gdb/

	Fix duplicate .o files after omitting libbfd.a.
	* Makefile.in (ALL_TARGET_OBS): Remove corelow.o.
	(SFILES): Add corelow.c.
	(COMMON_OBS): Add corelow.o.
	(ALLDEPFILES): Remove corelow.c.
	* config/alpha/alpha-linux.mh (NATDEPFILES): Remove corelow.o.
	* config/alpha/alpha-osf3.mh: Likewise.
	* config/alpha/fbsd.mh: Likewise.
	* config/arm/nbsdaout.mh: Likewise.
	* config/arm/nbsdelf.mh: Likewise.
	* config/i386/i386gnu.mh: Likewise.
	* config/ia64/hpux.mh: Likewise.
	* config/ia64/linux.mh: Likewise.
	* config/m32r/linux.mh: Likewise.
	* config/m68k/linux.mh: Likewise.
	* config/mips/irix5.mh: Likewise.
	* config/mips/irix6.mh: Likewise.
	* config/pa/hpux.mh: Likewise.
	* config/pa/linux.mh: Likewise.
	* config/powerpc/aix.mh: Likewise.
	* config/sparc/linux.mh: Likewise.
	* config/sparc/linux64.mh: Likewise.
	* config/sparc/sol2.mh: Likewise.
	* config/vax/vax.mh: Likewise.
	* configure.tgt (alpha*-*-freebsd* alpha*-*-kfreebsd*-gnu)
	(alpha*-*-netbsd*, alpha*-*-knetbsd*-gnu, alpha*-*-openbsd*)
	(am33_2.0*-*-linux*, arm*-wince-pe, arm*-*-mingw32ce*, arm*-*-linux*)
	(arm*-*-openbsd*, cris*, frv-*-*, hppa*-*-hpux*, hppa*-*-netbsd*)
	(hppa*-*-openbsd*, i[34567]86-*-dicos*, i[34567]86-*-freebsd*)
	(i[34567]86-*-kfreebsd*-gnu, i[34567]86-*-netbsd*)
	(i[34567]86-*-knetbsd*-gnu, i[34567]86-*-openbsd*, i[34567]86-*-nto*)
	(i[34567]86-*-solaris2.1[0-9]*, x86_64-*-solaris2.1[0-9]*)
	(i[34567]86-*-solaris*, i[34567]86-*-linux*, i[34567]86-*-cygwin*)
	(i[34567]86-*-mingw32*, m68*-*-netbsd*, m68*-*-knetbsd*-gnu)
	(m68*-*-openbsd*, m88*-*-openbsd*, microblaze*-linux-*)
	(microblaze*-*-linux*, mips*-*-linux*, mips*-*-netbsd*)
	(mips*-*-knetbsd*-gnu, mips64*-*-openbsd*, powerpc-*-netbsd*)
	(powerpc-*-knetbsd*-gnu, powerpc-*-openbsd*, powerpc-*-linux*)
	(powerpc64-*-linux*, s390*-*-*, score-*-*, sh*-*-linux*)
	(sh*-*-netbsdelf*, sh*-*-knetbsd*-gnu, sh*-*-openbsd*)
	(sparc*-*-freebsd*, sparc*-*-kfreebsd*-gnu, sparc-*-netbsd*)
	(sparc-*-knetbsd*-gnu, sparc64-*-netbsd*, sparc64-*-knetbsd*-gnu)
	(sparc-*-openbsd*, sparc64-*-openbsd*, tic6x-*-*linux, vax-*-netbsd*)
	(vax-*-knetbsd*-gnu, vax-*-openbsd*, x86_64-*-dicos*, x86_64-*-linux*)
	(x86_64-*-freebsd*, x86_64-*-kfreebsd*-gnu, x86_64-*-netbsd*)
	(x86_64-*-knetbsd*-gnu, x86_64-*-openbsd*, xtensa*-*-linux*): Remove
	corelow.o from gdb_target_obs.
	* corefile.c (core_target): Update the comment on NULL value.
	(core_file_command): Replace error by gdb_assert on CORE_TARGET.
	* corelow.c (sniff_core_bfd): Call error instead of warning on zero
	MATCHES.  Drop YUMMY set on NULL.
	(core_close): Do not call exit_inferior_silent on zero PID.  Do not
	reclaim CORE_DATA if it is already NULL.

