FORWARD_NULL Vs UNINIT Coverity errors in C
when a pointer is initialized to NULL, getting "FORWARD_NULL" coverity errors and when the NULL initialization is removed, it throws UNINIT coverity errors. The code is as below.
I am very new to coverity. If its a very basic question also, please help.
int fn1(int **ar)
{
int *a = NULL; /* throws forward null. When NULL is removed, coverity throws uninit errors. */
a = *ar;
}
Thanks,
Preethi
c coverity
add a comment |
when a pointer is initialized to NULL, getting "FORWARD_NULL" coverity errors and when the NULL initialization is removed, it throws UNINIT coverity errors. The code is as below.
I am very new to coverity. If its a very basic question also, please help.
int fn1(int **ar)
{
int *a = NULL; /* throws forward null. When NULL is removed, coverity throws uninit errors. */
a = *ar;
}
Thanks,
Preethi
c coverity
1
How exactly does this code makes sense to you? As for why it complains if you drop the NULL, we cannot say without a Minimal, Complete, and Verifiable example. It could also be a tool bug, but none can tell with what's given here.
– Lundin
Nov 13 '18 at 12:04
1
FORWARD_NULL implies that you're dereferencing theNULL
, but that's not what your code shows.
– Sander De Dycker
Nov 13 '18 at 12:21
Your code doesn't match your question. Did you mean*a = **ar
?
– Jabberwocky
Nov 13 '18 at 12:29
Nope. It is matching. @Jabberwocky I wanted to doa = *ar
. But in the lineint *a = NULL
, getting coverity error as mentioned in the comments/* */
– Preethi
Nov 13 '18 at 13:32
add a comment |
when a pointer is initialized to NULL, getting "FORWARD_NULL" coverity errors and when the NULL initialization is removed, it throws UNINIT coverity errors. The code is as below.
I am very new to coverity. If its a very basic question also, please help.
int fn1(int **ar)
{
int *a = NULL; /* throws forward null. When NULL is removed, coverity throws uninit errors. */
a = *ar;
}
Thanks,
Preethi
c coverity
when a pointer is initialized to NULL, getting "FORWARD_NULL" coverity errors and when the NULL initialization is removed, it throws UNINIT coverity errors. The code is as below.
I am very new to coverity. If its a very basic question also, please help.
int fn1(int **ar)
{
int *a = NULL; /* throws forward null. When NULL is removed, coverity throws uninit errors. */
a = *ar;
}
Thanks,
Preethi
c coverity
c coverity
edited Nov 13 '18 at 13:26
Preethi
asked Nov 13 '18 at 11:59
PreethiPreethi
62211
62211
1
How exactly does this code makes sense to you? As for why it complains if you drop the NULL, we cannot say without a Minimal, Complete, and Verifiable example. It could also be a tool bug, but none can tell with what's given here.
– Lundin
Nov 13 '18 at 12:04
1
FORWARD_NULL implies that you're dereferencing theNULL
, but that's not what your code shows.
– Sander De Dycker
Nov 13 '18 at 12:21
Your code doesn't match your question. Did you mean*a = **ar
?
– Jabberwocky
Nov 13 '18 at 12:29
Nope. It is matching. @Jabberwocky I wanted to doa = *ar
. But in the lineint *a = NULL
, getting coverity error as mentioned in the comments/* */
– Preethi
Nov 13 '18 at 13:32
add a comment |
1
How exactly does this code makes sense to you? As for why it complains if you drop the NULL, we cannot say without a Minimal, Complete, and Verifiable example. It could also be a tool bug, but none can tell with what's given here.
– Lundin
Nov 13 '18 at 12:04
1
FORWARD_NULL implies that you're dereferencing theNULL
, but that's not what your code shows.
– Sander De Dycker
Nov 13 '18 at 12:21
Your code doesn't match your question. Did you mean*a = **ar
?
– Jabberwocky
Nov 13 '18 at 12:29
Nope. It is matching. @Jabberwocky I wanted to doa = *ar
. But in the lineint *a = NULL
, getting coverity error as mentioned in the comments/* */
– Preethi
Nov 13 '18 at 13:32
1
1
How exactly does this code makes sense to you? As for why it complains if you drop the NULL, we cannot say without a Minimal, Complete, and Verifiable example. It could also be a tool bug, but none can tell with what's given here.
