linux/lib/kunit
Masahiro Yamada 15d5761ad3 kbuild: introduce ccflags-remove-y and asflags-remove-y
CFLAGS_REMOVE_<file>.o filters out flags when compiling a particular
object, but there is no convenient way to do that for every object in
a directory.

Add ccflags-remove-y and asflags-remove-y to make it easily.

Use ccflags-remove-y to clean up some Makefiles.

The add/remove order works as follows:

 [1] KBUILD_CFLAGS specifies compiler flags used globally

 [2] ccflags-y adds compiler flags for all objects in the
     current Makefile

 [3] ccflags-remove-y removes compiler flags for all objects in the
     current Makefile (New feature)

 [4] CFLAGS_<file> adds compiler flags per file.

 [5] CFLAGS_REMOVE_<file> removes compiler flags per file.

Having [3] before [4] allows us to remove flags from most (but not all)
objects in the current Makefile.

For example, kernel/trace/Makefile removes $(CC_FLAGS_FTRACE)
from all objects in the directory, then adds it back to
trace_selftest_dynamic.o and CFLAGS_trace_kprobe_selftest.o

The same applies to lib/livepatch/Makefile.

Please note ccflags-remove-y has no effect to the sub-directories.
In contrast, the previous notation got rid of compiler flags also from
all the sub-directories.

The following are not affected because they have no sub-directories:

  arch/arm/boot/compressed/
  arch/powerpc/xmon/
  arch/sh/
  kernel/trace/

However, lib/ has several sub-directories.

To keep the behavior, I added ccflags-remove-y to all Makefiles
in subdirectories of lib/, except the following:

  lib/vdso/Makefile        - Kbuild does not descend into this Makefile
  lib/raid/test/Makefile   - This is not used for the kernel build

I think commit 2464a609de ("ftrace: do not trace library functions")
excluded too much. In the next commit, I will remove ccflags-remove-y
from the sub-directories of lib/.

Suggested-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Brendan Higgins <brendanhiggins@google.com> (KUnit)
Tested-by: Anders Roxell <anders.roxell@linaro.org>
2020-08-10 01:32:59 +09:00
..
assert.c kunit: subtests should be indented 4 spaces according to TAP 2020-03-26 14:08:41 -06:00
debugfs.c kunit: add debugfs /sys/kernel/debug/kunit/<suite>/results display 2020-03-26 14:07:18 -06:00
debugfs.h kunit: add debugfs /sys/kernel/debug/kunit/<suite>/results display 2020-03-26 14:07:18 -06:00
Kconfig kunit: default KUNIT_* fragments to KUNIT_ALL_TESTS 2020-06-01 14:23:25 -06:00
kunit-example-test.c kunit: allow kunit tests to be loaded as a module 2020-01-09 16:42:29 -07:00
kunit-test.c kunit: add log test 2020-03-26 14:08:01 -06:00
Makefile kbuild: introduce ccflags-remove-y and asflags-remove-y 2020-08-10 01:32:59 +09:00
string-stream-test.c kunit: allow kunit tests to be loaded as a module 2020-01-09 16:42:29 -07:00
string-stream.c kunit: move string-stream.h to lib/kunit 2020-01-09 16:41:05 -07:00
string-stream.h kunit: move string-stream.h to lib/kunit 2020-01-09 16:41:05 -07:00
test.c kunit: Add missing newline in summary message 2020-04-23 15:42:00 -06:00
try-catch-impl.h kunit: hide unexported try-catch interface in try-catch-impl.h 2020-01-09 16:42:09 -07:00
try-catch.c kunit: remove timeout dependence on sysctl_hung_task_timeout_seconds 2020-01-09 16:42:55 -07:00