automake: new variable AM_DISTCHECK_DVI_TARGET to override "dvi".

This change fixes https://bugs.gnu.org/8289.

* lib/am/distdir.am (AM_DISTCHECK_DVI_TARGET): define as dvi.
(distcheck): use it, isntead of hardcoding dvi.
* lib/Automake/Variable.pm (%_silent_variable_override): add
AM_DISTCHECK_DVI_TARGET.
* t/distcheck-override-dvi.sh: new test.
* t/list-of-tests.mk (handwritten_TESTS): add it.
* doc/automake.texi (Checking the Distribution): document this.
(Third-Party Makefiles): explicitly mention that
EMPTY_AUTOMAKE_TARGETS is not a built-in or special name.
Various other index entries and wording tweaks.
* NEWS (Distribution): mention this.

2 files changed, 57 insertions, 0 deletions

diff --git a/t/distcheck-override-dvi.sh b/t/distcheck-override-dvi.sh
new file mode 100644
index 000000000..8d83d7e18
--- /dev/null
+++ b/t/distcheck-override-dvi.sh
@@ -0,0 +1,56 @@
+#! /bin/sh
+# Copyright (C) 2011-2020 Free Software Foundation, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2, or (at your option)
+# any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+# Check that we can override the 'dvi' target run as part of distcheck,
+# specifically to be 'html', so that TeX is not required.
+# Related to automake bug#8289.
+
+# TeX and texi2dvi should not be needed or invoked.
+TEX=false TEXI2DVI=false
+export TEX TEXI2DVI
+
+required='makeinfo'
+. test-init.sh
+
+cat >> configure.ac << 'END'
+AC_OUTPUT
+END
+
+cat > Makefile.am << 'END'
+AM_DISTCHECK_DVI_TARGET = html
+info_TEXINFOS = main.texi
+END
+
+# Protect with leading " # " to avoid spurious maintainer-check failures.
+sed 's/^ *# *//' > main.texi << 'END'
+ # \input texinfo
+ # @setfilename main.info
+ # @settitle main
+ #
+ # @node Top
+ # Hello.
+ # @bye
+END
+
+$ACLOCAL
+$AUTOMAKE -a
+$AUTOCONF
+
+./configure
+$MAKE
+$MAKE distcheck
+
+:
diff --git a/t/list-of-tests.mk b/t/list-of-tests.mk
index aab33dca7..43ea245a9 100644
--- a/t/list-of-tests.mk
+++ b/t/list-of-tests.mk
@@ -431,6 +431,7 @@ t/distcheck-writable-srcdir.sh \
 t/distcheck-missing-m4.sh \
 t/distcheck-outdated-m4.sh \
 t/distcheck-no-prefix-or-srcdir-override.sh \
+t/distcheck-override-dvi.sh \
 t/distcheck-override-infodir.sh \
 t/distcheck-pr9579.sh \
 t/distcheck-pr10470.sh \