24 files changed, 143 insertions, 114 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index c01fefe..4f8b4d3 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,59 @@
+2012-01-10  Jan Kratochvil  <jan.kratochvil@redhat.com>
+
+	Fix duplicate .o files after omitting libbfd.a.
+	* Makefile.in (ALL_TARGET_OBS): Remove corelow.o.
+	(SFILES): Add corelow.c.
+	(COMMON_OBS): Add corelow.o.
+	(ALLDEPFILES): Remove corelow.c.
+	* config/alpha/alpha-linux.mh (NATDEPFILES): Remove corelow.o.
+	* config/alpha/alpha-osf3.mh: Likewise.
+	* config/alpha/fbsd.mh: Likewise.
+	* config/arm/nbsdaout.mh: Likewise.
+	* config/arm/nbsdelf.mh: Likewise.
+	* config/i386/i386gnu.mh: Likewise.
+	* config/ia64/hpux.mh: Likewise.
+	* config/ia64/linux.mh: Likewise.
+	* config/m32r/linux.mh: Likewise.
+	* config/m68k/linux.mh: Likewise.
+	* config/mips/irix5.mh: Likewise.
+	* config/mips/irix6.mh: Likewise.
+	* config/pa/hpux.mh: Likewise.
+	* config/pa/linux.mh: Likewise.
+	* config/powerpc/aix.mh: Likewise.
+	* config/sparc/linux.mh: Likewise.
+	* config/sparc/linux64.mh: Likewise.
+	* config/sparc/sol2.mh: Likewise.
+	* config/vax/vax.mh: Likewise.
+	* configure.tgt (alpha*-*-freebsd* alpha*-*-kfreebsd*-gnu)
+	(alpha*-*-netbsd*, alpha*-*-knetbsd*-gnu, alpha*-*-openbsd*)
+	(am33_2.0*-*-linux*, arm*-wince-pe, arm*-*-mingw32ce*, arm*-*-linux*)
+	(arm*-*-openbsd*, cris*, frv-*-*, hppa*-*-hpux*, hppa*-*-netbsd*)
+	(hppa*-*-openbsd*, i[34567]86-*-dicos*, i[34567]86-*-freebsd*)
+	(i[34567]86-*-kfreebsd*-gnu, i[34567]86-*-netbsd*)
+	(i[34567]86-*-knetbsd*-gnu, i[34567]86-*-openbsd*, i[34567]86-*-nto*)
+	(i[34567]86-*-solaris2.1[0-9]*, x86_64-*-solaris2.1[0-9]*)
+	(i[34567]86-*-solaris*, i[34567]86-*-linux*, i[34567]86-*-cygwin*)
+	(i[34567]86-*-mingw32*, m68*-*-netbsd*, m68*-*-knetbsd*-gnu)
+	(m68*-*-openbsd*, m88*-*-openbsd*, microblaze*-linux-*)
+	(microblaze*-*-linux*, mips*-*-linux*, mips*-*-netbsd*)
+	(mips*-*-knetbsd*-gnu, mips64*-*-openbsd*, powerpc-*-netbsd*)
+	(powerpc-*-knetbsd*-gnu, powerpc-*-openbsd*, powerpc-*-linux*)
+	(powerpc64-*-linux*, s390*-*-*, score-*-*, sh*-*-linux*)
+	(sh*-*-netbsdelf*, sh*-*-knetbsd*-gnu, sh*-*-openbsd*)
+	(sparc*-*-freebsd*, sparc*-*-kfreebsd*-gnu, sparc-*-netbsd*)
+	(sparc-*-knetbsd*-gnu, sparc64-*-netbsd*, sparc64-*-knetbsd*-gnu)
+	(sparc-*-openbsd*, sparc64-*-openbsd*, tic6x-*-*linux, vax-*-netbsd*)
+	(vax-*-knetbsd*-gnu, vax-*-openbsd*, x86_64-*-dicos*, x86_64-*-linux*)
+	(x86_64-*-freebsd*, x86_64-*-kfreebsd*-gnu, x86_64-*-netbsd*)
+	(x86_64-*-knetbsd*-gnu, x86_64-*-openbsd*, xtensa*-*-linux*): Remove
+	corelow.o from gdb_target_obs.
+	* corefile.c (core_target): Update the comment on NULL value.
+	(core_file_command): Replace error by gdb_assert on CORE_TARGET.
+	* corelow.c (sniff_core_bfd): Call error instead of warning on zero
+	MATCHES.  Drop YUMMY set on NULL.
+	(core_close): Do not call exit_inferior_silent on zero PID.  Do not
+	reclaim CORE_DATA if it is already NULL.
+
 2012-01-09  Doug Evans  <dje@google.com>
 
 	* gdbtypes.c (safe_parse_type): Initialize type to keep gcc happy.
diff --git a/gdb/Makefile.in b/gdb/Makefile.in
index a5196a7..25067f1 100644
--- a/gdb/Makefile.in
+++ b/gdb/Makefile.in
@@ -581,7 +581,6 @@ ALL_TARGET_OBS = \
 	remote-m32r-sdi.o remote-mips.o \
 	xcoffread.o \
 	symfile-mem.o \
-	corelow.o \
 	windows-tdep.o \
 	linux-record.o
 
@@ -692,7 +691,7 @@ SFILES = ada-exp.y ada-lang.c ada-typeprint.c ada-valprint.c ada-tasks.c \
 	block.c blockframe.c breakpoint.c buildsym.c \
 	c-exp.y c-lang.c c-typeprint.c c-valprint.c \
 	charset.c cli-out.c coffread.c coff-pe-read.c \
-	complaints.c completer.c continuations.c corefile.c \
+	complaints.c completer.c continuations.c corefile.c corelow.c \
 	cp-abi.c cp-support.c cp-namespace.c cp-valprint.c \
 	d-lang.c d-valprint.c \
 	cp-name-parser.y \
@@ -859,7 +858,7 @@ COMMON_OBS = $(DEPFILES) $(CONFIG_OBS) $(YYOBJ) \
 	auxv.o \
 	bfd-target.o \
 	blockframe.o breakpoint.o findvar.o regcache.o \
-	charset.o continuations.o disasm.o dummy-frame.o dfp.o \
+	charset.o continuations.o corelow.o disasm.o dummy-frame.o dfp.o \
 	source.o value.o eval.o valops.o valarith.o valprint.o printcmd.o \
 	block.o symtab.o psymtab.o symfile.o symmisc.o linespec.o dictionary.o \
 	infcall.o \
@@ -1438,7 +1437,7 @@ ALLDEPFILES = \
 	avr-tdep.c \
 	bfin-linux-tdep.c bfin-tdep.c \
 	bsd-uthread.c bsd-kvm.c \
-	core-regset.c corelow.c \
+	core-regset.c \
 	dcache.c dicos-tdep.c darwin-nat.c \
 	exec.c \
 	fbsd-nat.c \
diff --git a/gdb/config/alpha/alpha-linux.mh b/gdb/config/alpha/alpha-linux.mh
index ddfb19b..15dc989 100644
--- a/gdb/config/alpha/alpha-linux.mh
+++ b/gdb/config/alpha/alpha-linux.mh
@@ -1,6 +1,6 @@
 # Host: Little-endian Alpha running Linux
 NAT_FILE= config/nm-linux.h
-NATDEPFILES= inf-ptrace.o corelow.o alpha-linux-nat.o \
+NATDEPFILES= inf-ptrace.o alpha-linux-nat.o \
 	fork-child.o proc-service.o linux-thread-db.o \
 	linux-nat.o linux-osdata.o linux-fork.o linux-procfs.o
 NAT_CDEPS = $(srcdir)/proc-service.list
diff --git a/gdb/config/alpha/alpha-osf3.mh b/gdb/config/alpha/alpha-osf3.mh
index a65f796..483ef78 100644
--- a/gdb/config/alpha/alpha-osf3.mh
+++ b/gdb/config/alpha/alpha-osf3.mh
@@ -1,6 +1,6 @@
 # Host: Little-endian Alpha running OSF/1-3.x and higher using procfs
 NAT_FILE= nm-osf3.h
-NATDEPFILES= corelow.o alpha-nat.o fork-child.o \
+NATDEPFILES= alpha-nat.o fork-child.o \
 	solib-osf.o procfs.o proc-api.o proc-events.o proc-flags.o \
 	proc-why.o dec-thread.o
 NAT_CLIBS= -lpthreaddebug
diff --git a/gdb/config/alpha/fbsd.mh b/gdb/config/alpha/fbsd.mh
index 3aac410..6d1fe29 100644
--- a/gdb/config/alpha/fbsd.mh
+++ b/gdb/config/alpha/fbsd.mh
@@ -1,6 +1,6 @@
 # Host: FreeBSD/alpha
 NATDEPFILES= fork-child.o inf-ptrace.o \
 	fbsd-nat.o alphabsd-nat.o bsd-kvm.o \
-	corelow.o core-regset.o
+	core-regset.o
 
