-## There are exactly 9 lines that should be modified from automake.in to
-## automake, and 10 lines that should be modified from aclocal.in to
-## aclocal; these wors out to 32 and 34 lines of diffs, respectively.
-sc_diff_automake_in_automake:
- @if test `diff $(srcdir)/automake.in automake | wc -l` -ne 32; then \
- echo "found too many diffs between automake.in and automake" 1>&2; \
- diff -c $(srcdir)/automake.in automake; \
- exit 1; \
- fi
-sc_diff_aclocal_in_aclocal:
- @if test `diff $(srcdir)/aclocal.in aclocal | wc -l` -ne 34; then \
- echo "found too many diffs between aclocal.in and aclocal" 1>&2; \
- diff -c $(srcdir)/aclocal.in aclocal; \
- exit 1; \
- fi
-
-## Syntax check with default Perl (on my machine, Perl 5).
-sc_perl_syntax:
- @perllibdir="./lib$(PATH_SEPARATOR)$(srcdir)/lib" $(PERL) -c -w automake
- @perllibdir="./lib$(PATH_SEPARATOR)$(srcdir)/lib" $(PERL) -c -w aclocal
+## There are exactly 8 lines that should be modified from automake.in to
+## automake, and 9 lines that should be modified from aclocal.in to
+## aclocal.
+automake_diff_no = 8
+aclocal_diff_no = 9
+sc_diff_automake sc_diff_aclocal: sc_diff_% :
+ @set +e; tmp=$*-diffs.tmp; \
+ diff -u $(srcdir)/$*.in $* > $$tmp; test $$? -eq 1 || exit 1; \
+ added=`grep -v '^+++ ' $$tmp | grep -c '^+'` || exit 1; \
+ removed=`grep -v '^--- ' $$tmp | grep -c '^-'` || exit 1; \
+ test $$added,$$removed = $($*_diff_no),$($*_diff_no) \
+ || { \
+ echo "Found unexpected diffs between $*.in and $*"; \
+ echo "Lines added: $$added" ; \
+ echo "Lines removed: $$removed"; \
+ cat $$tmp >&2; \
+ exit 1; \
+ } >&1; \
+ rm -f $$tmp