Thu Jul 27 17:38:35 2000 Andrew Cagney <cagney@b1.cygnus.com>

        * configure.in (targetfile): Ignore TM_FILE, don't just issue
        warning.
        (tm_h, xm_h, nm_h, GDB_TM_FILE, GDB_XM_FILE, GDB_NM_FILE): Define.
        * acconfig.h (GDB_XM_FILE, GDB_TM_FILE, GDB_NM_FILE): Add.
        * config/nm-empty.h: Delete.
        * defs.h (xm.h, nm.h, tm.h): Only include when GDB_XM_FILE,
        GDB_NM_FILE or GDB_TM_FILE defined.
        * Makefile.in (defs_h): Replace tm.h, xm.h and nm.h with tm_h,
        xm_h and nm_h macro that are defined by configure.
        (tm_h, xm_h, tm_h): New.
        * configure, config.in: Regenerate
        * TODO: Update.

8 files changed, 115 insertions, 57 deletions

diff --git a/gdb/Makefile.in b/gdb/Makefile.in
index 9be5d368ae4..9d4aa8c9212 100644
--- a/gdb/Makefile.in
+++ b/gdb/Makefile.in
@@ -548,7 +548,10 @@ command_h =	command.h
 gdbcmd_h =	gdbcmd.h $(command_h)
 
 call_cmds_h =	call-cmds.h
-defs_h =	defs.h xm.h tm.h nm.h config.status config.h gdbarch.h ui-file.h
+xm_h =		@xm_h@
+tm_h =		@tm_h@
+nm_h =		@nm_h@
+defs_h =	defs.h $(xm_h) $(tm_h) $(nm_h) config.status config.h gdbarch.h ui-file.h
 
 top_h =		top.h
 inferior_h =	inferior.h $(breakpoint_h)
diff --git a/gdb/TODO b/gdb/TODO
index 63ee0b4a2a1..e72a3a74ef1 100644
--- a/gdb/TODO
+++ b/gdb/TODO
@@ -351,12 +351,6 @@ fundamental architectural change.
 Add built-by, build-date, tm, xm, nm and anything else into gdb binary
 so that you can see how the GDB was created.
 
-Some of these (*m.h) would be added to the generated config.h.  That
-in turn would fix a long standing bug where by the build process many
-not notice a changed tm.h file.  Since everything depends on config.h,
-a change to *m.h forces a change to config.h and, consequently forces
-a rebuild.
-
 --
 
 Add an "info bfd" command that displays supported object formats,
diff --git a/gdb/acconfig.h b/gdb/acconfig.h
index f9e2b32a264..5b3531aa951 100644
--- a/gdb/acconfig.h
+++ b/gdb/acconfig.h
@@ -125,3 +125,11 @@
 /* Multi-arch enabled. */
 #undef GDB_MULTI_ARCH
 
+/* hostfile */
+#undef GDB_XM_FILE
+
+/* targetfile */
+#undef GDB_TM_FILE
+
+/* nativefile */
+#undef GDB_NM_FILE
diff --git a/gdb/config.in b/gdb/config.in
index c8509750098..1571a9fc800 100644
--- a/gdb/config.in
+++ b/gdb/config.in
@@ -144,6 +144,15 @@
 /* Multi-arch enabled. */
 #undef GDB_MULTI_ARCH
 
+/* hostfile */
+#undef GDB_XM_FILE
+
+/* targetfile */
+#undef GDB_TM_FILE
+
+/* nativefile */
+#undef GDB_NM_FILE
+
 /* Define if you have the __argz_count function.  */
 #undef HAVE___ARGZ_COUNT
 
diff --git a/gdb/config/nm-empty.h b/gdb/config/nm-empty.h
deleted file mode 100644
index 7069d8c8a4e..00000000000
--- a/gdb/config/nm-empty.h
+++ /dev/null
@@ -1,2 +0,0 @@
-/* This is just a dummy file to symlink to when GDB is configured as a
-   cross-only debugger.  */
diff --git a/gdb/configure b/gdb/configure
index ac046a88047..88fc963f42b 100755
--- a/gdb/configure
+++ b/gdb/configure
@@ -7524,6 +7524,7 @@ case "${GDB_MULTI_ARCH}" in
     GDB_MULTI_ARCH_PURE )
 	if test x"${targetfile}" != x ; then
 	    echo "configure: warning: "GDB: Ingoring TM_FILE in ${target_makefile_frag}"" 1>&2
+	    targetfile=""
 	fi ;;
     *)  { echo "configure: error: "GDB: Unknown GDB_MULTI_ARCH value ${GDB_MULTI_ARCH}"" 1>&2; exit 1; };;
 esac
@@ -7537,34 +7538,56 @@ fi
 
 
 # If hostfile (XM_FILE) and/or targetfile (TM_FILE) and/or nativefile
-# (NAT_FILE) is not set in config/*/*.m[ht] files, we don't make the
-# corresponding links.  But we have to remove the xm.h files and tm.h
-# files anyway, e.g. when switching from "configure host" to
-# "configure none".
+# (NAT_FILE) is not set in config/*/*.m[ht] files, we link to an empty
+# version.
 
