Re: AC_CHECK_ALIGNOF maximum ??

[Harlan Stenn]

Bob Friesenhahn writes:
> On Thu, 20 Jun 2013, 'Chris Hall' wrote:
> >>> Of course gcc gives __BIGGEST_ALIGNMENT__ for this.  And I guess
> >>> other compilers do something similar...
> >>>
> >>> ...but I cannot help feeling that autoconf should cover this, but
> >>> if it does, I have failed to find where :-(
> >
> >> How would Autoconf portably test for this
> >
> > I have no idea.  Correct me if I am wrong: but I thought Autoconf was
> > there to save humble journeymen like me from having to know that sort
> > of thing ?
> 
> Autoconf figures things out by running the compiler and linker in a 
> portable way.  It does not usually want to run the compiled test 
> program because that does not work for cross-compilation.  There needs 
> to be a way to discover the desired alignment by compiling code.

But that's not really an issue.

The goal here seems to be "make it work easily for somebody who wants to
install the package to a ported system".  There are several autoconf
tests where one must have additional knowledge for cross-compile cases,
and in that case whoever is responsible for doing that port should be
updating the configure.ac file with the information needed by the
target.

H