 LOADLIBES= -lkvm
diff --git a/gdb/config/arm/nbsdaout.mh b/gdb/config/arm/nbsdaout.mh
index b06044b..d10bd04 100644
--- a/gdb/config/arm/nbsdaout.mh
+++ b/gdb/config/arm/nbsdaout.mh
@@ -1,3 +1,3 @@
 # Host: NetBSD/arm
-NATDEPFILES= fork-child.o inf-ptrace.o corelow.o armnbsd-nat.o \
+NATDEPFILES= fork-child.o inf-ptrace.o armnbsd-nat.o \
 	solib-sunos.o
diff --git a/gdb/config/arm/nbsdelf.mh b/gdb/config/arm/nbsdelf.mh
index 8ff679f..4efb8a3 100644
--- a/gdb/config/arm/nbsdelf.mh
+++ b/gdb/config/arm/nbsdelf.mh
@@ -1,2 +1,2 @@
 # Host: NetBSD/arm
-NATDEPFILES= fork-child.o inf-ptrace.o corelow.o armnbsd-nat.o
+NATDEPFILES= fork-child.o inf-ptrace.o armnbsd-nat.o
diff --git a/gdb/config/i386/i386gnu.mh b/gdb/config/i386/i386gnu.mh
index d4e09d9..d85744b 100644
--- a/gdb/config/i386/i386gnu.mh
+++ b/gdb/config/i386/i386gnu.mh
@@ -1,5 +1,5 @@
 # Host: Intel 386 running the GNU Hurd
-NATDEPFILES= i386gnu-nat.o gnu-nat.o corelow.o core-regset.o fork-child.o \
+NATDEPFILES= i386gnu-nat.o gnu-nat.o core-regset.o fork-child.o \
 	     notify_S.o process_reply_S.o msg_reply_S.o \
 	     msg_U.o exc_request_U.o exc_request_S.o
 
diff --git a/gdb/config/ia64/hpux.mh b/gdb/config/ia64/hpux.mh
index b75763b..7bbfab4 100644
--- a/gdb/config/ia64/hpux.mh
+++ b/gdb/config/ia64/hpux.mh
@@ -1,3 +1,3 @@
 # Host: ia64 running HP-UX
-NATDEPFILES= fork-child.o inf-ttrace.o corelow.o ia64-hpux-nat.o \
+NATDEPFILES= fork-child.o inf-ttrace.o ia64-hpux-nat.o \
         solib-ia64-hpux.o
diff --git a/gdb/config/ia64/linux.mh b/gdb/config/ia64/linux.mh
index 5114899..c72929c 100644
--- a/gdb/config/ia64/linux.mh
+++ b/gdb/config/ia64/linux.mh
@@ -1,7 +1,7 @@
 # Host: Intel IA-64 running GNU/Linux
 
 NAT_FILE= config/nm-linux.h
-NATDEPFILES= inf-ptrace.o fork-child.o corelow.o \
+NATDEPFILES= inf-ptrace.o fork-child.o \
 	core-regset.o ia64-linux-nat.o \
 	proc-service.o linux-thread-db.o \
 	linux-nat.o linux-osdata.o linux-fork.o \
diff --git a/gdb/config/m32r/linux.mh b/gdb/config/m32r/linux.mh
index b4849ae..32a4428 100644
--- a/gdb/config/m32r/linux.mh
+++ b/gdb/config/m32r/linux.mh
@@ -1,7 +1,7 @@
 # Host: M32R based machine running GNU/Linux
 
 NAT_FILE= config/nm-linux.h
-NATDEPFILES= inf-ptrace.o fork-child.o corelow.o	\
+NATDEPFILES= inf-ptrace.o fork-child.o				\
 	m32r-linux-nat.o proc-service.o linux-thread-db.o	\
 	linux-nat.o linux-osdata.o linux-fork.o linux-procfs.o
 NAT_CDEPS = $(srcdir)/proc-service.list
diff --git a/gdb/config/m68k/linux.mh b/gdb/config/m68k/linux.mh
index 3a95828..b116819 100644
--- a/gdb/config/m68k/linux.mh
+++ b/gdb/config/m68k/linux.mh
@@ -2,7 +2,7 @@
 
