More C type errors by default for GCC 14

[Eli Schwartz]

On 5/14/23 1:28 AM, Po Lu wrote:
>> You may feel free to take an exact GCC release (source or binary),
>> analyze it, reverse-engineer it, or verify that it does what you want
>> it to do, and then trust that those undefined and undocumented
>> behaviors are ***benevolent***, but that doesn't cause it to be
>> defined and documented, and your trust will, if you are wise, depend
>> on you pinning an exact source code commit of the compiler. Do not
>> depend on bugfix releases of GCC to preserve your undocumented
>> semantics. They may or they may not, but if they don't, it's not a GCC
>> bug, because it is ***undocumented***.
> 
> GCC does not implement its documentation.  The documentation is supposed
> to describe (_not_ specify) how GCC behaves, and when the documentation
> is wrong or contains omissions, the documentation will have to be fixed.
> Not the compiler itself.
> 
> And it's not just GCC.  Almost all programs work this way.


But perhaps we can solve this argument.

Please submit a bug report at https://gcc.gnu.org/bugzilla/ to report
that the documentation is wrong or contains omissions, and has to be fixed.

Point out that the C Extensions page omits the documentation on implicit
function declarations and implicit ints. Consider including a patch that
updates https://gcc.gnu.org/onlinedocs/gcc/C-Extensions.html to mention
them as well.

If and when this page is updated to document that the compiler's
behavior with these features constitutes a C Extension, then I will
withdraw every comment I have made in this thread.


-- 
Eli Schwartz