Fix creation of nm.h when configure is changed

My earlier patch -- commit c5adaa192 ("Fix creation of stamp-h by
gdb's configure script") -- broke the creation of nm.h.  In
particular, configure removes nm.h, so if you touch configure and
rebuild, nothing will re-create the link, breaking the build.

This patch fixes the bug, and also updates configure.ac to use
AC_CONFIG_LINKS, rather than the obsolete AC_LINK_FILES.

Finally, I noticed that gcore is in generated_files in the
Makefile.in.  I think this is incorrect, as generated_files is only
needed for files that can be the target of a #include.  So, this patch
removes it.

gdb/ChangeLog
2019-10-21  Tom Tromey  <tom@tromey.com>

	* configure.ac (nm.h): Conditionally create nm.h link.  Subst
	NM_H.   Use AC_CONFIG_LINKS.
	* configure: Rebuild.
	* Makefile.in (NM_H): New variable.
	(generated_files): Add NM_H.  Remove gcore.
	(nm.h, stamp-nmh): New targets.

Change-Id: I8dd539785d52455e85389425e4bb996c8a127a0e

1 files changed, 9 insertions, 19 deletions

diff --git a/gdb/configure b/gdb/configure
index 70ce52f..737b426 100755
--- a/gdb/configure
+++ b/gdb/configure
@@ -626,6 +626,7 @@ LIBOBJS
 GCORE_TRANSFORM_NAME
 GDB_TRANSFORM_NAME
 XSLTPROC
+NM_H
 GDB_NM_FILE
 LTLIBBABELTRACE
 LIBBABELTRACE
@@ -17556,28 +17557,25 @@ $as_echo "$as_me: WARNING: babeltrace is missing or unusable; GDB is unable to r
   fi
 fi
 
-# If nativefile (NAT_FILE) is not set in configure.nat, we link to an
-# empty version.
-
-files=
-links=
-
+NM_H=
 rm -f nm.h
 if test "${nativefile}" != ""; then
     case "${nativefile}" in
       nm-*.h ) GDB_NM_FILE="config/${gdb_host_cpu}/${nativefile}" ;;
       * ) GDB_NM_FILE="${nativefile}"
     esac
-    files="${files} ${GDB_NM_FILE}"
-    links="${links} nm.h"
+    ac_config_links="$ac_config_links nm.h:$GDB_NM_FILE"
+
 
 cat >>confdefs.h <<_ACEOF
 #define GDB_NM_FILE "${GDB_NM_FILE}"
 _ACEOF
 
+    NM_H=nm.h
 fi
 
 
+
 for ac_prog in xsltproc
 do
   # Extract the first word of "$ac_prog", so it can be a program name with args.
@@ -17631,16 +17629,6 @@ if test "x$USE_MAINTAINER_MODE" = xyes; then
 fi
 
 
-ac_sources="$files"
-ac_dests="$links"
-while test -n "$ac_sources"; do
-  set $ac_dests; ac_dest=$1; shift; ac_dests=$*
-  set $ac_sources; ac_source=$1; shift; ac_sources=$*
-  ac_config_links_1="$ac_config_links_1 $ac_dest:$ac_source"
-done
-ac_config_links="$ac_config_links $ac_config_links_1"
-
-
 
 
 
@@ -18406,6 +18394,7 @@ cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
 # INIT-COMMANDS
 #
 ac_aux_dir=$ac_aux_dir DEPDIR=$DEPDIR
+GDB_NM_FILE=$GDB_NM_FILE
 
 _ACEOF
 
@@ -18418,7 +18407,7 @@ do
     "config.h") CONFIG_HEADERS="$CONFIG_HEADERS config.h:config.in" ;;
     "depdir") CONFIG_COMMANDS="$CONFIG_COMMANDS depdir" ;;
     "jit-reader.h") CONFIG_FILES="$CONFIG_FILES jit-reader.h:jit-reader.in" ;;
-    "$ac_config_links_1") CONFIG_LINKS="$CONFIG_LINKS $ac_config_links_1" ;;
+    "nm.h") CONFIG_LINKS="$CONFIG_LINKS nm.h:$GDB_NM_FILE" ;;
     "gcore") CONFIG_FILES="$CONFIG_FILES gcore" ;;
     "Makefile") CONFIG_FILES="$CONFIG_FILES Makefile" ;;
     "gdb-gdb.gdb") CONFIG_FILES="$CONFIG_FILES gdb-gdb.gdb" ;;
@@ -19053,6 +19042,7 @@ $as_echo "$as_me: executing $ac_file commands" >&6;}
   case $ac_file$ac_mode in
     "config.h":H) echo > stamp-h ;;
     "depdir":C) $SHELL $ac_aux_dir/mkinstalldirs $DEPDIR ;;
+    "nm.h":L) echo > stamp-nmh ;;
     "gcore":F) chmod +x gcore ;;
 
   esac