Also warn about missing prerequisites as we encounter them (bug #24445).

It can happen that configure bails out in the middle due to some issue
that PSPP cannot directly control; for example, AC_CHECK_SIZEOF exits
unconditionally if it fails.  If this happens then, before, we would fail
to warn about missing required prerequisites that could well have been
the actual cause of the failure, because we only warn about these at
the end of the run.

Now, we warn about missing prerequisites both at time of detection and
in a summary at the end, to head off this problem.

Thanks to Jim Orr for allowing me to notice the problem.

diff --git a/acinclude.m4 b/acinclude.m4
index 11154ee37bfa7ac54f6411bce7ebb6e7b8a680fb..728359ec46a30d317d70ab32ea844bc2e16a7c25 100644 (file)
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -5,9 +5,11 @@ dnl with or without modifications, as long as this notice is preserved.
 
 dnl Prerequisites.
 
-dnl Instead of giving an error about each prerequisite as we encounter it, 
-dnl group them all together at the end of the run, to be user-friendly.
-AC_DEFUN([PSPP_REQUIRED_PREREQ], [pspp_required_prereqs="$pspp_required_prereqs
+dnl Summarize all the missing prerequisites at the end of the run to
+dnl increase user-friendliness.
+AC_DEFUN([PSPP_REQUIRED_PREREQ], 
+  [AC_MSG_WARN([You must install $1 before building PSPP.])
+pspp_required_prereqs="$pspp_required_prereqs
        $1"])
 AC_DEFUN([PSPP_OPTIONAL_PREREQ], [pspp_optional_prereqs="$pspp_optional_prereqs
        $1"])