Обсуждение: [PATCH] Fix wrong argument to SOFT_ERROR_OCCURRED in timestamptz_date

On Tue, Mar 24, 2026 at 08:44:29AM -0700, Jianghua Yang wrote:
>   I found a small bug in commit e2f289e5b9b ("Make many cast functions
> error safe").

Nice find.  For future reference, since this was just committed, it
might've been better to report it directly in the thread where the change
was discussed.

>   The fix is a one-line change: fcinfo->args → fcinfo->context.

LGTM.  To prevent this from happening in the future, I think we ought to
change SOFT_ERROR_OCCURRED to a static inline function.  I tried that, and
I got the following warnings:

    execExprInterp.c:4964:27: warning: incompatible pointer types passing 'ErrorSaveContext *' (aka 'struct
ErrorSaveContext*') to parameter of type 'Node *' (aka 'struct Node *') [-Wincompatible-pointer-types]
 
     4964 |                 if (SOFT_ERROR_OCCURRED(&jsestate->escontext))
          |                                         ^~~~~~~~~~~~~~~~~~~~
    ../../../src/include/nodes/miscnodes.h:54:27: note: passing argument to parameter 'escontext' here
       54 | SOFT_ERROR_OCCURRED(Node *escontext)
          |                           ^
    execExprInterp.c:5200:26: warning: incompatible pointer types passing 'ErrorSaveContext *' (aka 'struct
ErrorSaveContext*') to parameter of type 'Node *' (aka 'struct Node *') [-Wincompatible-pointer-types]
 
     5200 |         if (SOFT_ERROR_OCCURRED(&jsestate->escontext))
          |                                 ^~~~~~~~~~~~~~~~~~~~
    ../../../src/include/nodes/miscnodes.h:54:27: note: passing argument to parameter 'escontext' here
       54 | SOFT_ERROR_OCCURRED(Node *escontext)
          |                           ^

I think we just need to add casts to "Node *" for those.  AFAICT there
isn't an actual bug.

[... looks for past discussions ...]

Ah, I noticed this thread, where the same lines of code were discussed:

    https://postgr.es/m/flat/20240724.155525.366150353176322967.ishii%40postgresql.org

-- 
nathan

On 24.03.26 16:44, Jianghua Yang wrote:
>   Hi hackers,
> 
>    I found a small bug in commit e2f289e5b9b ("Make many cast functions 
> error safe").
> 
>    In timestamptz_date(), the SOFT_ERROR_OCCURRED() check mistakenly
>    uses fcinfo->args instead of fcinfo->context:
> 
>    result = timestamptz2date_safe(timestamp, fcinfo->context);
>    if (SOFT_ERROR_OCCURRED(fcinfo->args))   /* should be fcinfo->context */
>        PG_RETURN_NULL();
> 
>    fcinfo->args is a NullableDatum[] array, not a Node *. The
>    SOFT_ERROR_OCCURRED macro casts its argument to Node * and reads
>    the NodeTag field. When given fcinfo->args, it interprets the first
>    argument's Datum value (a TimestampTz) as a NodeTag, which will
>    almost never match T_ErrorSaveContext. This causes the soft error
>    check to always evaluate to false.
> 
>    As a result, when the timestamptz-to-date conversion encounters an
>    overflow in error-safe mode, the function returns a wrong date value
>    instead of the expected NULL.
> 
>    All three sibling functions modified in the same commit (date_timestamp,
>    timestamp_date, date_timestamptz) correctly use fcinfo->context.
>    This appears to be a copy-paste oversight.
> 
>    The fix is a one-line change: fcinfo->args → fcinfo->context.

committed the fix, thanks

On 24.03.26 21:53, Nathan Bossart wrote:
> LGTM.  To prevent this from happening in the future, I think we ought to
> change SOFT_ERROR_OCCURRED to a static inline function.  I tried that, and
> I got the following warnings:
> 
>      execExprInterp.c:4964:27: warning: incompatible pointer types passing 'ErrorSaveContext *' (aka 'struct
ErrorSaveContext*') to parameter of type 'Node *' (aka 'struct Node *') [-Wincompatible-pointer-types]
 
>       4964 |                 if (SOFT_ERROR_OCCURRED(&jsestate->escontext))
>            |                                         ^~~~~~~~~~~~~~~~~~~~
>      ../../../src/include/nodes/miscnodes.h:54:27: note: passing argument to parameter 'escontext' here
>         54 | SOFT_ERROR_OCCURRED(Node *escontext)
>            |                           ^
>      execExprInterp.c:5200:26: warning: incompatible pointer types passing 'ErrorSaveContext *' (aka 'struct
ErrorSaveContext*') to parameter of type 'Node *' (aka 'struct Node *') [-Wincompatible-pointer-types]
 
>       5200 |         if (SOFT_ERROR_OCCURRED(&jsestate->escontext))
>            |                                 ^~~~~~~~~~~~~~~~~~~~
>      ../../../src/include/nodes/miscnodes.h:54:27: note: passing argument to parameter 'escontext' here
>         54 | SOFT_ERROR_OCCURRED(Node *escontext)
>            |                           ^
> 
> I think we just need to add casts to "Node *" for those.  AFAICT there
> isn't an actual bug.

Or maybe we change the escontext field to be of type Node *?

On Wed, Mar 25, 2026 at 07:17:15AM +0100, Peter Eisentraut wrote:
> On 24.03.26 21:53, Nathan Bossart wrote:
>> LGTM.  To prevent this from happening in the future, I think we ought to
>> change SOFT_ERROR_OCCURRED to a static inline function.  I tried that, and
>> I got the following warnings:
>> 
>>      execExprInterp.c:4964:27: warning: incompatible pointer types passing 'ErrorSaveContext *' (aka 'struct
ErrorSaveContext*') to parameter of type 'Node *' (aka 'struct Node *') [-Wincompatible-pointer-types]
 
>>       4964 |                 if (SOFT_ERROR_OCCURRED(&jsestate->escontext))
>>            |                                         ^~~~~~~~~~~~~~~~~~~~
>>      ../../../src/include/nodes/miscnodes.h:54:27: note: passing argument to parameter 'escontext' here
>>         54 | SOFT_ERROR_OCCURRED(Node *escontext)
>>            |                           ^
>>      execExprInterp.c:5200:26: warning: incompatible pointer types passing 'ErrorSaveContext *' (aka 'struct
ErrorSaveContext*') to parameter of type 'Node *' (aka 'struct Node *') [-Wincompatible-pointer-types]
 
>>       5200 |         if (SOFT_ERROR_OCCURRED(&jsestate->escontext))
>>            |                                 ^~~~~~~~~~~~~~~~~~~~
>>      ../../../src/include/nodes/miscnodes.h:54:27: note: passing argument to parameter 'escontext' here
>>         54 | SOFT_ERROR_OCCURRED(Node *escontext)
>>            |                           ^
>> 
>> I think we just need to add casts to "Node *" for those.  AFAICT there
>> isn't an actual bug.
> 
> Or maybe we change the escontext field to be of type Node *?

I started looking at this, but it seems to be a rather invasive change for
the level of gain.  Not only does it require more memory management, but we
then have to cast it many places like this:

    ((ErrorSaveContext *) jsestate->escontext)->error_occured = false;

If we instead make it an ErrorSaveContext *, we'd still need to cast it to
Node * for SOFT_ERROR_OCCURRED, unless we had it accept a void * or
something, which defeats the purpose.

-- 
nathan