i)->spectra->peaks; j++) { 
      ((compounds+i)->spectra+j)->mz_value = test[j].mz_value; 
      ((compounds+i)->spectra+j)->int_value = test[j].int_value; 
      if (j < 10) { 
       printf("%i %i\t", i, j); 
       printf("%f %f\n",((compounds+i)->spectra+j)->mz_value, ((compounds+i)->spectra+j)->int_value); // Here values are still correct 
      } 
     } 
    } 


/* Summing values that are in 'mass-tolerance' of each other */ 
    float int_total; 
    float mz_int_total; 
    for (i = 0; i < compounds->hits; i++) { 
     counter = 0; 
     printf("---\n"); 
     for (j = 0; j < (compounds+i)->spectra->peaks; j++) { 
      lower_mass = ((compounds+i)->spectra+j)->mz_value - 0.05; //args->mass_tolerance; 
      upper_mass = ((compounds+i)->spectra+j)->mz_value + 0.05; //args->mass_tolerance; 
      if (j < 10) { 
       printf("%i %i\t", i , j); 
       printf("%f %f\n",((compounds+i)->spectra+j)->mz_value, ((compounds+i)->spectra+j)->int_value); // Here values are borked 
      } 
      // Rest of the code chopped off as it should be irrelevant 

但此代碼產生以下輸出：

tarskin@5-PARA-11-0120:/data/programming/C/Compound_Spectra$ ./Run -f ../PeptMoiety/32757_p_01.mzML -c 1 
0 0 168.858765 32489.994141 
0 1 168.960327 72930.046875 
0 2 169.039993 4924.188477 
0 3 169.913681 85340.171875 
0 4 169.932312 2406.798096 
0 5 171.000320 345949.593750 
0 6 171.007950 1034718.312500 
0 7 171.034088 882886.562500 
0 8 171.034378 58554.589844 
0 9 171.056320 871035.500000 
--- 
0 0 168.858765 32489.994141 
0 1 168.960327 72930.046875 
0 2 169.039993 4924.188477 
0 3 169.913681 85340.171875 
0 4 0.000000 0.000000 
0 5 169.932312 2406.798096 
0 6 171.007950 1034718.312500 
0 7 0.000000 0.000000 
0 8 0.000000 0.000000 
0 9 0.000000 0.000000 

沒有人有任何想法可能是什麼回事？

- EDIT 1 -

ALK請求compare_mz的代碼，其中如下：

int 
compare_mz (const void *a, const void *b) 
{ 
    const spectrum *fa = (const spectrum *) a; 
    const spectrum *fb = (const spectrum *) b; 

    return (fa->mz_value > fb->mz_value) 
      -(fa->mz_value < fb->mz_value); 
} 

測試用例，我表明是爲單一化合物（所以我= 1）。

Answer 1

我強烈地認爲spectrum* spectra; /* Nested struct */引用的內存沒有被正確地分配或者被部分釋放。

嘗試使用valgrind運行您的應用。

而且（如果你使用的是gcc）：你如果使用gcc的-Wall和/或-pedantic選項得到任何編譯警告？

---

試試下面的MOD /，看看應用程序/表現不同（堆棧將不間觸及到for (j=0;..;..)循環這樣）：

float int_total; 
float mz_int_total; 
spectrum test[(compounds+i)->spectra->peaks]; 

for (i = 0; i < compounds->hits; i++) { 
    ... 

/* Summing values that are in 'mass-tolerance' of each other */  
for (i = 0; i < compounds->hits; i++) { 
    ...