Do not terminate default test runs on test failure.

This patch is an updated version of
<https://sourceware.org/ml/libc-alpha/2014-01/msg00198.html> and
<https://sourceware.org/ml/libc-alpha/2014-03/msg00180.html>.

Normal practice for software testsuites is that rather than
terminating immediately when a test fails, they continue running and
report at the end on how many tests passed or failed.

The principle behind the glibc testsuite stopping on failure was
probably that the expected state is no failures and so any failure
indicates a problem such as miscompilation.  In practice, while this
is fairly close to true for native testing on x86_64 and x86 (kernel
bugs and race conditions can still cause intermittent failures), it's
less likely to be the case on other platforms, and so people testing
glibc run the testsuite with "make -k" and then examine the logs to
determine whether the failures are what they expect to fail on that
platform, possibly with some automation for the comparison.

This patch switches the glibc testsuite to the normal convention of
not stopping on failure - unless you use stop-on-test-failure=y, in
which case it behaves essentially as it did before (and does not
generate overall test summaries on failure).  Instead, the summary
tests.sum may contain tests that FAILed.  At the end of the test run,
any FAIL or ERROR lines from tests.sum are printed, and then it exits
with error status if there were any such lines.  In addition, build
failures will also cause the test run to stop - this has the
justification that those *do* indicate serious problems that should be
promptly fixed and aren't generally hard to fix (but apart from that,
avoiding the build stopping on those failures seems harder).

Note that unlike the previous patches in this series, this *does*
require people with automation around testing glibc to change their
processes - either to start using tests.sum / xtests.sum to track
failures and compare them with expectations (with or without also
using "make -k" and examining "make" logs to identify build failures),
or else to use stop-on-test-failure=y and ignore the new tests.sum /
xtests.sum mechanism.  (If all you check is the exit status from "make
check", no changes are needed unless you want to avoid test runs
continuing after the first failure.)

Tested x86_64.

	* scripts/evaluate-test.sh: Handle fourth argument to determine
	whether test run should stop on failure.
	* Makeconfig (stop-on-test-failure): New variable.
	(evaluate-test): Pass fourth argument to evaluate-test.sh based on
	$(stop-on-test-failure).
	* Makefile (tests): Give a summary of results from testing and
	exit with failure status if they include an ERROR or FAIL.
	(xtests): Likewise.
	* manual/install.texi (Configuring and compiling): Mention
	stop-on-test-failure=y.
	* INSTALL: Regenerated.

7 files changed, 59 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index 99d2cae..fb61ad2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,17 @@
+2014-03-14  Joseph Myers  <joseph@codesourcery.com>
+
+	* scripts/evaluate-test.sh: Handle fourth argument to determine
+	whether test run should stop on failure.
+	* Makeconfig (stop-on-test-failure): New variable.
+	(evaluate-test): Pass fourth argument to evaluate-test.sh based on
+	$(stop-on-test-failure).
+	* Makefile (tests): Give a summary of results from testing and
+	exit with failure status if they include an ERROR or FAIL.
+	(xtests): Likewise.
+	* manual/install.texi (Configuring and compiling): Mention
+	stop-on-test-failure=y.
+	* INSTALL: Regenerated.
+
 2014-03-14  Roland McGrath  <roland@hack.frob.com>
 
 	* scripts/versionlist.awk: New file.
diff --git a/INSTALL b/INSTALL
index f845940..13fb678 100644
--- a/INSTALL
+++ b/INSTALL
@@ -203,6 +203,12 @@ The tests (and later installation) use some pre-existing files of the
 system such as `/etc/passwd', `/etc/nsswitch.conf' and others.  These
 files must all contain correct and sensible content.
 
+   Normally, `make check' will run all the tests before reporting all
+problems found and exiting with error status if any problems occurred.
+You can specify `stop-on-test-failure=y' when running `make check' to
+make the test run stop and exit with an error status immediately when a
+failure occurs.
+
    To format the `GNU C Library Reference Manual' for printing, type
 `make dvi'.  You need a working TeX installation to do this.  The
 distribution builds the on-line formatted version of the manual, as
diff --git a/Makeconfig b/Makeconfig
index fa9fb63..3338ab6 100644
--- a/Makeconfig
+++ b/Makeconfig
@@ -601,6 +601,12 @@ run-built-tests = yes
 endif
 endif
 
