When there is not enough space on your storage device, the build will
fail with 'No space left on device' error message.
The reason is obvious from the message, so you will free up some disk
space, then you will resume the build.
However, sometimes you may still see a mysterious error message:
unterminated call to function 'wildcard': missing ')'.
If you run out of the disk space, fixdep may end up with generating
incomplete .*.cmd files.
For example, if the disk-full error occurs while fixdep is running
print_dep(), the .*.cmd might be truncated like this:
$(wildcard include/config/
When you run 'make' next time, this broken .*.cmd will be included,
then Make will terminate parsing since it is a wrong syntax.
Once this happens, you need to run 'make clean' or delete the broken
.*.cmd file manually.
Even if you do not see any error message, the .*.cmd files after any
error could be potentially incomplete, and unreliable. You may miss
the re-compilation due to missing header dependency.
If printf() cannot output the string for disk shortage or whatever
reason, it returns a negative value, but currently fixdep does not
check it at all. Consequently, fixdep *successfully* generates a
broken .*.cmd file. Make never notices that since fixdep exits with 0,
which means success.
Given the intended usage of fixdep, it must respect the return value
of not only malloc(), but also printf() and putchar().
This seems a long-standing issue since the introduction of fixdep.
In old days, Kbuild tried to provide an extra safety by letting fixdep
output to a temporary file and renaming it after everything is done:
scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\
rm -f $(depfile); \
mv -f $(dot-target).tmp $(dot-target).cmd)
It was no help to avoid the current issue; fixdep successfully created
a truncated tmp file, which would be renamed to a .*.cmd file.
This problem should be fixed by propagating the error status to the
build system because:
[1] Since commit 9c2af1c737 ("kbuild: add .DELETE_ON_ERROR special
target"), Make will delete the target automatically on any failure
in the recipe.
[2] Since commit 392885ee82 ("kbuild: let fixdep directly write to
.*.cmd files"), .*.cmd file is included only when the corresponding
target already exists.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The string returned by $(filter-out ...) does not contain any leading
or trailing spaces.
With the previous commit, 'any-prereq' no longer contains any
excessive spaces.
Nor does 'cmd-check' since it expands to a $(filter-out ...) call.
So, only the space that matters is the one between 'any-prereq'
and 'cmd-check'.
By removing it from the code, we can save $(strip ...) evaluation.
This refactoring is possible because $(any-prereq)$(cmd-check) is only
passed to the first argument of $(if ...), so we are only interested
in whether or not it is empty.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The string returned by $(filter-out ...) does not contain any leading
or trailing spaces.
So, only the space that matters is the one between
$(filter-out $(PHONY),$?)
and
$(filter-out $(PHONY) $(wildcard $^),$^)
By removing it from the code, we can save $(strip ...) evaluation.
This refactoring is possible because $(any-prereq) is only passed to
the first argument of $(if ...), so we are only interested in whether
or not it is empty.
This is also the prerequisite for the next commit.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
I prefer 'cmd-check' for consistency.
We have 'echo-cmd', 'cmd', 'cmd_and_fixdep', etc. in this file.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Since commit d5470d1443 ("kbuild: re-implement Makefile.headersinst
without recursion"), headers_install emits an ugly warning.
$ make headers_install
[ snip ]
UPD include/generated/uapi/linux/version.h
find: ‘./include/uapi/Kbuild’: No such file or directory
HDRINST usr/include/video/uvesafb.h
...
This happens for GNU Make <= 4.2.1
When I wrote that commit, I missed this warning because I was using the
state-of-the-art Make version compiled from the git tree.
$(wildcard $(src)/*/) is intended to match to only existing directories
since it has a trailing slash, but actually matches to regular files too.
(include/uapi/Kbuild in this case)
This is a bug of GNU Make, and was fixed by:
| commit b7acb10e86dc8f5fdf2a2bbd87e1059c315e31d6
| Author: spagoveanu@gmail.com <spagoveanu@gmail.com>
| Date: Wed Jun 20 02:03:48 2018 +0300
|
| * src/dir.c: Preserve glob d_type field
We need to cater to old Make versions. Add '$(filter %/,...) to filter
out the regular files.
Fixes: d5470d1443 ("kbuild: re-implement Makefile.headersinst without recursion")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
__uint128_t crops up in a few files that export symbols to modules, so
teach genksyms about it and the other GCC built-in 128-bit integer types
so that we don't end up skipping the CRC generation for some symbols due
to the parser failing to spot them:
| WARNING: EXPORT symbol "kernel_neon_begin" [vmlinux] version
| generation failed, symbol will not be versioned.
| ld: arch/arm64/kernel/fpsimd.o: relocation R_AARCH64_ABS32 against
| `__crc_kernel_neon_begin' can not be used when making a shared
| object
| ld: arch/arm64/kernel/fpsimd.o:(.data+0x0): dangerous relocation:
| unsupported relocation
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
This flag turns off several other warnings that would
be useful. Most notably -warn_unused_result is disabled.
