[Bug c++/124469] New: error: 'format' attribute argument 3 value '6' does not refer to a variable argument list

[office at faf dot software via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124469

            Bug ID: 124469
           Summary: error: 'format' attribute argument 3 value '6' does
                    not refer to a variable argument list
           Product: gcc
           Version: 15.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: office at faf dot software
  Target Milestone: ---

The below code doesn't compile - the error message is in the "Summary".
The parameter 6 is a variable argument list - "this" is 1st, therefore the
counting starts from 2.
Commenting the line with "__attribute__..." compiles and produces the output.
gcc would complain regarding "%d" because I provide an unsigned integer.

https://godbolt.org/z/EqhT5xare

#include <vector>
#include <source_location>
#include <stdio.h>
typedef unsigned int uint;

constexpr std::size_t MAX_LOG_LINE_LENGTH = { 2'500 };

enum LogControllerMode
//--------------------
{
    Default = 0,
};

enum class LogControllerType
//--------------------------
{
    Normal,
};

template <typename... Ts>
//-----------------------
struct FAEWE_LOG
{
    __attribute__ ((format(printf, 5, 7)))
        FAEWE_LOG( const uint instrumentsId,
               [[maybe_unused]] const LogControllerMode logMode,
               [[maybe_unused]] const std::vector<LogControllerType> &
logControllerType,
               const char * formatString, Ts &&... LogArguments,
               const std::source_location & sourceLocation =
std::source_location::current() )
        {
            char resolvedParameters [MAX_LOG_LINE_LENGTH];
            snprintf( resolvedParameters, sizeof(resolvedParameters),
formatString, LogArguments...);
            printf( "%s:%d - [%d] %s\n", sourceLocation.file_name(),
sourceLocation.line(),
            instrumentsId, resolvedParameters );
        }

};

template <typename... Ts>
FAEWE_LOG( const uint, const LogControllerMode, const
std::vector<LogControllerType>, const char *, Ts &&... )
    -> FAEWE_LOG<Ts...>;

auto main () -> int
{
    FAEWE_LOG( 5, LogControllerMode::Default, { LogControllerType::Normal },
    " This is not a correct printf %s string %d", "formatted", 73U );
    return 0;
}