Re: document how to override test results

[Bruno Haible]

Ralf Wildenhues wrote:
> the user
> will prefer the simplest and fastest way to get over a build failure.

So, please document the possible ways of getting over a build failure.
Currently, the manual is silent about this.

> I think it would be better if Automake stated plainly:
> 
>    Prefer using $(variable) over @address@hidden  That enables the user
>    to override the setting of the variable at `make' run time.
> 
> I thought the manual already said this, but I can't find it right now.

This is only a partial answer to the problem. It helps only if one of
the AC_PROG_*, AC_CHECK_PROG*, AC_CHECK_TOOL* macros guessed wrong.

What if the user wants to override the results of the following
autoconf tests?
  - AC_CHECK_TYPES([uid_t])
  - AC_CHECK_LIB([nsl], [gethostname])
  - AC_FUNC_GETGROUPS
  - AC_FUNC_MKTIME
  - AC_CHECK_FUNC([foo])
  - AC_REPLACE_FUNCS([foo])
  - AC_CHECK_HEADER([stdbool.h])
  - AC_CHECK_DECL([errno],,,[#include <errno.h>])
  - AC_CHECK_MEMBER([struct stat.st_blksize])
  - AC_SYS_LARGEFILE
  - AC_CANONICAL_HOST

Currently only a few autoconf wizards know how to do it. The doc does
not say it.

Bruno