 files=
 links=
+
 rm -f xm.h
+xm_h=""
 if test "${hostfile}" != ""; then
-files="${files} config/${gdb_host_cpu}/${hostfile}"
-links="${links} xm.h"
+    xm_h=xm.h
+    GDB_XM_FILE="config/${gdb_host_cpu}/${hostfile}"
+    files="${files} ${GDB_XM_FILE}"
+    links="${links} xm.h"
+    cat >> confdefs.h <<EOF
+#define GDB_XM_FILE ${GDB_XM_FILE}
+EOF
+
 fi
+
+
 rm -f tm.h
+tm_h=""
 if test "${targetfile}" != ""; then
-files="${files} config/${gdb_target_cpu}/${targetfile}"
-links="${links} tm.h"
+    tm_h=tm.h
+    GDB_TM_FILE="config/${gdb_target_cpu}/${targetfile}"
+    files="${files} ${GDB_TM_FILE}"
+    links="${links} tm.h"
+    cat >> confdefs.h <<EOF
+#define GDB_TM_FILE ${GDB_TM_FILE}
+EOF
+
 fi
+
+
 rm -f nm.h
+nm_h=""
 if test "${nativefile}" != ""; then
-files="${files} config/${gdb_host_cpu}/${nativefile}"
-links="${links} nm.h"
-else
-# A cross-only configuration.
-files="${files} config/nm-empty.h"
-links="${links} nm.h"
+    nm_h=nm.h
+    GDB_NM_FILE="config/${gdb_host_cpu}/${nativefile}"
+    files="${files} ${GDB_NM_FILE}"
+    links="${links} nm.h"
+    cat >> confdefs.h <<EOF
+#define GDB_NM_FILE ${GDB_NM_FILE}
+EOF
+
 fi
+
+
 echo $ac_n "checking whether ln -s works""... $ac_c" 1>&6
-echo "configure:7568: checking whether ln -s works" >&5
+echo "configure:7591: checking whether ln -s works" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_LN_S'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -7588,12 +7611,12 @@ fi
 
 
 echo $ac_n "checking for Cygwin environment""... $ac_c" 1>&6
-echo "configure:7592: checking for Cygwin environment" >&5
+echo "configure:7615: checking for Cygwin environment" >&5
 if eval "test \"`echo '$''{'ac_cv_cygwin'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 7597 "configure"
+#line 7620 "configure"
 #include "confdefs.h"
 
 int main() {
@@ -7604,7 +7627,7 @@ int main() {
 return __CYGWIN__;
 ; return 0; }
 EOF
-if { (eval echo configure:7608: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:7631: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   ac_cv_cygwin=yes
 else
@@ -7621,19 +7644,19 @@ echo "$ac_t""$ac_cv_cygwin" 1>&6
 CYGWIN=
 test "$ac_cv_cygwin" = yes && CYGWIN=yes
 echo $ac_n "checking for mingw32 environment""... $ac_c" 1>&6
-echo "configure:7625: checking for mingw32 environment" >&5
+echo "configure:7648: checking for mingw32 environment" >&5
 if eval "test \"`echo '$''{'ac_cv_mingw32'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 7630 "configure"
+#line 7653 "configure"
 #include "confdefs.h"
 
 int main() {
 return __MINGW32__;
 ; return 0; }
 EOF
-if { (eval echo configure:7637: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:7660: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   ac_cv_mingw32=yes
 else
@@ -7652,7 +7675,7 @@ test "$ac_cv_mingw32" = yes && MINGW32=yes
 
 
 echo $ac_n "checking for executable suffix""... $ac_c" 1>&6
-echo "configure:7656: checking for executable suffix" >&5
+echo "configure:7679: checking for executable suffix" >&5
 if eval "test \"`echo '$''{'ac_cv_exeext'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -7662,7 +7685,7 @@ else
   rm -f conftest*
   echo 'int main () { return 0; }' > conftest.$ac_ext
   ac_cv_exeext=
-  if { (eval echo configure:7666: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; }; then
+  if { (eval echo configure:7689: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; }; then
     for file in conftest.*; do
       case $file in
       *.c | *.o | *.obj | *.ilk | *.pdb) ;;
@@ -7954,6 +7977,9 @@ s%@host_makefile_frag@%%g
 s%@target_makefile_frag@%%g
 s%@frags@%$frags%g
 s%@SUBDIRS@%$SUBDIRS%g
+s%@xm_h@%$xm_h%g
+s%@tm_h@%$tm_h%g
+s%@nm_h@%$nm_h%g
 s%@LN_S@%$LN_S%g
 s%@EXEEXT@%$EXEEXT%g
 s%@subdirs@%$subdirs%g
diff --git a/gdb/configure.in b/gdb/configure.in
index 624a77f82c3..2ab19f71641 100644
--- a/gdb/configure.in
+++ b/gdb/configure.in
@@ -1042,6 +1042,7 @@ case "${GDB_MULTI_ARCH}" in
     GDB_MULTI_ARCH_PURE )
 	if test x"${targetfile}" != x ; then
 	    AC_MSG_WARN("GDB: Ingoring TM_FILE in ${target_makefile_frag}")
+	    targetfile=""
 	fi ;;
     *)  AC_MSG_ERROR("GDB: Unknown GDB_MULTI_ARCH value ${GDB_MULTI_ARCH}");;
 esac
@@ -1055,32 +1056,45 @@ fi
 AC_SUBST(SUBDIRS)
 