All of the following warnings are currently disabled:
UnusedValue
|-UnusedComparison
|-warn_unused_comparison
|-UnusedResult
|-warn_unused_result
|-UnevaluatedExpression
|-PotentiallyEvaluatedExpression
|-warn_side_effects_typeid
|-warn_side_effects_unevaluated_context
|-warn_unused_expr
|-warn_unused_voidptr
|-warn_unused_container_subscript_expr
|-warn_unused_call
With this flag removed there are ~10 warnings.
Patches have been submitted for each of these warnings.
Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: clang-built-linux@googlegroups.com
Link: https://github.com/ClangBuiltLinux/linux/issues/520
Signed-off-by: Nathan Huckleberry <nhuck@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
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 <jani.nikula@intel.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
It is absolutely fine to add extra sanity checks in package scripts,
but it is not necessary to do so.
This is already covered by the daily compile-testing (0day bot etc.)
because headers_check is run as a part of the normal build process
when CONFIG_HEADERS_CHECK=y.
Replace it with the newly-added "make headers".
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Now that headers_install.sh is invoked per file, remove the for-loop
in the shell script.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Now that hdr-inst is used only in the top Makefile, move it there
from scripts/Kbuild.include.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Since commit fcc8487d47 ("uapi: export all headers under uapi
directories"), the headers in uapi directories are all exported by
default although exceptional cases are still allowed by the syntax
'no-export-headers'.
The traditional directory descending has been kept (in a somewhat
hacky way), but it is actually unneeded.
Get rid of it to simplify the code.
Also, handle files one by one instead of the previous per-directory
processing. This will emit much more log, but I like it.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
In Linux build system, build targets and installation targets are
separated.
Examples are:
- 'make vmlinux' -> 'make install'
- 'make modules' -> 'make modules_install'
- 'make dtbs' -> 'make dtbs_install'
- 'make vdso' -> 'make vdso_install'
The intention is to run the build targets under the normal privilege,
then the installation targets under the root privilege since we need
the write permission to the system directories.
We have 'make headers_install' but the corresponding 'make headers'
stage does not exist. The purpose of headers_install is to provide
the kernel interface to C library. So, nobody would try to install
headers to /usr/include directly.
If 'sudo make INSTALL_HDR_PATH=/usr/include headers_install' were run,
some build artifacts in the kernel tree would be owned by root because
some of uapi headers are generated by 'uapi-asm-generic', 'archheaders'
targets.
Anyway, I believe it makes sense to split the header installation into
two stages.
[1] 'make headers'
Process headers in uapi directories by scripts/headers_install.sh
and copy them to usr/include
[2] 'make headers_install'
Copy '*.h' verbatim from usr/include to $(INSTALL_HDR_PATH)/include
For the backward compatibility, 'headers_install' depends on 'headers'.
Some samples expect uapi headers in usr/include. So, the 'headers'
target is useful to build up them in the fixed location usr/include
irrespective of INSTALL_HDR_PATH.
Another benefit is to stop polluting the final destination with the
time-stamp files '.install' and '.check'. Maybe you can see them in
your toolchains.
Lastly, my main motivation is to prepare for compile-testing uapi
headers. To build something, we have to save an object and .*.cmd
somewhere. The usr/include/ will be the work directory for that.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Since commit 2aedcd098a ("kbuild: suppress annoying "... is up to date."
message"), if_changed and friends nicely suppress "is up to date" messages.
We do not need per-Makefile tricks.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
headers_install_all does not make much sense any more because different
architectures export different set of uapi/linux/ headers. As you see
in include/uapi/linux/Kbuild, the installation of a.out.h, kvm.h, and
kvm_para.h is arch-dependent. So, headers_install_all repeats the
installation/removal of them.
If somebody really thinks it is useful to do headers_install for all
architectures, it would be possible by small shell-scripting, but
the top Makefile does not have to provide entry targets just for that
purpose.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
It makes little sense to pass -Waggregate-return these days since large
part of the linux kernel rely on returning struct(s). For instance:
../include/linux/timekeeping.h: In function 'show_uptime':
../include/linux/ktime.h:91:34: error: function call has aggregate value [-Werror=aggregate-return]
#define ktime_to_timespec64(kt) ns_to_timespec64((kt))
^~~~~~~~~~~~~~~~~~~~~~
../include/linux/timekeeping.h:166:8: note: in expansion of macro 'ktime_to_timespec64'
*ts = ktime_to_timespec64(ktime_get_coarse_boottime());
Remove this warning from W=2 completely.