 NAT_FILE= config/nm-linux.h
 NATDEPFILES= inf-ptrace.o fork-child.o \
-	corelow.o m68klinux-nat.o \
+	m68klinux-nat.o \
 	proc-service.o linux-thread-db.o \
 	linux-nat.o linux-osdata.o linux-fork.o linux-procfs.o
 NAT_CDEPS = $(srcdir)/proc-service.list
diff --git a/gdb/config/mips/irix5.mh b/gdb/config/mips/irix5.mh
index 8d07221..7ab5e11 100644
--- a/gdb/config/mips/irix5.mh
+++ b/gdb/config/mips/irix5.mh
@@ -1,3 +1,3 @@
 # Host: SGI Iris running irix 5.x
-NATDEPFILES= fork-child.o irix5-nat.o corelow.o procfs.o \
+NATDEPFILES= fork-child.o irix5-nat.o procfs.o \
 	proc-api.o proc-events.o proc-flags.o proc-why.o
diff --git a/gdb/config/mips/irix6.mh b/gdb/config/mips/irix6.mh
index de212b2..28a67eb 100644
--- a/gdb/config/mips/irix6.mh
+++ b/gdb/config/mips/irix6.mh
@@ -1,3 +1,3 @@
 # Host: SGI Iris running irix 6.x
-NATDEPFILES= fork-child.o irix5-nat.o corelow.o procfs.o \
+NATDEPFILES= fork-child.o irix5-nat.o procfs.o \
 	proc-api.o proc-events.o proc-flags.o proc-why.o
diff --git a/gdb/config/pa/hpux.mh b/gdb/config/pa/hpux.mh
index 7b4fd07..e88bddb 100644
--- a/gdb/config/pa/hpux.mh
+++ b/gdb/config/pa/hpux.mh
@@ -1,3 +1,3 @@
 # Host: PA-RISC HP-UX
 NATDEPFILES= fork-child.o inf-ptrace.o inf-ttrace.o \
-	hppa-hpux-nat.o corelow.o somread.o
+	hppa-hpux-nat.o somread.o
diff --git a/gdb/config/pa/linux.mh b/gdb/config/pa/linux.mh
index 4ed8cbf..e9b7114 100644
--- a/gdb/config/pa/linux.mh
+++ b/gdb/config/pa/linux.mh
@@ -1,6 +1,6 @@
 # Host: Hewlett-Packard PA-RISC machine, running Linux
 NAT_FILE= config/nm-linux.h
-NATDEPFILES= inf-ptrace.o fork-child.o corelow.o \
+NATDEPFILES= inf-ptrace.o fork-child.o \
 	hppa-linux-nat.o proc-service.o linux-thread-db.o \
 	linux-nat.o linux-osdata.o linux-fork.o \
 	linux-procfs.o
diff --git a/gdb/config/powerpc/aix.mh b/gdb/config/powerpc/aix.mh
index 50484eb..d007fff 100644
--- a/gdb/config/powerpc/aix.mh
+++ b/gdb/config/powerpc/aix.mh
@@ -3,7 +3,7 @@
 NAT_FILE= config/rs6000/nm-rs6000.h
 
 # aix-thread.o is not listed in NATDEPFILES as it is pulled in by configure.
-NATDEPFILES= fork-child.o inf-ptrace.o corelow.o rs6000-nat.o \
+NATDEPFILES= fork-child.o inf-ptrace.o rs6000-nat.o \
 	     xcoffsolib.o
 
 # When compiled with cc, for debugging, this argument should be passed.
diff --git a/gdb/config/sparc/linux.mh b/gdb/config/sparc/linux.mh
index a9a768c..25c4ad5 100644
--- a/gdb/config/sparc/linux.mh
+++ b/gdb/config/sparc/linux.mh
@@ -1,7 +1,7 @@
 # Host: GNU/Linux SPARC
 NAT_FILE= config/nm-linux.h
 NATDEPFILES= sparc-nat.o sparc-linux-nat.o \
-	corelow.o core-regset.o fork-child.o inf-ptrace.o \
+	core-regset.o fork-child.o inf-ptrace.o \
 	proc-service.o linux-thread-db.o \
 	linux-nat.o linux-osdata.o linux-fork.o \
 	linux-procfs.o
diff --git a/gdb/config/sparc/linux64.mh b/gdb/config/sparc/linux64.mh
index 30eef2b..363e19b 100644
--- a/gdb/config/sparc/linux64.mh
+++ b/gdb/config/sparc/linux64.mh
@@ -1,7 +1,7 @@
 # Host: GNU/Linux UltraSPARC
 NAT_FILE= config/nm-linux.h
 NATDEPFILES= sparc-nat.o sparc64-nat.o sparc64-linux-nat.o \
-	corelow.o core-regset.o \
+	core-regset.o \
 	fork-child.o inf-ptrace.o \
 	proc-service.o linux-thread-db.o \
 	linux-nat.o linux-osdata.o linux-fork.o \
diff --git a/gdb/config/sparc/sol2.mh b/gdb/config/sparc/sol2.mh
index f9efd31..9f91583 100644
--- a/gdb/config/sparc/sol2.mh
+++ b/gdb/config/sparc/sol2.mh
@@ -1,5 +1,5 @@
 # Host: Solaris SPARC & UltraSPARC
 NAT_FILE= nm-sol2.h
 NATDEPFILES= sparc-sol2-nat.o \
-	corelow.o core-regset.o fork-child.o \
+	core-regset.o fork-child.o \
 	procfs.o proc-api.o proc-events.o proc-flags.o proc-why.o
diff --git a/gdb/config/vax/vax.mh b/gdb/config/vax/vax.mh
index 69c548d..d8d7f6f 100644
--- a/gdb/config/vax/vax.mh
+++ b/gdb/config/vax/vax.mh
@@ -1,2 +1,2 @@
 # Host: VAX running 4.2BSD or Ultrix
-NATDEPFILES= vax-nat.o fork-child.o inf-ptrace.o corelow.o
+NATDEPFILES= vax-nat.o fork-child.o inf-ptrace.o
diff --git a/gdb/configure.tgt b/gdb/configure.tgt
index 5542af0..178b7fc 100644
--- a/gdb/configure.tgt
+++ b/gdb/configure.tgt
@@ -44,19 +44,18 @@ alpha*-*-linux*)
 alpha*-*-freebsd* | alpha*-*-kfreebsd*-gnu)
 	# Target: FreeBSD/alpha
 	gdb_target_obs="alpha-tdep.o alpha-mdebug-tdep.o alphabsd-tdep.o \
-			alphafbsd-tdep.o corelow.o solib-svr4.o"
+			alphafbsd-tdep.o solib-svr4.o"
 	;;
 alpha*-*-netbsd* | alpha*-*-knetbsd*-gnu)
 	# Target: NetBSD/alpha
 	gdb_target_obs="alpha-tdep.o alpha-mdebug-tdep.o alphabsd-tdep.o \
-			alphanbsd-tdep.o nbsd-tdep.o corelow.o \
-			solib-svr4.o"
+			alphanbsd-tdep.o nbsd-tdep.o solib-svr4.o"
 	;;
 alpha*-*-openbsd*)
 	# Target: OpenBSD/alpha
 	gdb_target_obs="alpha-tdep.o alpha-mdebug-tdep.o alphabsd-tdep.o \
 			alphanbsd-tdep.o alphaobsd-tdep.o nbsd-tdep.o \
-			obsd-tdep.o corelow.o solib-svr4.o"
+			obsd-tdep.o solib-svr4.o"
 	;;
 alpha*-*-*)
 	# Target: Alpha
@@ -66,18 +65,18 @@ alpha*-*-*)
 am33_2.0*-*-linux*)
 	# Target: Matsushita mn10300 (AM33) running Linux
 	gdb_target_obs="mn10300-tdep.o mn10300-linux-tdep.o linux-tdep.o \
-			corelow.o solib-svr4.o"
+			solib-svr4.o"
 	;;
 