– Lundin
Nov 13 '18 at 12:04
How exactly does this code makes sense to you? As for why it complains if you drop the NULL, we cannot say without a Minimal, Complete, and Verifiable example. It could also be a tool bug, but none can tell with what's given here.
– Lundin
Nov 13 '18 at 12:04
1
1
FORWARD_NULL implies that you're dereferencing the
NULL
, but that's not what your code shows.– Sander De Dycker
Nov 13 '18 at 12:21
FORWARD_NULL implies that you're dereferencing the
NULL
, but that's not what your code shows.– Sander De Dycker
Nov 13 '18 at 12:21
Your code doesn't match your question. Did you mean
*a = **ar
?– Jabberwocky
Nov 13 '18 at 12:29
Your code doesn't match your question. Did you mean
*a = **ar
?– Jabberwocky
Nov 13 '18 at 12:29
Nope. It is matching. @Jabberwocky I wanted to do
a = *ar
. But in the line int *a = NULL
, getting coverity error as mentioned in the comments /* */
– Preethi
Nov 13 '18 at 13:32
Nope. It is matching. @Jabberwocky I wanted to do
a = *ar
. But in the line int *a = NULL
, getting coverity error as mentioned in the comments /* */
– Preethi
Nov 13 '18 at 13:32
add a comment |
1 Answer
1
active
oldest
votes
In such code:
int fn1(int **ar)
{
int *a;
a = *ar;
}
The variable a
is not initialized (thus UNINIT
) and the variable ar
is dereferenced without checking for null (thus FORWARD_NULL
).
Probably this code will work:
#include <stddef.h>
#include <stdlib.h>
#include <stdio.h>
int fn1(int **ar)
{
int *a = NULL;
if (ar == NULL) {
fprintf(stderr, "Omg! you passed NULL as first argument to fn1 function. What to do now? Break the program flow for sure - return or abort() or exit() !");
abort();
return EXIT_FAILURE;
}
a = *ar;
return EXIT_SUCCESS;
}
Thanks a lot. Trying it out. Once it is going to work, will update this as answer.
– Preethi
Nov 13 '18 at 13:07
I did this:int fn1(int **ar) { int *a = NULL; /* throws forward null, when NULL is removed, coverity throws unint errors. */ if (ar == NULL) { return 1;} a = *ar; }
My coverity error still exists. @kamil
– Preethi
Nov 13 '18 at 13:24
add a comment |
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1 Answer
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1 Answer
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oldest
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oldest
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oldest
votes
In such code:
int fn1(int **ar)
{
int *a;
a = *ar;
}
The variable a
is not initialized (thus UNINIT
) and the variable ar
is dereferenced without checking for null (thus FORWARD_NULL
).
Probably this code will work:
#include <stddef.h>
#include <stdlib.h>
#include <stdio.h>
int fn1(int **ar)
{
int *a = NULL;
if (ar == NULL) {
fprintf(stderr, "Omg! you passed NULL as first argument to fn1 function. What to do now? Break the program flow for sure - return or abort() or exit() !");
abort();
return EXIT_FAILURE;
}
a = *ar;
return EXIT_SUCCESS;
}
Thanks a lot. Trying it out. Once it is going to work, will update this as answer.
– Preethi
Nov 13 '18 at 13:07
I did this:int fn1(int **ar) { int *a = NULL; /* throws forward null, when NULL is removed, coverity throws unint errors. */ if (ar == NULL) { return 1;} a = *ar; }
My coverity error still exists. @kamil
– Preethi
Nov 13 '18 at 13:24
add a comment |
In such code:
int fn1(int **ar)
{
int *a;
a = *ar;
}
The variable a
is not initialized (thus UNINIT
) and the variable ar
is dereferenced without checking for null (thus FORWARD_NULL
).
Probably this code will work:
#include <stddef.h>
#include <stdlib.h>
#include <stdio.h>
int fn1(int **ar)
{
int *a = NULL;
if (ar == NULL) {
fprintf(stderr, "Omg! you passed NULL as first argument to fn1 function. What to do now? Break the program flow for sure - return or abort() or exit() !");
abort();
return EXIT_FAILURE;
}
a = *ar;
return EXIT_SUCCESS;
}
Thanks a lot. Trying it out. Once it is going to work, will update this as answer.
