Re: automake/500: unnecessary -I options in DEFAULT_INCLUDES (make clutter)

[Alexandre Duret-Lutz]

I'm leery of removing -I. in VPATH builds :
  - for one thing relying on BUILT_SOURCES looks fragile because there are
    other ways to ensure built headers (SUBDIRS ordering, explicit 
    dependencies...)
  - also there is something convenient about the way VPATH builds are
    done now: you can temporarily override a distributed source file
    by placing a tweaked copy of that file in the build directory.  I 
    did that only a couple of times, I don't know if I'm alone.
    Anyway for headers this only works with `-I. -I$(srcdir)'.

On the other hand, I agree that `-I. -I.' is unsightly in non-VPATH builds.

So how about something like this instead: use address@hidden@' and expand
it to `-I.' or `-I. -I$(srcdir)' as needed?

2006-08-30  Alexandre Duret-Lutz  <address@hidden>

        For PR automake/501:
        * automake.in (handle_compile) <$default_includes>: Do not output
        the same -I twice.  Use @am__isrc@ instead of ` -I$(srcdir)'.
        * m4/init.m4: Define am__isrc as ` -I$(srcdir)' only in
        non-VPATH builds since we always have `-I.'.
        * tests/subpkg.test: Make sure config headers are found in VPATH
        and non-VPATH builds.

Index: automake.in
===================================================================
RCS file: /cvs/automake/automake/automake.in,v
retrieving revision 1.1629
diff -u -r1.1629 automake.in
--- automake.in 20 Aug 2006 15:46:10 -0000      1.1629
+++ automake.in 30 Aug 2006 07:16:51 -0000
@@ -2301,16 +2301,22 @@
     my $default_includes = '';
     if (! option 'nostdinc')
       {
-       $default_includes = ' -I. -I$(srcdir)';
+       my @incs = ('-I.');
 
        my $var = var 'CONFIG_HEADER';
        if ($var)
          {
            foreach my $hdr (split (' ', $var->variable_value))
              {
-               $default_includes .= ' -I' . dirname ($hdr);
+               push @incs, '-I' . dirname ($hdr);
              }
          }
+       # We want `-I. -I$(srcdir)', but the latter -I is redundant
+       # and unaesthetic in non-VPATH builds.  We use address@hidden@`
+       # instead.  It will be replaced by '-I.' or '-I. -I$(srcdir)'.
+       # Items in CONFIG_HEADER are never in $(srcdir) so it is safe
+       # to just append @address@hidden
+       $default_includes = ' ' . uniq (@incs) . '@am__isrc@';
       }
 
     my (@mostly_rms, @dist_rms);
Index: m4/init.m4
===================================================================
RCS file: /cvs/automake/automake/m4/init.m4,v
retrieving revision 1.65
diff -u -r1.65 init.m4
--- m4/init.m4  19 Aug 2006 13:58:03 -0000      1.65
+++ m4/init.m4  30 Aug 2006 07:16:52 -0000
@@ -30,10 +30,14 @@
 m4_pattern_allow([^AM_[A-Z]+FLAGS$])dnl
 AC_REQUIRE([AM_SET_CURRENT_AUTOMAKE_VERSION])dnl
 AC_REQUIRE([AC_PROG_INSTALL])dnl
-# test to see if srcdir already configured
-if test "`cd $srcdir && pwd`" != "`pwd`" &&
-   test -f $srcdir/config.status; then
-  AC_MSG_ERROR([source directory already configured; run "make distclean" 
there first])
+if test "`cd $srcdir && pwd`" != "`pwd`"; then
+  # Use -I$(srcdir) only when $(srcdir) != ., so that make's output
+  # is not polluted with repeated "-I."
+  AC_SUBST([am__isrc], [' -I$(srcdir)'])_AM_SUBST_NOTMAKE([am__isrc])dnl
+  # test to see if srcdir already configured
+  if test -f $srcdir/config.status; then
+    AC_MSG_ERROR([source directory already configured; run "make distclean" 
there first])
+  fi
 fi
 
 # test whether we have cygpath
Index: tests/subpkg.test
===================================================================
RCS file: /cvs/automake/automake/tests/subpkg.test,v
retrieving revision 1.10
diff -u -r1.10 subpkg.test
--- tests/subpkg.test   14 May 2005 20:28:56 -0000      1.10
+++ tests/subpkg.test   30 Aug 2006 07:16:52 -0000
@@ -1,5 +1,5 @@
 #! /bin/sh
-# Copyright (C) 2002, 2003, 2004  Free Software Foundation, Inc.
+# Copyright (C) 2002, 2003, 2004, 2006  Free Software Foundation, Inc.
 #
 # This file is part of GNU Automake.
 #
@@ -74,6 +74,7 @@
 AM_INIT_AUTOMAKE
 AC_PROG_RANLIB
 AC_PROG_YACC
+AC_CONFIG_HEADERS([config.h:config.hin])
 AC_CONFIG_FILES([Makefile])
 FOO
 EOF
@@ -105,6 +106,7 @@
 cp lib/foo.y lib/bar.y
 
 cat >lib/src/x.c <<'EOF'
+#include <config.h>
 int lib ()
 {
   return 0;
@@ -119,10 +121,12 @@
 $ACLOCAL -I ../m4
 $FGREP 'm4_include([../m4/foo.m4])' aclocal.m4
 $AUTOCONF
+$AUTOHEADER
 $AUTOMAKE -Wno-override --add-missing
 cd ..
 
 ./configure
+$MAKE
 $MAKE distcheck
 test ! -d subpack-1            # make sure distcheck cleans up after itself
 test -f subpack-1.tar.gz

-- 
Alexandre Duret-Lutz