tests-mcheck: New variable to run tests with MALLOC_CHECK_=3

This new variable allows various subsystems in glibc to run all or
some of their tests with MALLOC_CHECK_=3.  This patch adds
infrastructure support for this variable as well as an implementation
in malloc/Makefile to allow running some of the tests with
MALLOC_CHECK_=3.

At present some tests in malloc/ have been excluded from the mcheck
tests either because they're specifically testing MALLOC_CHECK_ or
they are failing in master even without the Memory Tagging patches
that prompted this work.  Some tests were reviewed and found to need
specific error points that MALLOC_CHECK_ defeats by terminating early
but a thorough review of all tests is needed to bring them into mcheck
coverage.

The following failures are seen in current master:

FAIL: malloc/tst-malloc-fork-deadlock-mcheck
FAIL: malloc/tst-malloc-stats-cancellation-mcheck
FAIL: malloc/tst-malloc-thread-fail-mcheck
FAIL: malloc/tst-realloc-mcheck
FAIL: malloc/tst-reallocarray-mcheck

All of these are due to the Memory Tagging patchset and will be fixed
separately.

Rules

@@ -155,6 +155,7 @@ xtests: tests $(xtests-special)
 else
 tests: $(tests:%=$(objpfx)%.out) $(tests-internal:%=$(objpfx)%.out) \
        $(tests-container:%=$(objpfx)%.out) \
+       $(tests-mcheck:%=$(objpfx)%-mcheck.out) \
        $(tests-special) $(tests-printers-out)
 xtests: tests $(xtests:%=$(objpfx)%.out) $(xtests-special)
 endif
@@ -165,7 +166,7 @@ ifeq ($(run-built-tests),no)
 tests-expected =
 else
 tests-expected = $(tests) $(tests-internal) $(tests-printers) \
-	$(tests-container)
+	$(tests-container) $(tests-mcheck:%=%-mcheck)
 endif
 tests:
 	$(..)scripts/merge-test-results.sh -s $(objpfx) $(subdir) \
@@ -191,6 +192,7 @@ else
 binaries-pie-tests =
 binaries-pie-notests =
 endif
+binaries-mcheck-tests = $(tests-mcheck:%=%-mcheck)
 else
 binaries-all-notests =
 binaries-all-tests = $(tests) $(tests-internal) $(xtests) $(test-srcs)
@@ -200,6 +202,7 @@ binaries-static-tests =
 binaries-static =
 binaries-pie-tests =
 binaries-pie-notests =
+binaries-mcheck-tests =
 endif
 
 binaries-pie = $(binaries-pie-tests) $(binaries-pie-notests)
@@ -223,6 +226,14 @@ $(addprefix $(objpfx),$(binaries-shared-tests)): %: %.o \
 	$(+link-tests)
 endif
 
+ifneq "$(strip $(binaries-mcheck-tests))" ""
+$(addprefix $(objpfx),$(binaries-mcheck-tests)): %-mcheck: %.o \
+  $(link-extra-libs-tests) \
+  $(sort $(filter $(common-objpfx)lib%,$(link-libc))) \
+  $(addprefix $(csu-objpfx),start.o) $(+preinit) $(+postinit)
+	$(+link-tests)
+endif
+
 ifneq "$(strip $(binaries-pie-tests))" ""
 $(addprefix $(objpfx),$(binaries-pie-tests)): %: %.o \
   $(link-extra-libs-tests) \
@@ -253,6 +264,12 @@ $(addprefix $(objpfx),$(binaries-static-tests)): %: %.o \
 	$(+link-static-tests)
 endif
 
+# All mcheck tests will be run with MALLOC_CHECK_=3
+define mcheck-ENVS
+$(1)-mcheck-ENV = MALLOC_CHECK_=3
+endef
+$(foreach t,$(tests-mcheck),$(eval $(call mcheck-ENVS,$(t))))
+
 ifneq "$(strip $(tests) $(tests-internal) $(xtests) $(test-srcs))" ""
 # These are the implicit rules for making test outputs
 # from the test programs and whatever input files are present.

malloc/Makefile

@@ -62,6 +62,16 @@ endif
 tests += $(tests-static)
 test-srcs = tst-mtrace
 
+# These tests either are run with MALLOC_CHECK_=3 by default or do not work
+# with MALLOC_CHECK_=3 because they expect a specific failure.
+tests-exclude-mcheck = tst-mcheck tst-malloc-usable \
+	tst-interpose-nothread tst-interpose-static-nothread \
+	tst-interpose-static-thread tst-malloc-too-large \
+	tst-mxfast tst-safe-linking
+
+# Run all tests with MALLOC_CHECK_=3
+tests-mcheck = $(filter-out $(tests-exclude-mcheck),$(tests))
+
 routines = malloc morecore mcheck mtrace obstack reallocarray \
   scratch_buffer_grow scratch_buffer_grow_preserve \
   scratch_buffer_set_array_size \
@@ -100,6 +110,11 @@ $(objpfx)tst-malloc-thread-exit: $(shared-thread-library)
 $(objpfx)tst-malloc-thread-fail: $(shared-thread-library)
 $(objpfx)tst-malloc-fork-deadlock: $(shared-thread-library)
 $(objpfx)tst-malloc-stats-cancellation: $(shared-thread-library)
+$(objpfx)tst-malloc-backtrace-mcheck: $(shared-thread-library)
+$(objpfx)tst-malloc-thread-exit-mcheck: $(shared-thread-library)
+$(objpfx)tst-malloc-thread-fail-mcheck: $(shared-thread-library)
+$(objpfx)tst-malloc-fork-deadlock-mcheck: $(shared-thread-library)
+$(objpfx)tst-malloc-stats-cancellation-mcheck: $(shared-thread-library)
 
 # Export the __malloc_initialize_hook variable to libc.so.
 LDFLAGS-tst-mallocstate = -rdynamic
@@ -239,6 +254,8 @@ $(tests:%=$(objpfx)%.o): CPPFLAGS += -DTEST_NO_MALLOPT
 $(objpfx)tst-interpose-nothread: $(objpfx)tst-interpose-aux-nothread.o
 $(objpfx)tst-interpose-thread: \
   $(objpfx)tst-interpose-aux-thread.o $(shared-thread-library)
+$(objpfx)tst-interpose-thread-mcheck: \
+  $(objpfx)tst-interpose-aux-thread.o $(shared-thread-library)
 $(objpfx)tst-interpose-static-nothread: $(objpfx)tst-interpose-aux-nothread.o
 $(objpfx)tst-interpose-static-thread: \
   $(objpfx)tst-interpose-aux-thread.o $(static-thread-library)
@@ -256,3 +273,6 @@ $(objpfx)tst-dynarray-fail-mem.out: $(objpfx)tst-dynarray-fail.out
 $(objpfx)tst-malloc-tcache-leak: $(shared-thread-library)
 $(objpfx)tst-malloc_info: $(shared-thread-library)
 $(objpfx)tst-mallocfork2: $(shared-thread-library)
+$(objpfx)tst-malloc-tcache-leak-mcheck: $(shared-thread-library)
+$(objpfx)tst-malloc_info-mcheck: $(shared-thread-library)
+$(objpfx)tst-mallocfork2-mcheck: $(shared-thread-library)