Re: AC_SYS_LARGEFILE

On 2023-09-19 01:52, Sébastien Hinderer wrote:
> Are you saying that there should normally not  be any
> undef in the config headers for macros whose name starts with a _ sign?

No, it's normal when Autoconf is used as intended. What's not normal is 
that your package is including <config.h> after including standard headers.

Since macro names starting with "_" can affect how standard headers 
behave, these macro definitions need to be done before including any 
standard headers, and this is partly why <config.h> should be included 
first.

Although _FILE_OFFSET_BITS is one example of such a macro (so you'll 
need to set it using "gcc -D" or equivalent), there are likely many 
other examples and they all need to be treated similarly.