Index: Makefile.am
===================================================================
--- Makefile.am	(revision 249171)
+++ Makefile.am	(working copy)
@@ -42,7 +42,8 @@ AM_GOCFLAGS = -I $(libgodir)
 AM_LDFLAGS = -L $(libgodir) -L $(libgodir)/.libs
 GOLINK = $(GOCOMPILER) $(GOCFLAGS) $(AM_GOCFLAGS) $(LDFLAGS) $(AM_LDFLAGS) -o $@
 
-cmdsrcdir = $(srcdir)/../libgo/go/cmd
+libgosrcdir = $(srcdir)/../libgo/go
+cmdsrcdir = $(libgosrcdir)/cmd
 
 go_cmd_go_files = \
 	$(cmdsrcdir)/go/alldocs.go \
@@ -131,6 +132,90 @@ install-exec-local: cgo$(EXEEXT)
 uninstall-local:
 	rm -f $(DESTDIR)$(libexecsubdir)/cgo$(exeext)
 
+# Run tests using the go tool, and frob the output to look like that
+# generated by DejaGNU.  The main output of this is two files:
+# gotools.sum and gotools.log.
+
+# check-head starts generating the log files in DejaGNU format.  This
+# is a separate target so that the date is approximately when we start
+# running the tests.
+check-head:
+	@echo "Test Run By $${USER} on `date`" > gotools.head
+	@echo "Native configuration is $(host_triplet)" >> gotools.head
+	@echo >> gotools.head
+	@echo "		=== gotools tests ===" >> gotools.head
+	@echo >> gotools.head
+
+# check-gccgo is a little shell script that executes gccgo with the
+# options to pick up the newly built libgo.
+check-gccgo: Makefile
+	rm -f $@
+	echo "#!/bin/sh" > $@
+	abs_libgodir=`cd $(libgodir) && $(PWD_COMMAND)`; \
+	echo "$(GOCOMPILE)" '"$$@"' "-I $${abs_libgodir} -L $${abs_libgodir} -L $${abs_libgodir}/.libs" >> $@
+	chmod +x $@
+
+# CHECK_ENV sets up the environment to run the newly built go tool.
+CHECK_ENV = \
+	PATH=`echo $(abs_builddir):$${PATH} | sed 's,::*,:,g;s,^:*,,;s,:*$$,,'`; \
+	export PATH; \
+	GCCGO="$(abs_builddir)/check-gccgo"; \
+	export GCCGO; \
+	GCCGOTOOLDIR="$(abs_builddir)"; \
+	export GCCGOTOOLDIR; \
+	GO_TESTING_GOTOOLS=yes; \
+	export GO_TESTING_GOTOOLS; \
+	abs_libgodir=`cd $(libgodir) && $(PWD_COMMAND)`; \
+	LD_LIBRARY_PATH=`echo $${abs_libgodir}/.libs:$${LD_LIBRARY_PATH} | sed 's,::*,:,g;s,^:*,,;s,:*$$,,'`; \
+	export LD_LIBRARY_PATH;
+
+# check-go-tools runs `go test cmd/go` in our environment.
+check-go-tool: go$(EXEEXT) check-head check-gccgo
+	rm -rf check-go-dir
+	$(MKDIR_P) check-go-dir/src/cmd/go
+	cp $(cmdsrcdir)/go/*.go check-go-dir/src/cmd/go/
+	cp $(libgodir)/zstdpkglist.go check-go-dir/src/cmd/go/
+	cp zdefaultcc.go check-go-dir/src/cmd/go/
+	cp -r $(cmdsrcdir)/go/testdata check-go-dir/src/cmd/go/
+	$(CHECK_ENV) \
+	GOPATH=`cd check-go-dir && $(PWD_COMMAND)`; \
+	export GOPATH; \
+	(cd check-go-dir/src/cmd/go && $(abs_builddir)/go$(EXEEXT) test -test.short -test.v) >& cmd_go-testlog || true
+	grep '^--- ' gotools-log
+	if grep '^--- FAIL' gotools-log >/dev/null 2>&1; then exit 1; fi
+
+# The check targets runs the tests and assembles the output files.
+check: check-head check-go-tool
+	mv gotools.head gotools.sum
+	cp gotools.sum gotools.log
+	for file in cmd_go-testlog; do \
+	  testname=`echo $${file} | sed -e 's/-testlog//' -e 's|_|/|'`; \
+	  echo "Running $${testname}" >> gotools.sum; \
+	  echo "Running $${testname}" >> gotools.log; \
+	  sed -e 's/^--- \(.*\) ([^)]*)$$/\1/' < $${file} >> gotools.log; \
+	  grep '^--- ' $${file} | sed -e 's/^--- \(.*\) ([^)]*)$$/\1/' -e 's/SKIP/UNTESTED/' >> gotools.sum; \
+	done
+	@echo >> gotools.sum
+	@echo "		=== gotools Summary ===" >> gotools.sum
+	pass=`grep -c '^PASS' gotools.sum`; \
+	if test "$${pass}" -ne "0"; then \
+	  echo "# of expected passes		$${pass}" >> gotools.sum; \
+	fi
+	fail=`grep -c '^FAIL' gotools.sum`; \
+	if test "$${fail}" -ne "0"; then \
+	  echo "# of unexpected failures	$${fail}" >> gotools.sum; \
+	fi
+	untested=`grep -c '^UNTESTED' gotools.sum`; \
+	if test "$${untested}" -ne "0"; then \
+	  echo "# of untested testcases		$${untested}" >> gotools.sum; \
+	fi
+	echo `echo $(GOC_FOR_TARGET) | sed -e 's/ .*//'`  `$(GOC_FOR_TARGET) -v 2>&1 | grep " version" | sed -n -e 's/.* \(version.*$$\)/\1/p'` >> gotools.sum
+	echo >> gotools.log
+	echo "runtest completed at `date`" >> gotools.log
+	if grep '^FAIL' gotools.sum >/dev/null 2>&1; then exit 1; fi
+
+.PHONY: check check-head check-go-tool
+
 else
 
 # For a non-native build we have to build the programs using a
@@ -140,3 +225,6 @@ else
 # the go/build package.  Figure this out later.
 
 endif
+
+mostlyclean-local:
+	rm -rf check-go-dir