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Pull yet more SPDX updates from Greg KH:
"Another round of SPDX header file fixes for 5.2-rc4
These are all more "GPL-2.0-or-later" or "GPL-2.0-only" tags being
added, based on the text in the files. We are slowly chipping away at
the 700+ different ways people tried to write the license text. All of
these were reviewed on the spdx mailing list by a number of different
people.
We now have over 60% of the kernel files covered with SPDX tags:
$ ./scripts/spdxcheck.py -v 2>&1 | grep Files
Files checked: 64533
Files with SPDX: 40392
Files with errors: 0
I think the majority of the "easy" fixups are now done, it's now the
start of the longer-tail of crazy variants to wade through"
* tag 'spdx-5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (159 commits)
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 450
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 449
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 448
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 446
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 445
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 444
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 443
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 442
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 440
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 438
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 437
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 436
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 435
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 434
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 433
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 432
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 431
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 430
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 429
...
To print the pathname that will be used by shell in the current
environment, 'command -v' is a standardized way. [1]
'which' is also often used in scripts, but it is less portable.
When I worked on commit bd55f96fa9 ("kbuild: refactor cc-cross-prefix
implementation"), I was eager to use 'command -v' but it did not work.
(The reason is explained below.)
I kept 'which' as before but got rid of '> /dev/null 2>&1' as I
thought it was no longer needed. Sorry, I was wrong.
It works well on my Ubuntu machine, but Alexey Brodkin reports noisy
warnings on CentOS7 when 'which' fails to find the given command in
the PATH environment.
$ which foo
which: no foo in (/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin)
Given that behavior of 'which' depends on system (and it may not be
installed by default), I want to try 'command -v' once again.
The specification [1] clearly describes the behavior of 'command -v'
when the given command is not found:
Otherwise, no output shall be written and the exit status shall reflect
that the name was not found.
However, we need a little magic to use 'command -v' from Make.
$(shell ...) passes the argument to a subshell for execution, and
returns the standard output of the command.
Here is a trick. GNU Make may optimize this by executing the command
directly instead of forking a subshell, if no shell special characters
are found in the command and omitting the subshell will not change the
behavior.
In this case, no shell special character is used. So, Make will try
to run it directly. However, 'command' is a shell-builtin command,
then Make would fail to find it in the PATH environment:
$ make ARCH=m68k defconfig
make: command: Command not found
make: command: Command not found
make: command: Command not found
In fact, Make has a table of shell-builtin commands because it must
ask the shell to execute them.
Until recently, 'command' was missing in the table.
This issue was fixed by the following commit:
| commit 1af314465e5dfe3e8baa839a32a72e83c04f26ef
| Author: Paul Smith <psmith@gnu.org>
| Date: Sun Nov 12 18:10:28 2017 -0500
|
| * job.c: Add "command" as a known shell built-in.
|
| This is not a POSIX shell built-in but it's common in UNIX shells.
| Reported by Nick Bowler <nbowler@draconx.ca>.
Because the latest release is GNU Make 4.2.1 in 2016, this commit is
not included in any released versions. (But some distributions may
have back-ported it.)
We need to trick Make to spawn a subshell. There are various ways to
do so:
1) Use a shell special character '~' as dummy
$(shell : ~; command -v $(c)gcc)
2) Use a variable reference that always expands to the empty string
(suggested by David Laight)
$(shell command$${x:+} -v $(c)gcc)
3) Use redirect
$(shell command -v $(c)gcc 2>/dev/null)
I chose 3) to not confuse people. The stderr would not be polluted
anyway, but it will provide extra safety, and is easy to understand.
Tested on Make 3.81, 3.82, 4.0, 4.1, 4.2, 4.2.1
[1] http://pubs.opengroup.org/onlinepubs/9699919799/utilities/command.html
Fixes: bd55f96fa9 ("kbuild: refactor cc-cross-prefix implementation")
Cc: linux-stable <stable@vger.kernel.org> # 5.1
Reported-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Alexey Brodkin <abrodkin@synopsys.com>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation version 2 of the license
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 315 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531190115.503150771@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Based on 1 normalized pattern(s):
this program file is free software you can redistribute it and or
modify it under the terms of the gnu general public license as
published by the free software foundation version 2 of the license
this program is distributed in the hope that it will be useful but
without any warranty without even the implied warranty of
merchantability or fitness for a particular purpose see the gnu
general public license for more details you should have received a
copy of the gnu general public license along with this program in a
file named copying if not write to the free software foundation inc
51 franklin street fifth floor boston ma 02110 1301 usa
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 1 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531081038.017566012@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Based on 1 normalized pattern(s):
this program file is free software you can redistribute it and or
modify it under the terms of the gnu general public license as
published by the free software foundation version 2 of the license
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 1 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531081036.527324761@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
