Question

I have this code

 struct PDATA{
    int NTH;
    int NPH;
    double th_start;
    double th_step;
    double ph_start;
    double ph_step;
    };

    typedef struct PDATA *PDATA_P;

    struct PDATA PAT_DATA;
    PDATA_P PAT_DATA_P;

    PAT_DATA_P = (PDATA_P) malloc(sizeof(struct PDATA));
    PAT_DATA_P=&PAT_DATA;

    ....

    free(PAT_DATA_P); 

When i free my pointer i obtain this error:

*** glibc detected *** /home/pc-linux/Desktop/Projects/AM_v0.1/Debug/AM_v0.1: free(): invalid pointer: 0xbfffe03c ***

Where the error is?

Answer 1

You assign the address of a variable allocated in stack to your pointer with the following line:

PAT_DATA_P=&PAT_DATA;

Then you try to free it!