FYI: 11-freeze-log.patch

[Akim Demaille]

Index: ChangeLog
from  Akim Demaille  <address@hidden>
        
        * Makefile.am (.m4.m4f): Check that freezing produced no output.
        
Index: Makefile.am
--- Makefile.am Thu, 26 Oct 2000 21:03:04 +0200 akim (ace/45_Makefile.a 1.33 
666)
+++ Makefile.am Tue, 31 Oct 2000 02:17:00 +0100 akim (ace/45_Makefile.a 1.33 
666)
@@ -144,8 +144,20 @@
 ## The frozen files.  ##
 ## ------------------ ##
 
+# If freezing produces output, something went wrong: a bad `divert',
+# or an improper paren etc.
+# It may happen that the output does not end with a end of line, hence
+# force an end of line when reporting errors.
 .m4.m4f:
-       $(M4) -I $(srcdir) $(srcdir)/$*.m4 --freeze-state=$*.m4f
+.m4.m4f:
+        $(M4) -I $(srcdir) $(srcdir)/$*.m4 --freeze-state=$*.m4f >freeze.log
+        if grep . freeze.log >/dev/null 2>&1; then \
+          echo "Freezing $(srcdir)/$*.m4 produced output:" >&2; \
+          sed "s,^,$(srcdir)/$*.m4: ," < freeze.log >&2; \
+          echo >&2; \
+          exit 1; \
+        else \
+          rm -f freeze.log; \
+        fi
 
 autoconf.m4f: $(m4sources)