Add test that MAP_* constants agree with kernel.

Continuing the process of building up and using Python infrastructure
for extracting and using values in headers, this patch adds a test
that MAP_* constants from sys/mman.h agree with those in the Linux
kernel headers.  (Other sys/mman.h constants could be added to the
test separately.)

This set of constants has grown over time, so the generic code is
enhanced to allow saying extra constants are OK on either side of the
comparison (where the caller sets those parameters based on the Linux
kernel headers version, compared with the version the headers were
last updated from).  Although the test is a custom Python file, my
intention is to move in future to a single Python script for such
tests and text files it takes as inputs, once there are enough
examples to provide a guide to the common cases in such tests (I'd
like to end up with most or all such sets of constants copied from
kernel headers having such tests, and likewise for structure layouts
from the kernel).

The Makefile code is essentially the same as for tst-signal-numbers,
but I didn't try to find an object file to depend on to represent the
dependency on the headers used by the test (the conform/ tests don't
try to represent such header dependencies at all, for example).

Tested with build-many-glibcs.py, and also for x86_64 with older
kernel headers.

	* scripts/glibcextract.py (compare_macro_consts): Take parameters
	to allow extra macros from first or second sources.
	* sysdeps/unix/sysv/linux/tst-mman-consts.py: New file.
	* sysdeps/unix/sysv/linux/Makefile [$(subdir) = misc]
	(tests-special): Add $(objpfx)tst-mman-consts.out.
	($(objpfx)tst-mman-consts.out): New makefile target.

1 files changed, 9 insertions, 0 deletions

diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile
index 2c1a7dd274..f8274552a7 100644
--- a/sysdeps/unix/sysv/linux/Makefile
+++ b/sysdeps/unix/sysv/linux/Makefile
@@ -100,6 +100,15 @@ $(objpfx)tst-sysconf-iov_max: $(objpfx)tst-sysconf-iov_max-uapi.o
 
 $(objpfx)tst-pkey: $(shared-thread-library)
 
+tests-special += $(objpfx)tst-mman-consts.out
+$(objpfx)tst-mman-consts.out: ../sysdeps/unix/sysv/linux/tst-mman-consts.py
+	PYTHONPATH=../scripts \
+	$(PYTHON) ../sysdeps/unix/sysv/linux/tst-mman-consts.py \
+		   --cc="$(CC) $(patsubst -DMODULE_NAME=%, \
+					  -DMODULE_NAME=testsuite, \
+					  $(CPPFLAGS))" \
+	< /dev/null > $@ 2>&1; $(evaluate-test)
+
 endif # $(subdir) == misc
 
 ifeq ($(subdir),time)