 arm*-wince-pe | arm*-*-mingw32ce*)
 	# Target: ARM based machine running Windows CE (win32)
-	gdb_target_obs="arm-tdep.o arm-wince-tdep.o corelow.o"
+	gdb_target_obs="arm-tdep.o arm-wince-tdep.o"
 	build_gdbserver=yes
 	;;
 arm*-*-linux*)
 	# Target: ARM based machine running GNU/Linux
 	gdb_target_obs="arm-tdep.o arm-linux-tdep.o glibc-tdep.o \
-			solib-svr4.o symfile-mem.o corelow.o linux-tdep.o"
+			solib-svr4.o symfile-mem.o linux-tdep.o"
 	build_gdbserver=yes
 	;;
 arm*-*-netbsd* | arm*-*-knetbsd*-gnu)
@@ -87,7 +86,7 @@ arm*-*-netbsd* | arm*-*-knetbsd*-gnu)
 arm*-*-openbsd*)
 	# Target: OpenBSD/arm
 	gdb_target_obs="arm-tdep.o armbsd-tdep.o armobsd-tdep.o obsd-tdep.o \
-			corelow.o solib-svr4.o"
+			solib-svr4.o"
 	;;
 arm*-*-symbianelf*)
 	# Target: SymbianOS/arm
@@ -119,13 +118,12 @@ bfin-*-*)
 
 cris*)
 	# Target: CRIS
-	gdb_target_obs="cris-tdep.o corelow.o solib-svr4.o"
+	gdb_target_obs="cris-tdep.o solib-svr4.o"
 	;;
 
 frv-*-*)
 	# Target: Fujitsu FRV processor
-	gdb_target_obs="frv-tdep.o frv-linux-tdep.o linux-tdep.o \
-			solib-frv.o corelow.o"
+	gdb_target_obs="frv-tdep.o frv-linux-tdep.o linux-tdep.o solib-frv.o"
 	gdb_sim=../sim/frv/libsim.a
 	;;
 
@@ -142,8 +140,7 @@ h8300-*-*)
 