 # If hostfile (XM_FILE) and/or targetfile (TM_FILE) and/or nativefile
-# (NAT_FILE) is not set in config/*/*.m[ht] files, we don't make the
-# corresponding links.  But we have to remove the xm.h files and tm.h
-# files anyway, e.g. when switching from "configure host" to
-# "configure none".
+# (NAT_FILE) is not set in config/*/*.m[ht] files, we link to an empty
+# version.
 
 files=
 links=
+
 rm -f xm.h
+xm_h=""
 if test "${hostfile}" != ""; then
-files="${files} config/${gdb_host_cpu}/${hostfile}"
-links="${links} xm.h"
+    xm_h=xm.h
+    GDB_XM_FILE="config/${gdb_host_cpu}/${hostfile}"
+    files="${files} ${GDB_XM_FILE}"
+    links="${links} xm.h"
+    AC_DEFINE_UNQUOTED(GDB_XM_FILE, ${GDB_XM_FILE})
 fi
+AC_SUBST(xm_h)
+
 rm -f tm.h
+tm_h=""
 if test "${targetfile}" != ""; then
-files="${files} config/${gdb_target_cpu}/${targetfile}"
-links="${links} tm.h"
+    tm_h=tm.h
+    GDB_TM_FILE="config/${gdb_target_cpu}/${targetfile}"
+    files="${files} ${GDB_TM_FILE}"
+    links="${links} tm.h"
+    AC_DEFINE_UNQUOTED(GDB_TM_FILE, ${GDB_TM_FILE})
 fi
+AC_SUBST(tm_h)
+
 rm -f nm.h
+nm_h=""
 if test "${nativefile}" != ""; then
-files="${files} config/${gdb_host_cpu}/${nativefile}"
-links="${links} nm.h"
-else
-# A cross-only configuration.
-files="${files} config/nm-empty.h"
-links="${links} nm.h"
+    nm_h=nm.h
+    GDB_NM_FILE="config/${gdb_host_cpu}/${nativefile}"
+    files="${files} ${GDB_NM_FILE}"
+    links="${links} nm.h"
+    AC_DEFINE_UNQUOTED(GDB_NM_FILE, ${GDB_NM_FILE})
 fi
+AC_SUBST(nm_h)
+
 AC_PROG_LN_S
 
 AC_LINK_FILES($files, $links)
diff --git a/gdb/defs.h b/gdb/defs.h
index 6e4a22241f5..1ff7d663964 100644
--- a/gdb/defs.h
+++ b/gdb/defs.h
@@ -79,7 +79,7 @@
 #define GDB_MULTI_ARCH_TM 2
 
 /* The target is pure multi-arch.  The MULTI-ARCH vector provides all
-   definitions.  "tm.h" is NOT included. */
+   definitions.  "tm.h" is linked to an empty file. */
 
 #define GDB_MULTI_ARCH_PURE 3
 
@@ -710,29 +710,35 @@ enum val_prettyprint
   };
 
 
-/* Host machine definition.  This will be a symlink to one of the
-   xm-*.h files, built by the `configure' script.  */
+/* Optional host machine definition.  Pure autoconf targets will not
+   need a "xm.h" file.  This will be a symlink to one of the xm-*.h
+   files, built by the `configure' script.  */
 
+#ifdef GDB_XM_FILE
 #include "xm.h"
+#endif
 
-/* Native machine support.  This will be a symlink to one of the
-   nm-*.h files, built by the `configure' script.  */
+/* Optional native machine support.  Non-native (and possibly pure
+   multi-arch) targets do not need a "nm.h" file.  This will be a
+   symlink to one of the nm-*.h files, built by the `configure'
+   script.  */
 
+#ifdef GDB_NM_FILE
 #include "nm.h"
+#endif
 
-/* Target machine definition.  This will be a symlink to one of the
+/* Optional target machine definition.  Pure multi-arch configurations
+   do not need a "tm.h" file.  This will be a symlink to one of the
    tm-*.h files, built by the `configure' script.  */
 
-#if (GDB_MULTI_ARCH < GDB_MULTI_ARCH_PURE)
+#ifdef GDB_TM_FILE
 #include "tm.h"
 #endif
 
 /* GDB_MULTI_ARCH is normally set by configure.in using information
    from configure.tgt or the config/%/%.mt Makefile fragment.  Since
-   some targets have defined it in their tm.h file, don't provide a
-   default until after "tm.h" has been included.  (In the above #if,
-   GDB_MULTI_ARCH will be interpreted as zero if it is not
-   defined). */
+   some targets have defined it in their "tm.h" file, delay providing
+   a default definition until after "tm.h" has been included.. */
 
 #ifndef GDB_MULTI_ARCH
 #define GDB_MULTI_ARCH 0