From: david.brown@hesbynett.no
On 05/02/2026 00:52, Bart wrote:
> On 04/02/2026 23:39, Keith Thompson wrote:
>> Bart writes:
>> [...]
>>> The problem is that C expects an exact format-code when trying to use
>>> *printf functions, and for that you need to know the exact types of
>>> the expressions being passed. For example:
>>>
>>> uintptr_t x; // from above
examples
>>> double y; //
>>> printf("x * y is %?", x * y); // What's '?'
>>
>> Since you asked...
>>
>> '?' is 'f' (or 'g' or 'e', or 'a', or any of those in upper case).
>> `x * y` is of type double.
>
> The 'from above examples' applies to both x and y. That means that
> 'double' /may/ have been redefined like this (from my post):
>
> #ifdef SQLITE_OMIT_FLOATING_POINT
> # define double sqlite3_int64
> #endif
>
> I don't know what 'sqlite3_int64' is, but it sounds like a signed integer.
>
> I was asked to give examples of conditional types, and thought it best
> to do so from actual programs.
What you have found is an idiocy in SQLITE, not a problem in the C
language or printf. If the macro "SQLITE_OMIT_FLOATING_POINT" is
defined, then the type named "sqlite3_int64" is not an integer type, nor
can it hold arbitrary 64-bit integers (as Michael S pointed out, and I
assume accurately, it can hold 53 bit integers). I do not know what
this type is used for in the code, but something like "sqlite3_bignum"
would be a far better choice of name. And if it is intended that people
print out these values directly, defining "PRsqlite3_bignum" to "%g" or
"%llu" as appropriate would be helpful. (Yes, the resulting printf
statements would be ugly - better ugly and correct than wrong).
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