 hppa*-*-hpux*)
 	# Target: HP PA-RISC running hpux
-	gdb_target_obs="hppa-tdep.o hppa-hpux-tdep.o corelow.o \
-			solib-som.o solib-pa64.o"
+	gdb_target_obs="hppa-tdep.o hppa-hpux-tdep.o solib-som.o solib-pa64.o"
 	;;
 hppa*-*-linux*)
 	# Target: HP PA-RISC running Linux
@@ -152,13 +149,11 @@ hppa*-*-linux*)
 	;;
 hppa*-*-netbsd*)
 	# Target: NetBSD/hppa
-	gdb_target_obs="hppa-tdep.o hppabsd-tdep.o hppanbsd-tdep.o \
-			corelow.o solib-svr4.o"
+	gdb_target_obs="hppa-tdep.o hppabsd-tdep.o hppanbsd-tdep.o solib-svr4.o"
 	;;
 hppa*-*-openbsd*)
 	# Target: OpenBSD/hppa
-	gdb_target_obs="hppa-tdep.o hppabsd-tdep.o hppaobsd-tdep.o \
-			corelow.o solib-svr4.o"
+	gdb_target_obs="hppa-tdep.o hppabsd-tdep.o hppaobsd-tdep.o solib-svr4.o"
 	;;
 hppa*-*-*)
 	# Target: HP PA-RISC
@@ -176,46 +171,43 @@ i[34567]86-*-darwin*)
 	;;
 i[34567]86-*-dicos*)
 	# Target: DICOS/i386
-	gdb_target_obs="i386-tdep.o i387-tdep.o \
-			dicos-tdep.o i386-dicos-tdep.o \
-			corelow.o"
+	gdb_target_obs="i386-tdep.o i387-tdep.o dicos-tdep.o i386-dicos-tdep.o"
 	;;
 i[34567]86-*-freebsd* | i[34567]86-*-kfreebsd*-gnu)
 	# Target: FreeBSD/i386
 	gdb_target_obs="i386-tdep.o i387-tdep.o i386bsd-tdep.o i386fbsd-tdep.o \
-			bsd-uthread.o corelow.o solib-svr4.o"
+			bsd-uthread.o solib-svr4.o"
 	;;
 i[34567]86-*-netbsd* | i[34567]86-*-knetbsd*-gnu)
 	# Target: NetBSD/i386
 	gdb_target_obs="i386-tdep.o i387-tdep.o i386bsd-tdep.o i386nbsd-tdep.o \
-			nbsd-tdep.o corelow.o solib-svr4.o"
+			nbsd-tdep.o solib-svr4.o"
 	;;
 i[34567]86-*-openbsd*)
 	# Target: OpenBSD/i386
 	gdb_target_obs="i386-tdep.o i387-tdep.o i386bsd-tdep.o i386obsd-tdep.o \
-			bsd-uthread.o corelow.o solib-svr4.o"
+			bsd-uthread.o solib-svr4.o"
 	;;
 i[34567]86-*-nto*)
 	# Target: Intel 386 running qnx6.
-	gdb_target_obs="i386-tdep.o i387-tdep.o corelow.o solib-svr4.o \
+	gdb_target_obs="i386-tdep.o i387-tdep.o solib-svr4.o \
 			i386-nto-tdep.o nto-tdep.o"
 	build_gdbserver=yes
 	;;
 i[34567]86-*-solaris2.1[0-9]* | x86_64-*-solaris2.1[0-9]*)
 	# Target: Solaris x86_64
 	gdb_target_obs="i386-tdep.o i387-tdep.o amd64-tdep.o amd64-sol2-tdep.o \
-			i386-sol2-tdep.o sol2-tdep.o \
-			corelow.o solib-svr4.o"
+			i386-sol2-tdep.o sol2-tdep.o solib-svr4.o"
 	;;
 i[34567]86-*-solaris*)
 	# Target: Solaris x86
 	gdb_target_obs="i386-tdep.o i387-tdep.o i386-sol2-tdep.o sol2-tdep.o \
-			corelow.o solib-svr4.o"
+			solib-svr4.o"
 	;;
 i[34567]86-*-linux*)
 	# Target: Intel 386 running GNU/Linux
 	gdb_target_obs="i386-tdep.o i386-linux-tdep.o glibc-tdep.o i387-tdep.o \
-			solib-svr4.o symfile-mem.o corelow.o \
+			solib-svr4.o symfile-mem.o \
 			linux-tdep.o linux-record.o"
 	if test "x$enable_64_bit_bfd" = "xyes"; then
 	    # Target: GNU/Linux x86-64
@@ -230,13 +222,13 @@ i[34567]86-*-gnu*)
 i[34567]86-*-cygwin*)
 	# Target: Intel 386 running win32
 	gdb_target_obs="i386-tdep.o i386-cygwin-tdep.o i387-tdep.o \
-			corelow.o windows-tdep.o"
+			windows-tdep.o"
 	build_gdbserver=yes
 	;;
 i[34567]86-*-mingw32*)
 	# Target: Intel 386 running win32
 	gdb_target_obs="i386-tdep.o i386-cygwin-tdep.o i387-tdep.o \
-			corelow.o windows-tdep.o"
+			windows-tdep.o"
 	build_gdbserver=yes
 	;;
 i[34567]86-*-*)
@@ -311,18 +303,16 @@ m68*-*-linux*)
 	;;
 m68*-*-netbsd* | m68*-*-knetbsd*-gnu)
 	# Target: NetBSD/m68k
-	gdb_target_obs="m68k-tdep.o m68kbsd-tdep.o \
-			corelow.o solib-svr4.o"
+	gdb_target_obs="m68k-tdep.o m68kbsd-tdep.o solib-svr4.o"
 	;;
 m68*-*-openbsd*)
 	# Target: OpenBSD/m68k
-	gdb_target_obs="m68k-tdep.o m68kbsd-tdep.o \
-			corelow.o solib-svr4.o"
+	gdb_target_obs="m68k-tdep.o m68kbsd-tdep.o solib-svr4.o"
 	;;
 
 m88*-*-openbsd*)
 	# Target: OpenBSD/m88k
-	gdb_target_obs="m88k-tdep.o corelow.o"
+	gdb_target_obs="m88k-tdep.o"
 	;;
 
 mep-*-*)
@@ -334,8 +324,7 @@ mep-*-*)
 microblaze*-linux-*|microblaze*-*-linux*)
 	# Target: Xilinx MicroBlaze running Linux
 	gdb_target_obs="microblaze-tdep.o microblaze-linux-tdep.o microblaze-rom.o \
-			monitor.o dsrec.o solib-svr4.o corelow.o \
-			symfile-mem.o linux-tdep.o"
+			monitor.o dsrec.o solib-svr4.o symfile-mem.o linux-tdep.o"
 	gdb_sim=../sim/microblaze/libsim.a
 	;;
 microblaze*-*-*)
@@ -355,21 +344,18 @@ mips*-sgi-irix6*)
 mips*-*-linux*)
 	# Target: Linux/MIPS
 	gdb_target_obs="mips-tdep.o mips-linux-tdep.o glibc-tdep.o \
-			corelow.o solib-svr4.o symfile-mem.o \
-			linux-tdep.o"
+			solib-svr4.o symfile-mem.o linux-tdep.o"
 	gdb_sim=../sim/mips/libsim.a
 	build_gdbserver=yes
 	;;
 mips*-*-netbsd* | mips*-*-knetbsd*-gnu)
 	# Target: MIPS running NetBSD
-	gdb_target_obs="mips-tdep.o mipsnbsd-tdep.o \
-			corelow.o solib-svr4.o nbsd-tdep.o"
+	gdb_target_obs="mips-tdep.o mipsnbsd-tdep.o solib-svr4.o nbsd-tdep.o"
 	gdb_sim=../sim/mips/libsim.a
 	;;
 mips64*-*-openbsd*)
 	# Target: OpenBSD/mips64
-	gdb_target_obs="mips-tdep.o mips64obsd-tdep.o \
-			corelow.o solib-svr4.o"
+	gdb_target_obs="mips-tdep.o mips64obsd-tdep.o solib-svr4.o"
 	;;
 mips*-*-elf)
 	# Target: MIPS ELF
@@ -396,13 +382,13 @@ mt-*-*)
 powerpc-*-netbsd* | powerpc-*-knetbsd*-gnu)
 	# Target: NetBSD/powerpc
 	gdb_target_obs="rs6000-tdep.o ppc-sysv-tdep.o ppcnbsd-tdep.o \
-			corelow.o solib-svr4.o"
+			solib-svr4.o"
 	gdb_sim=../sim/ppc/libsim.a
 	;;
 powerpc-*-openbsd*)
 	# Target: OpenBSD/powerpc
 	gdb_target_obs="rs6000-tdep.o ppc-sysv-tdep.o ppcobsd-tdep.o \
-			corelow.o solib-svr4.o"
+			solib-svr4.o"
 	;;
 powerpc-*-aix* | rs6000-*-*)
 	# Target: PowerPC running AIX
@@ -413,7 +399,7 @@ powerpc-*-linux* | powerpc64-*-linux*)
 	# Target: PowerPC running Linux
 	gdb_target_obs="rs6000-tdep.o ppc-linux-tdep.o ppc-sysv-tdep.o \
 			solib-svr4.o solib-spu.o spu-multiarch.o \
-			corelow.o symfile-mem.o linux-tdep.o"
+			symfile-mem.o linux-tdep.o"
 	gdb_sim=../sim/ppc/libsim.a
 	build_gdbserver=yes
 	;;
@@ -428,7 +414,7 @@ powerpc*-*-*)
 
