ENABLE_CHECKING in bfd, opcodes, binutils, ld

gas already has this.  Here it enables checking hash table type passed
to elf_link_hash_lookup and elf_link_hash_traverse.

bfd/
	* elf-bfd.h (ENABLE_CHECKING): Define.
	(elf_link_hash_lookup): Abort if wrong type of hash table.
	(elf_link_hash_traverse): Likewise.
	* configure.ac (--enable-checking): Add support.
	* config.in: Regenerate.
	* configure: Regenerate.
binutils/
	* configure.ac (--enable-checking): Add support.
	* config.in: Regenerate.
	* configure: Regenerate.
ld/
	* configure.ac (--enable-checking): Add support.
	* config.in: Regenerate.
	* configure: Regenerate.
opcodes/
	* configure.ac (--enable-checking): Add support.
	* config.in: Regenerate.
	* configure: Regenerate.

opcodes/configure

@@ -799,6 +799,7 @@ with_pic
 enable_fast_install
 with_gnu_ld
 enable_libtool_lock
+enable_checking
 enable_targets
 enable_werror
 enable_build_warnings
@@ -1446,6 +1447,7 @@ Optional Features:
   --enable-fast-install[=PKGS]
                           optimize for fast installation [default=yes]
   --disable-libtool-lock  avoid locking (might break parallel builds)
+  --enable-checking       enable run-time checks
   --enable-targets        alternative target configurations
   --enable-werror         treat compile warnings as errors
   --enable-build-warnings enable build-time compiler warnings
@@ -10806,7 +10808,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 10809 "configure"
+#line 10811 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -10912,7 +10914,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 10915 "configure"
+#line 10917 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11150,6 +11152,22 @@ CC="$lt_save_CC"
 
 
 
+ac_checking=
+. ${srcdir}/../bfd/development.sh
+test "$development" = true && ac_checking=yes
+# Check whether --enable-checking was given.
+if test "${enable_checking+set}" = set; then :
+  enableval=$enable_checking; case "${enableval}" in
+  no|none)  ac_checking= ;;
+  *)	    ac_checking=yes ;;
+esac
+fi
+if test x$ac_checking != x ; then
+
+$as_echo "#define ENABLE_CHECKING 1" >>confdefs.h
+
+fi
+
 # Check whether --enable-targets was given.
 if test "${enable_targets+set}" = set; then :
   enableval=$enable_targets; case "${enableval}" in