– Preethi
Nov 13 '18 at 13:07
I did this:int fn1(int **ar) { int *a = NULL; /* throws forward null, when NULL is removed, coverity throws unint errors. */ if (ar == NULL) { return 1;} a = *ar; }
My coverity error still exists. @kamil
– Preethi
Nov 13 '18 at 13:24
add a comment |
In such code:
int fn1(int **ar)
{
int *a;
a = *ar;
}
The variable a
is not initialized (thus UNINIT
) and the variable ar
is dereferenced without checking for null (thus FORWARD_NULL
).
Probably this code will work:
#include <stddef.h>
#include <stdlib.h>
#include <stdio.h>
int fn1(int **ar)
{
int *a = NULL;
if (ar == NULL) {
fprintf(stderr, "Omg! you passed NULL as first argument to fn1 function. What to do now? Break the program flow for sure - return or abort() or exit() !");
abort();
return EXIT_FAILURE;
}
a = *ar;
return EXIT_SUCCESS;
}
In such code:
int fn1(int **ar)
{
int *a;
a = *ar;
}
The variable a
is not initialized (thus UNINIT
) and the variable ar
is dereferenced without checking for null (thus FORWARD_NULL
).
Probably this code will work:
#include <stddef.h>
#include <stdlib.h>
#include <stdio.h>
int fn1(int **ar)
{
int *a = NULL;
if (ar == NULL) {
fprintf(stderr, "Omg! you passed NULL as first argument to fn1 function. What to do now? Break the program flow for sure - return or abort() or exit() !");
abort();
return EXIT_FAILURE;
}
a = *ar;
return EXIT_SUCCESS;
}
edited Jan 10 at 16:47
Paul Floyd
2,69811830
2,69811830
answered Nov 13 '18 at 12:23
Kamil CukKamil Cuk
9,9611527
9,9611527
Thanks a lot. Trying it out. Once it is going to work, will update this as answer.
– Preethi
Nov 13 '18 at 13:07
I did this:int fn1(int **ar) { int *a = NULL; /* throws forward null, when NULL is removed, coverity throws unint errors. */ if (ar == NULL) { return 1;} a = *ar; }
My coverity error still exists. @kamil
– Preethi
Nov 13 '18 at 13:24
add a comment |
Thanks a lot. Trying it out. Once it is going to work, will update this as answer.
– Preethi
Nov 13 '18 at 13:07
I did this:int fn1(int **ar) { int *a = NULL; /* throws forward null, when NULL is removed, coverity throws unint errors. */ if (ar == NULL) { return 1;} a = *ar; }
My coverity error still exists. @kamil
– Preethi
Nov 13 '18 at 13:24
Thanks a lot. Trying it out. Once it is going to work, will update this as answer.
– Preethi
Nov 13 '18 at 13:07
Thanks a lot. Trying it out. Once it is going to work, will update this as answer.
– Preethi
Nov 13 '18 at 13:07
I did this:
int fn1(int **ar) { int *a = NULL; /* throws forward null, when NULL is removed, coverity throws unint errors. */ if (ar == NULL) { return 1;} a = *ar; }
My coverity error still exists. @kamil– Preethi
Nov 13 '18 at 13:24
I did this:
int fn1(int **ar) { int *a = NULL; /* throws forward null, when NULL is removed, coverity throws unint errors. */ if (ar == NULL) { return 1;} a = *ar; }
My coverity error still exists. @kamil– Preethi
Nov 13 '18 at 13:24
add a comment |
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1
How exactly does this code makes sense to you? As for why it complains if you drop the NULL, we cannot say without a Minimal, Complete, and Verifiable example. It could also be a tool bug, but none can tell with what's given here.
– Lundin
Nov 13 '18 at 12:04
1
FORWARD_NULL implies that you're dereferencing the
NULL
, but that's not what your code shows.– Sander De Dycker
Nov 13 '18 at 12:21
Your code doesn't match your question. Did you mean
*a = **ar
?– Jabberwocky
Nov 13 '18 at 12:29
Nope. It is matching. @Jabberwocky I wanted to do
a = *ar
. But in the lineint *a = NULL
, getting coverity error as mentioned in the comments/* */
– Preethi
Nov 13 '18 at 13:32