+# Whether to stop immediately when a test fails.  Nonempty means to
+# stop, empty means not to stop.
+ifndef stop-on-test-failure
+stop-on-test-failure =
+endif
+
 # How to run a program we just linked with our library.
 # The program binary is assumed to be $(word 2,$^).
 built-program-file = $(dir $(word 2,$^))$(notdir $(word 2,$^))
@@ -1092,6 +1098,7 @@ test-xfail-name = $(strip $(patsubst %.out, %, $(patsubst $(objpfx)%, %, $@)))
 # XPASS or XFAIL rather than PASS or FAIL.
 evaluate-test = $(..)scripts/evaluate-test.sh $(test-name) $$? \
 		  $(if $(test-xfail-$(test-xfail-name)),true,false) \
+		  $(if $(stop-on-test-failure),true,false) \
 		  > $(common-objpfx)$(test-name).test-result
 
 endif # Makeconfig not yet included
diff --git a/Makefile b/Makefile
index 8214dda..e026fb1 100644
--- a/Makefile
+++ b/Makefile
@@ -324,10 +324,22 @@ tests: $(tests-special)
 	$(..)scripts/merge-test-results.sh -t $(objpfx) subdir-tests.sum \
 	  $(sort $(subdirs) .) \
 	  > $(objpfx)tests.sum
+	@grep '^ERROR:' $(objpfx)tests.sum || true
+	@grep '^FAIL:' $(objpfx)tests.sum || true
+	@echo "Summary of test results:"
+	@sed 's/:.*//' < $(objpfx)tests.sum | sort | uniq -c
+	@if grep -q '^ERROR:' $(objpfx)tests.sum; then exit 1; fi
+	@if grep -q '^FAIL:' $(objpfx)tests.sum; then exit 1; fi
 xtests:
 	$(..)scripts/merge-test-results.sh -t $(objpfx) subdir-xtests.sum \
 	  $(sort $(subdirs)) \
 	  > $(objpfx)xtests.sum
+	@grep '^ERROR:' $(objpfx)xtests.sum || true
+	@grep '^FAIL:' $(objpfx)xtests.sum || true
+	@echo "Summary of test results for extra tests:"
+	@sed 's/:.*//' < $(objpfx)xtests.sum | sort | uniq -c
+	@if grep -q '^ERROR:' $(objpfx)xtests.sum; then exit 1; fi
+	@if grep -q '^FAIL:' $(objpfx)xtests.sum; then exit 1; fi
 
 # The realclean target is just like distclean for the parent, but we want
 # the subdirs to know the difference in case they care.
diff --git a/NEWS b/NEWS
index 443b146..c69d40a 100644
--- a/NEWS
+++ b/NEWS
@@ -13,6 +13,13 @@ Version 2.20
   16611, 16613, 16623, 16632, 16639, 16642, 16670, 16674, 16677, 16683,
   16689, 16695, 16701, 16706, 16707.
 
+* Running the testsuite no longer terminates as soon as a test fails.
+  Instead, a file tests.sum (xtests.sum from "make xcheck") is generated,
+  with PASS or FAIL lines for individual tests.  A summary of the results is
+  printed, including a list of failing lists, and "make check" exits with
+  error status if there were any unexpected failures.  "make check
+  stop-on-test-failure=y" may be used to keep the old behavior.
+
 * The am33 port, which had not worked for several years, has been removed
   from ports.
 
diff --git a/manual/install.texi b/manual/install.texi
index 8562bdc..d2b8c1e 100644
--- a/manual/install.texi
+++ b/manual/install.texi
@@ -235,6 +235,12 @@ The tests (and later installation) use some pre-existing files of the
 system such as @file{/etc/passwd}, @file{/etc/nsswitch.conf} and others.
 These files must all contain correct and sensible content.
 
+Normally, @code{make check} will run all the tests before reporting
+all problems found and exiting with error status if any problems
+occurred.  You can specify @samp{stop-on-test-failure=y} when running
+@code{make check} to make the test run stop and exit with an error
+status immediately when a failure occurs.
+
 To format the @cite{GNU C Library Reference Manual} for printing, type
 @w{@code{make dvi}}.  You need a working @TeX{} installation to do
 this.  The distribution builds the on-line formatted version of the
diff --git a/scripts/evaluate-test.sh b/scripts/evaluate-test.sh
index c8f5012..2a5c156 100755
--- a/scripts/evaluate-test.sh
+++ b/scripts/evaluate-test.sh
@@ -17,12 +17,13 @@
 # License along with the GNU C Library; if not, see
 # <http://www.gnu.org/licenses/>.
 
-# usage: evaluate-test.sh test_name rc xfail
+# usage: evaluate-test.sh test_name rc xfail stop_on_failure
 
 test_name=$1
 rc=$2
 orig_rc=$rc
 xfail=$3
+stop_on_failure=$4
 
 if [ $rc -eq 0 ]; then
   result="PASS"
@@ -37,4 +38,8 @@ fi
 
 echo "$result: $test_name"
 echo "original exit status $orig_rc"
-exit $rc
+if $stop_on_failure; then
+  exit $rc
+else
+  exit 0
+fi