[C malloc/free] ~ free-ing the allocated memory gives c0000005 Windows error

Quote:

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Originally Posted by Spiegel

The question is: is it just the compiler I'm using, or it's an official C rule, that I cant use "_" for "typedef" names?

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No, there is no such rule. However, there are two rules (from C99 Clause 7.1.3 Paragraph 1) that say:

• All identifiers that begin with an underscore and either an uppercase letter or another underscore are always reserved for any use.
• All identifiers that begin with an underscore are always reserved for use as identifiers with file scope in both the ordinary and tag name spaces.

A simple rule of thumb is just to avoid naming things with names that begin with an underscore.

Quote:

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Originally Posted by Spiegel

The name given to this typedef was something like "abc_def" and I was getting an error about something like an "incomplete statement". Banged my head really hard for quite a while, before trying to change the typedef name by taking out the freaking "_". After that, everything worked great.

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The thing is, "something like" is not convincing. For example, compile this program:

Code:

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#include <stdio.h>

typedef struct X {
    double a;
    int b;
} abc_def;

int main(void)
{
    abc_def x = {1.2, 3};
    printf("%f %d\n", x.a, x.b);
    return 0;
}

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What error do you get?

Quote:

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Originally Posted by laserlight

No, there is no such rule. However, there are two rules (from C99 Clause 7.1.3 Paragraph 1) that say:

• All identifiers that begin with an underscore and either an uppercase letter or another underscore are always reserved for any use.
• All identifiers that begin with an underscore are always reserved for use as identifiers with file scope in both the ordinary and tag name spaces.

A simple rule of thumb is just to avoid naming things with names that begin with an underscore.


The thing is, "something like" is not convincing. For example, compile this program:

Code:

---

#include <stdio.h>

typedef struct X {
    double a;
    int b;
} abc_def;

int main(void)
{
    abc_def x = {1.2, 3};
    printf("%f %d\n", x.a, x.b);
    return 0;
}

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What error do you get?

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Tried. And gives no error.

I've also tried to write it my way (noobie way) and it still gives no error. I surrender, I dont know why I got the error before but not now. =p
What I know is that the name had a "_" in the middle and stopped giving the error after I took the "_" off.

Code:

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#include <stdio.h>

typedef struct X { //YOUR WAY
    double a;
    int b;
} abc_def;

int main(void)
{
    abc_def x = {1.2, 3};
    printf("%f %d\n", x.a, x.b);

    struct y_j //MY WAY
    {
        int a;
        int b;
    };

    typedef struct y_j z_w;

    z_w * a;

    return 0;
}

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