 s390*-*-*)
 	# Target: S390 running Linux
-	gdb_target_obs="s390-tdep.o solib-svr4.o corelow.o linux-tdep.o"
+	gdb_target_obs="s390-tdep.o solib-svr4.o linux-tdep.o"
 	build_gdbserver=yes
 	;;
 
@@ -440,7 +426,7 @@ rx-*-elf)
 
 score-*-*)
 	# Target: S+core embedded system
-	gdb_target_obs="score-tdep.o corelow.o"
+	gdb_target_obs="score-tdep.o"
 	if test -f ../sim/score/Makefile; then
 	  gdb_sim=../sim/score/libsim.a
 	fi
@@ -451,19 +437,18 @@ sh*-*-linux*)
 	# Target: GNU/Linux Super-H
 	gdb_target_obs="sh-tdep.o sh64-tdep.o sh-linux-tdep.o monitor.o \
 			dsrec.o solib-svr4.o symfile-mem.o \
-			glibc-tdep.o corelow.o linux-tdep.o"
+			glibc-tdep.o linux-tdep.o"
 	gdb_sim=../sim/sh/libsim.a
 	build_gdbserver=yes
 	;;
 sh*-*-netbsdelf* | sh*-*-knetbsd*-gnu)
 	# Target: NetBSD/sh
-	gdb_target_obs="sh-tdep.o shnbsd-tdep.o corelow.o solib-svr4.o"
+	gdb_target_obs="sh-tdep.o shnbsd-tdep.o solib-svr4.o"
 	gdb_sim=../sim/sh/libsim.a
 	;;
 sh*-*-openbsd*)
 	# Target: OpenBSD/sh
-	gdb_target_obs="sh-tdep.o sh64-tdep.o shnbsd-tdep.o \
-			corelow.o solib-svr4.o"
+	gdb_target_obs="sh-tdep.o sh64-tdep.o shnbsd-tdep.o solib-svr4.o"
 	;;
 sh64-*-elf*)
 	# Target: Renesas/Super-H 64 bit with simulator
@@ -497,31 +482,27 @@ sparc64-*-linux*)
 sparc*-*-freebsd* | sparc*-*-kfreebsd*-gnu)
 	# Target: FreeBSD/sparc64
 	gdb_target_obs="sparc-tdep.o sparc64-tdep.o sparc64fbsd-tdep.o \
-			corelow.o solib-svr4.o"
+			solib-svr4.o"
 	;;
 sparc-*-netbsd* | sparc-*-knetbsd*-gnu)
 	# Target: NetBSD/sparc
-	gdb_target_obs="sparc-tdep.o sparcnbsd-tdep.o nbsd-tdep.o \
-			corelow.o solib-svr4.o"
+	gdb_target_obs="sparc-tdep.o sparcnbsd-tdep.o nbsd-tdep.o solib-svr4.o"
 	;;
 sparc64-*-netbsd* | sparc64-*-knetbsd*-gnu)
 	# Target: NetBSD/sparc64
 	gdb_target_obs="sparc64-tdep.o sparc64nbsd-tdep.o sparc-tdep.o \
-			sparcnbsd-tdep.o nbsd-tdep.o \
-			corelow.o solib-svr4.o"
+			sparcnbsd-tdep.o nbsd-tdep.o solib-svr4.o"
 	;;
 sparc-*-openbsd*)
 	# Target: OpenBSD/sparc
 	gdb_target_obs="sparc-tdep.o sparcnbsd-tdep.o sparcobsd-tdep.o \
-			nbsd-tdep.o obsd-tdep.o bsd-uthread.o \
-			corelow.o solib-svr4.o"
+			nbsd-tdep.o obsd-tdep.o bsd-uthread.o solib-svr4.o"
 	;;
 sparc64-*-openbsd*)
 	# Target: OpenBSD/sparc64
 	gdb_target_obs="sparc64-tdep.o sparc64nbsd-tdep.o sparc64obsd-tdep.o \
 			sparc-tdep.o sparcnbsd-tdep.o sparcobsd-tdep.o \
-			nbsd-tdep.o obsd-tdep.o bsd-uthread.o \
-			corelow.o solib-svr4.o"
+			nbsd-tdep.o obsd-tdep.o bsd-uthread.o solib-svr4.o"
 	;;
 sparc-*-solaris2.[0-6] | sparc-*-solaris2.[0-6].*)
 	# Target: Solaris SPARC
@@ -552,7 +533,7 @@ spu*-*-*)
 tic6x-*-*linux)
 	# Target: GNU/Linux TI C6x
 	gdb_target_obs="tic6x-tdep.o tic6x-linux-tdep.o solib-dsbt.o \
-			glibc-tdep.o corelow.o linux-tdep.o"
+			glibc-tdep.o linux-tdep.o"
 	;;
 
 tic6x-*-*)
@@ -574,12 +555,11 @@ v850*-*-elf)
 
