user/sven/linux.git/scripts/Makefile.lib, branch v5.3.1

kbuild: remove unused single-used-m

2019-07-27T03:18:19Z

This is unused since commit 9f69a496f100 ("kbuild: split out *.mod out of {single,multi}-used-m rules"). Signed-off-by: Masahiro Yamada

kbuild: compile-test headers listed in header-test-m as well

2019-07-17T13:37:51Z

It will be useful to control the header-test by a tristate option. If CONFIG_FOO is a tristate option, you can write like this: header-test-$(CONFIG_FOO) += foo.h Signed-off-by: Masahiro Yamada

kbuild: fix compression errors getting ignored

2019-07-10T15:05:09Z

A missing compression utility or other errors were not picked up by make and an empty kernel image was produced. By removing the &&, errors will no longer be ignored. Signed-off-by: Harald Seiler Signed-off-by: Masahiro Yamada

kbuild: replace KBUILD_SRCTREE with boolean building_out_of_srctree

2019-07-10T15:05:09Z

Commit 25b146c5b8ce ("kbuild: allow Kbuild to start from any directory") deprecated KBUILD_SRCTREE. It is only used in tools/testing/selftest/ to distinguish out-of-tree build. Replace it with a new boolean flag, building_out_of_srctree. I also replaced the conditional ($(srctree),.) because the next commit will allow an absolute path to be used for $(srctree) even when building in the source tree. Signed-off-by: Masahiro Yamada

kbuild: support header-test-pattern-y

2019-07-09T01:10:52Z

In my view, most of headers can be self-contained. So, it would be tedious to add every header to header-test-y explicitly. We usually end up with "all headers with some exceptions". There are two types in exceptions: [1] headers that are never compiled as standalone units For examples, include/linux/compiler-gcc.h is not intended for direct inclusion. We should always exclude such ones. [2] headers that are conditionally compiled as standalone units Some headers can be compiled only for particular architectures. For example, include/linux/arm-cci.h can be compiled only for arm/arm64 because it requires to exist. Clang can compile include/soc/nps/mtm.h only for arc because it contains an arch-specific register in inline assembler. So, you can write Makefile like this: header-test- += linux/compiler-gcc.h header-test-$(CONFIG_ARM) += linux/arm-cci.h header-test-$(CONFIG_ARM64) += linux/arm-cci.h header-test-$(CONFIG_ARC) += soc/nps/mtm.h The new syntax header-test-pattern-y will be useful to specify "the rest". The typical usage is like this: header-test-pattern-y += */*.h This will add all the headers in sub-directories to the test coverage, excluding $(header-test-). In this regards, header-test-pattern-y behaves like a weaker variant of header-test-y. Caveat: The patterns in header-test-pattern-y are prefixed with $(srctree)/$(src)/ but not $(objtree)/$(obj)/. Stale generated headers are often left over when you traverse the git history without cleaning. Wildcard patterns for $(objtree) may match to stale headers, which could fail to compile. One pitfall is $(srctree)/$(src)/ and $(objtree)/$(obj)/ point to the same directory for in-tree building. So, header-test-pattern-y should be used with care since it can potentially match to stale headers. Caveat2: You could use wildcard for header-test-. For example, header-test- += asm-generic/% ... will exclude headers in asm-generic directory. Unfortunately, the wildcard character is '%' instead of '*' here because this is evaluated by $(filter-out ...) whereas header-test-pattern-y is evaluated by $(wildcard ...). This is a kludge, but seems useful in some places... Signed-off-by: Masahiro Yamada Tested-by: Jani Nikula

kbuild: do not create wrappers for header-test-y

2019-07-09T01:10:27Z

header-test-y does not work with headers in sub-directories. For example, you may want to write a Makefile, like this: include/linux/Kbuild: header-test-y += mtd/nand.h This entry will create a wrapper include/linux/mtd/nand.hdrtest.c with the following content: #include "mtd/nand.h" To make this work, we need to add $(srctree)/include/linux to the header search path. It would be tedious to add ccflags-y. Instead, we could change the *.hdrtest.c rule to wrap: #include "nand.h" This works for in-tree build since #include "..." searches in the relative path from the header with this directive. For O=... build, we need to add $(srctree)/include/linux/mtd to the header search path, which will be even more tedious. After all, I thought it would be handier to compile headers directly without creating wrappers. I added a new build rule to compile %.h into %.h.s The target is %.h.s instead of %.h.o because it is slightly faster. Also, as for GCC, an empty assembly is smaller than an empty object. I wrote the build rule: $(CC) $(c_flags) -S -o $@ -x c /dev/null -include $< instead of: $(CC) $(c_flags) -S -o $@ -x c $< Both work fine with GCC, but the latter is bad for Clang. This comes down to the difference in the -Wunused-function policy. GCC does not warn about unused 'static inline' functions at all. Clang does not warn about the ones in included headers, but does about the ones in the source. So, we should handle headers as headers, not as source files. In fact, this has been hidden since commit abb2ea7dfd82 ("compiler, clang: suppress warning for unused static inline functions"), but we should not rely on that. Signed-off-by: Masahiro Yamada Acked-by: Jani Nikula Tested-by: Jani Nikula

kbuild: add support for ensuring headers are self-contained

2019-06-15T10:57:02Z

Sometimes it's useful to be able to explicitly ensure certain headers remain self-contained, i.e. that they are compilable as standalone units, by including and/or forward declaring everything they depend on. Add special target header-test-y where individual Makefiles can add headers to be tested if CONFIG_HEADER_TEST is enabled. This will generate a dummy C file per header that gets built as part of extra-y. Signed-off-by: Jani Nikula Reviewed-by: Sam Ravnborg Signed-off-by: Masahiro Yamada

dt-bindings: Pass binding directory to validation tools

2019-05-22T14:01:01Z

In order to have $ref's to schema files within the kernel, we need to pass the base path of bindings to the schema validation tools. Cc: Masahiro Yamada Cc: Michal Marek Cc: devicetree@vger.kernel.org Cc: linux-kbuild@vger.kernel.org Signed-off-by: Rob Herring

kbuild: remove 'addtree' and 'flags' magic for header search paths

2019-05-18T02:49:57Z

The 'addtree' and 'flags' in scripts/Kbuild.include are so compilecated and ugly. As I mentioned in [1], Kbuild should stop automatic prefixing of header search path options. I fixed up (almost) all Makefiles in the kernel. Now 'addtree' and 'flags' have been removed. Kbuild still caters to add $(srctree)/$(src) and $(objtree)/$(obj) to the header search path for O= building, but never touches extra compiler options from ccflags-y etc. [1]: https://patchwork.kernel.org/patch/9632347/ Signed-off-by: Masahiro Yamada

kbuild: use $(srctree) instead of KBUILD_SRC to check out-of-tree build

2019-04-02T14:28:04Z

KBUILD_SRC was conventionally used for some different purposes: [1] To remember the source tree path [2] As a flag to check if sub-make is already done [3] As a flag to check if Kbuild runs out of tree For [1], we do not need to remember it because the top Makefile can compute it by $(realpath $(dir $(lastword $(MAKEFILE_LIST)))) [2] has been replaced with self-commenting 'sub_make_done'. For [3], we can distinguish in-tree/out-of-tree by comparing $(srctree) and '.' This commit converts [3] to prepare for the KBUILD_SRC removal. Signed-off-by: Masahiro Yamada