Re: fpending Android bug

[Po Lu]

Bruno Haible <bruno@clisp.org> writes:

> Before we make any change, we need to know what is wrong, i.e. what is
> "the fpending bug on Android". You haven't said so, after I asked in
>  <https://lists.gnu.org/archive/html/bug-gnulib/2022-12/msg00087.html>
>
> Please be specific: What do you mean by "not works"? Does not compile?
> Does not return which value?

Apologies for missing those details.

It doesn't compile because ->_p and ->_base are undefined in FILE *.

>> diff --git a/xcompile/lib/fpending.c b/xcompile/lib/fpending.c
>> index afa840b8512..e57155e586e 100644
>> --- a/xcompile/lib/fpending.c
>> +++ b/xcompile/lib/fpending.c
>> @@ -41,7 +41,7 @@ __fpending (FILE *fp)
>>    return fp->_IO_write_ptr - fp->_IO_write_base;
>>  #elif defined __sferror || defined __DragonFly__ || defined __ANDROID__
>>    /* FreeBSD, NetBSD, OpenBSD, DragonFly, Mac OS X, Cygwin < 1.7.34, Minix 
>> 3, Android */
>> -  return fp->_p - fp->_bf._base;
>> +  return fp_->_p - fp_->_bf._base;
>>  #elif defined __EMX__                /* emx+gcc */
>>    return fp->_ptr - fp->_buffer;
>>  #elif defined __minix                /* Minix */
>
> IMO, this patch is a no-op:
>
>   - If you are using an Android NDK older than r14b, the definition of
>     'struct __sFILE' is directly in <stdio.h> and thus visible.
>
>   - If you are using an Android NDK r14b or newer, with __ANDROID_API__
>     being < 24, the definition of 'struct __sFILE' has been moved out
>     to <bits/struct_file.h> but is still included from <stdio.h> and is
>     thus visible.

I'm using the NDK r25b; however, bits/struct_file.h in the NDK r25b only
includes:

__BEGIN_DECLS

/** The opaque structure implementing `FILE`. Do not make any assumptions about 
its content. */
struct __sFILE {
#if defined(__LP64__)
  char __private[152];
#else
  char __private[84];
#endif
} __attribute__((aligned(sizeof(void*))));

__END_DECLS

even when __ANDROID_API__ is 19.

> So, in order to investigate this, you need to
>   - explain what you meant by "not works",
>   - run your configure script with option -C,
>   - report the results of
>       grep -i fpending config.cache
>     and
>       grep -i fpending config.status
>   - say which NDK version you're using,
>   - say what is the __ANDROID_API__ value in your environment.

Thanks, I will do this later today.