 vax-*-netbsd* | vax-*-knetbsd*-gnu)
 	# Target: NetBSD/vax
-	gdb_target_obs="vax-tdep.o vaxnbsd-tdep.o \
-			corelow.o solib-svr4.o"
+	gdb_target_obs="vax-tdep.o vaxnbsd-tdep.o solib-svr4.o"
 	;;
 vax-*-openbsd*)
 	# Target: OpenBSD/vax
-	gdb_target_obs="vax-tdep.o vaxobsd-tdep.o corelow.o"
+	gdb_target_obs="vax-tdep.o vaxobsd-tdep.o"
 	;;
 vax-*-*)
 	# Target: VAX running 4.2BSD or Ultrix
@@ -596,22 +576,20 @@ x86_64-*-darwin*)
 x86_64-*-dicos*)
 	# Target: DICOS/x86-64
 	gdb_target_obs="amd64-tdep.o i386-tdep.o i387-tdep.o \
-			dicos-tdep.o i386-dicos-tdep.o amd64-dicos-tdep.o \
-			corelow.o"
+			dicos-tdep.o i386-dicos-tdep.o amd64-dicos-tdep.o"
 	;;
 x86_64-*-linux*)
 	# Target: GNU/Linux x86-64
 	gdb_target_obs="amd64-tdep.o amd64-linux-tdep.o i386-tdep.o \
 			i387-tdep.o i386-linux-tdep.o glibc-tdep.o \
-			solib-svr4.o corelow.o symfile-mem.o linux-tdep.o \
-			linux-record.o"
+			solib-svr4.o symfile-mem.o linux-tdep.o linux-record.o"
 	build_gdbserver=yes
 	;;
 x86_64-*-freebsd* | x86_64-*-kfreebsd*-gnu)
 	# Target: FreeBSD/amd64
 	gdb_target_obs="amd64-tdep.o amd64fbsd-tdep.o i386-tdep.o \
 			i387-tdep.o i386bsd-tdep.o i386fbsd-tdep.o \
-			bsd-uthread.o corelow.o solib-svr4.o"
+			bsd-uthread.o solib-svr4.o"
 	;;
 x86_64-*-mingw*)
         # Target: MingW/amd64
@@ -623,18 +601,18 @@ x86_64-*-mingw*)
 x86_64-*-netbsd* | x86_64-*-knetbsd*-gnu)
 	# Target: NetBSD/amd64
 	gdb_target_obs="amd64-tdep.o amd64nbsd-tdep.o i386-tdep.o i387-tdep.o \
-			nbsd-tdep.o corelow.o solib-svr4.o"
+			nbsd-tdep.o solib-svr4.o"
 	;;
 x86_64-*-openbsd*)
 	# Target: OpenBSD/amd64
 	gdb_target_obs="amd64-tdep.o amd64obsd-tdep.o i386-tdep.o \
 			i387-tdep.o i386bsd-tdep.o i386obsd-tdep.o \
-			bsd-uthread.o corelow.o solib-svr4.o"
+			bsd-uthread.o solib-svr4.o"
 	;;
 xtensa*-*-linux*)	gdb_target=linux
 	# Target: GNU/Linux Xtensa
 	gdb_target_obs="xtensa-tdep.o xtensa-config.o xtensa-linux-tdep.o \
-			solib-svr4.o corelow.o symfile-mem.o linux-tdep.o"
+			solib-svr4.o symfile-mem.o linux-tdep.o"
 	build_gdbserver=yes
 	;;
 xtensa*)
diff --git a/gdb/corefile.c b/gdb/corefile.c
index 1741e9c..986e4f5 100644
--- a/gdb/corefile.c
+++ b/gdb/corefile.c
@@ -60,7 +60,7 @@ static int exec_file_hook_count = 0;		/* Size of array.  */
 
 bfd *core_bfd = NULL;
 
-/* corelow.c target (if included for this gdb target).  */
+/* corelow.c target.  It is never NULL after GDB initialization.  */
 
 struct target_ops *core_target;
 
@@ -72,8 +72,7 @@ core_file_command (char *filename, int from_tty)
 {
   dont_repeat ();		/* Either way, seems bogus.  */
 
-  if (core_target == NULL)
-    error (_("GDB can't read core files on this machine."));
+  gdb_assert (core_target != NULL);
 
   if (!filename)
     (core_target->to_detach) (core_target, filename, from_tty);
diff --git a/gdb/corelow.c b/gdb/corelow.c
index f98814a..3e0c7cd 100644
--- a/gdb/corelow.c
+++ b/gdb/corelow.c
@@ -129,8 +129,7 @@ default_core_sniffer (struct core_fns *our_fns, bfd *abfd)
 }
 
 /* Walk through the list of core functions to find a set that can
-   handle the core file open on ABFD.  Default to the first one in the
-   list if nothing matches.  Returns pointer to set that is
+   handle the core file open on ABFD.  Returns pointer to set that is
    selected.  */
 
 static struct core_fns *
@@ -159,15 +158,9 @@ sniff_core_bfd (bfd *abfd)
 	       bfd_get_filename (abfd), matches);
     }
   else if (matches == 0)
-    {
-      warning (_("\"%s\": no core file handler "
-		 "recognizes format, using default"),
-	       bfd_get_filename (abfd));
-    }
-  if (yummy == NULL)
-    {
-      yummy = core_file_fns;
-    }
+    error (_("\"%s\": no core file handler recognizes format"),
+	   bfd_get_filename (abfd));
+
   return (yummy);
 }
 
@@ -211,15 +204,19 @@ core_close (int quitting)
       int pid = ptid_get_pid (inferior_ptid);
       inferior_ptid = null_ptid;    /* Avoid confusion from thread
 				       stuff.  */
-      exit_inferior_silent (pid);
+      if (pid != 0)
+	exit_inferior_silent (pid);
 
       /* Clear out solib state while the bfd is still open.  See
          comments in clear_solib in solib.c.  */
       clear_solib ();
 
-      xfree (core_data->sections);
-      xfree (core_data);
-      core_data = NULL;
+      if (core_data)
+	{
+	  xfree (core_data->sections);
+	  xfree (core_data);
+	  core_data = NULL;
+	}
       core_has_fake_pid = 0;
 
       name = bfd_get_filename (core_bfd);