libgloss: restore multilib settings in subdir makefiles

Commit 754f8def0d ("libgloss: merge stub
arch configure scripts up a level") had an unintended side-effect: the
MULTI* variables in the Makefiles no longer get rewritten at configure
time in the subdirs.  Only the top-level Makefile still is.  This is
because the configure integration of multilib (both the way libgloss
did it manually and the way AM_ENABLE_MULTILIB does it) only rewrites
"Makefile".

We could try propagating the MULTI* variables from libgloss/Makefile
down via FLAGS_TO_PASS, but this runs into a limitation: the multilib
logic uses this variable to switch from libgloss/ to each multilib
libgloss/, and libgloss uses this variable to enter subdirectories.
The latter we want, but the former ends up overridding the Makefile
environment.  We could side-step that with some GNU Make directives,
but it feels like we're getting a bit too deep down the rabbit hole.

Instead, let's call config-ml.in ourselves for each subdir Makefile
that the top-level configure generates.  This restores the previous
behavior and should be less risky in general.

This logic should be unnecessary when/if we switch libgloss over to
a non-recursive Automake build (since all build+install settings are
in the single libgloss/Makefile), but it'll be a while before we can
land that rework, so let's fix this up now.

libgloss/arm/configure

@@ -3926,6 +3926,8 @@ $as_echo X"$file" |
   done
 }
  ;;
+    "cpu-init/Makefile":F)     ac_file=cpu-init/Makefile . ${srcdir}/../../config-ml.in
+   ;;
     "default-1":C)
 # Only add multilib support code if we just rebuilt the top-level
 # Makefile.

libgloss/arm/configure.ac

@@ -62,7 +62,9 @@ AC_SUBST_FILE(host_makefile_frag)
 # Configure cpu init plug-ins
 if test -d "${srcdir}/cpu-init"; then
   subdirs="${subdirs} cpu-init"
-  AC_CONFIG_FILES([cpu-init/Makefile])
+  AC_CONFIG_FILES([cpu-init/Makefile], [dnl
+    ac_file=cpu-init/Makefile . ${srcdir}/../../config-ml.in
+  ])
   AC_SUBST(subdirs)
 fi
 

libgloss/configure

@@ -4794,6 +4794,9 @@ target_makefile_frag_path=$target_makefile_frag
 
 
 
+ac_config_commands="$ac_config_commands default-1"
+
+
 # Default to --enable-multilib
 # Check whether --enable-multilib was given.
 if test "${enable_multilib+set}" = set; then :
@@ -4829,7 +4832,7 @@ if test $cross_compiling = no && test $multilib = yes \
    cross_compiling=maybe
 fi
 
-ac_config_commands="$ac_config_commands default-1"
+ac_config_commands="$ac_config_commands default-2"
 
 
 ac_config_files="$ac_config_files Makefile"
@@ -5554,6 +5557,7 @@ cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
 # INIT-COMMANDS
 #
 AMDEP_TRUE="$AMDEP_TRUE" ac_aux_dir="$ac_aux_dir"
+subdirs="$subdirs"
 
 srcdir="$srcdir"
 host="$host"
@@ -5618,6 +5622,7 @@ do
     "libnosys/Makefile") CONFIG_FILES="$CONFIG_FILES libnosys/Makefile" ;;
     "depfiles") CONFIG_COMMANDS="$CONFIG_COMMANDS depfiles" ;;
     "default-1") CONFIG_COMMANDS="$CONFIG_COMMANDS default-1" ;;
+    "default-2") CONFIG_COMMANDS="$CONFIG_COMMANDS default-2" ;;
     "Makefile") CONFIG_FILES="$CONFIG_FILES Makefile" ;;
 
   *) as_fn_error $? "invalid argument: \`$ac_config_target'" "$LINENO" 5;;
@@ -6347,6 +6352,14 @@ $as_echo X"$file" |
 }
  ;;
     "default-1":C)
+for subdir in $subdirs; do
+  case " $CONFIG_FILES " in
+   *" $subdir/Makefile "*)
+     ac_file=$subdir/Makefile . ${multi_basedir}/config-ml.in
+     ;;
+  esac
+done ;;
+    "default-2":C)
 # Only add multilib support code if we just rebuilt the top-level
 # Makefile.
 case " $CONFIG_FILES " in

libgloss/configure.ac

@@ -330,6 +330,19 @@ target_makefile_frag_path=$target_makefile_frag
 AC_SUBST(target_makefile_frag_path)
 AC_SUBST_FILE(target_makefile_frag)
 
+dnl AM_ENABLE_MULTILIB only processes the top-level Makefile, but we want the
+dnl multilib settings to propagate to all sub-Makefiles that we recurse into
+dnl too.  This can go away if we ever get rid of sub-Makefiles and only use
+dnl Automake + makefile include fragments.
+AC_OUTPUT_COMMANDS([
+for subdir in $subdirs; do
+  case " $CONFIG_FILES " in
+   *" $subdir/Makefile "*)
+     ac_file=$subdir/Makefile . ${multi_basedir}/config-ml.in
+     ;;
+  esac
+done], [subdirs="$subdirs"])
+
 AM_ENABLE_MULTILIB(, ..)
 
 AC_CONFIG_FILES([Makefile])