Failures of `AC CHECK_SIZEOF'

[Ludovic Courtès]

Hi,

We've seen failures of the type "cannot compute sizeof (char)",
resulting from the fact that the executable produced by
`AC_CHECK_SIZEOF' cannot be run because it's linked against a library
that's not in the dynamic linker's search path (`LD_LIBRARY_PATH' or
similar).

For the record, I discussed it with the Autoconf people:

  http://thread.gmane.org/gmane.comp.sysutils.autoconf.general/10250

The solution suggested by Ralf Wildenhues involves using M4 macros as
found in Gnulib to make sure that executables (including those produced
by `configure') get the right `RPATH' so that they can actually be run.

A simpler solution would be to move all `AC_CHECK_SIZEOF' tests earlier
than any `AC_CHECK_LIB' call in `configure.in'.  Unfortunately, we have
a number of `AC_TRY_RUN' tests that would fail later on anyway.

Thanks,
Ludovic.