Add parameter to allow enabling/disabling selftests via configure

This is a follow-up of:

  https://sourceware.org/ml/gdb-patches/2018-08/msg00347.html

Instead of going throttle and always enabling our selftests (even in
non-development builds), this patch is a bit more conservative and
introduces a configure option ("--enable-unit-tests") that allows the
user to choose whether she wants unit tests in the build or not.  Note
that the current behaviour is retained: if no option is provided, GDB
will have selftests included in a development build, and will *not*
have selftests included in a non-development build.

The rationale for having this option is still the same: due to the
many racy testcases and random failures we see when running the GDB
testsuite, it is unfortunately not possible to perform a full test
when one is building a downstream package.  As the Fedora GDB
maintainer and one of the Debian GDB uploaders, I feel like this
situation could be improved by, at least, executing our selftests
after the package has been built.

This patch introduces no regressions to our build.

OK?

gdb/ChangeLog:
2018-10-10  Sergio Durigan Junior  <sergiodj@redhat.com>
	    Simon Marchi <simark@simark.ca>

	* README (`configure' options): Add documentation for new
	"--enable-unit-tests" option.
	* acinclude.m4: Include "selftest.m4".
	* configure: Regenerate.
	* configure.ac: Use "GDB_AC_SELFTEST".
	* maint.c (maintenance_selftest): Update message informing
	that selftests have been disabled.
	(maintenance_info_selftests): Likewise.
	* selftest.m4: New file.

gdb/gdbserver/ChangeLog:
2018-10-10  Sergio Durigan Junior  <sergiodj@redhat.com>
	    Simon Marchi <simark@simark.ca>

	* acinclude.m4: Include "../selftest.m4".
	* configure: Regenerate.
	* configure.ac: Use "GDB_AC_SELFTEST".
	* configure.srv: Use "$enable_unittests" instead of
	"$development" when checking whether unit tests have been
	enabled.
	* server.c (captured_main): Update message informing that
	selftests have been disabled.

gdb/testsuite/ChangeLog:
2018-10-10  Sergio Durigan Junior  <sergiodj@redhat.com>

	* gdb.gdb/unittest.exp: Update expected message informing that
	selftests have been disabled.
	* gdb.server/unittest.exp: Likewise.

squash! Add parameter to allow enabling/disabling selftests via configure

1 files changed, 26 insertions, 1 deletions

diff --git a/gdb/configure b/gdb/configure
index adb26e5..3652455 100755
--- a/gdb/configure
+++ b/gdb/configure
@@ -896,6 +896,7 @@ enable_sim
 enable_gdbserver
 with_babeltrace
 with_libbabeltrace_prefix
+enable_unit_tests
 '
       ac_precious_vars='build_alias
 host_alias
@@ -1561,6 +1562,8 @@ Optional Features:
   --enable-sim            link gdb with simulator
   --enable-gdbserver      automatically build gdbserver (yes/no/auto, default
                           is auto)
+  --enable-unit-tests     Enable the inclusion of unit tests when compiling
+                          GDB
 
 Optional Packages:
   --with-PACKAGE[=ARG]    use PACKAGE [ARG=yes]
@@ -17838,15 +17841,37 @@ ac_config_links="$ac_config_links $ac_config_links_1"
 $as_echo "#define GDB_DEFAULT_HOST_CHARSET \"UTF-8\"" >>confdefs.h
 
 
-if $development; then
+
+# Check whether we will enable the inclusion of unit tests when
+# compiling GDB.
+#
+# The default value of this option changes depending whether we're on
+# development mode (in which case it's "true") or not (in which case
+# it's "false").
+# Check whether --enable-unit-tests was given.
+if test "${enable_unit_tests+set}" = set; then :
+  enableval=$enable_unit_tests; case "${enableval}" in
+  yes)  enable_unittests=true  ;;
+  no)   enable_unittests=false ;;
+  *)    as_fn_error $? "bad value ${enableval} for --{enable,disable}-unit-tests option" "$LINENO" 5 ;;
+esac
+else
+  enable_unittests=$development
+fi
+
+
+if $enable_unittests; then
 
 $as_echo "#define GDB_SELF_TEST 1" >>confdefs.h
 
+
   CONFIG_OBS="$CONFIG_OBS \$(SUBDIR_UNITTESTS_OBS) common/selftest.o selftest-arch.o"
   CONFIG_SRCS="$CONFIG_SRCS \$(SUBDIR_UNITTESTS_SRCS) common/selftest.c selftest-arch.c"
+
 fi
 
 
+
   gdb_ac_transform=`echo "$program_transform_name" | sed -e 's/\\$\\$/\\$/g'`
   GDB_TRANSFORM_NAME=`echo gdb | sed -e "$gdb_ac_transform"`
   if test "x$GDB_TRANSFORM_NAME" = x; then