linux/scripts
Masahiro Yamada 205b5f80c7 kconfig: introduce m32-flag and m64-flag
[ Upstream commit 8cc4fd7350 ]

When a compiler supports multiple architectures, some compiler features
can be dependent on the target architecture.

This is typical for Clang, which supports multiple LLVM backends.
Even for GCC, we need to take care of biarch compiler cases.

It is not a problem when we evaluate cc-option in Makefiles because
cc-option is tested against the flag in question + $(KBUILD_CFLAGS).

The cc-option in Kconfig, on the other hand, does not accumulate
tested flags. Due to this simplification, it could potentially test
cc-option against a different target.

At first, Kconfig always evaluated cc-option against the host
architecture.

Since commit e8de12fb7c ("kbuild: Check for unknown options with
cc-option usage in Kconfig and clang"), in case of cross-compiling
with Clang, the target triple is correctly passed to Kconfig.

The case with biarch GCC (and native build with Clang) is still not
handled properly. We need to pass some flags to specify the target
machine bit.

Due to the design, all the macros in Kconfig are expanded in the
parse stage, where we do not know the target bit size yet.

For example, arch/x86/Kconfig allows a user to toggle CONFIG_64BIT.
If a compiler flag -foo depends on the machine bit, it must be tested
twice, one with -m32 and the other with -m64.

However, -m32/-m64 are not always recognized. So, this commits adds
m64-flag and m32-flag macros. They expand to -m32, -m64, respectively
if supported. Or, they expand to an empty string if unsupported.

The typical usage is like this:

  config FOO
          bool
          default $(cc-option,$(m64-flag) -foo) if 64BIT
          default $(cc-option,$(m32-flag) -foo)

This is clumsy, but there is no elegant way to handle this in the
current static macro expansion.

There was discussion for static functions vs dynamic functions.
The consensus was to go as far as possible with the static functions.
(https://lkml.org/lkml/2018/3/2/22)

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: George Spelvin <lkml@sdf.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-08 09:08:37 +02:00
..
atomic locking/atomics: Use sed(1) instead of non-standard head(1) option 2019-06-25 10:17:07 +02:00
basic kbuild: remove unneeded comments and code from scripts/basic/Makefile 2019-08-29 23:54:29 +09:00
coccinelle coccinelle: api/devm_platform_ioremap_resource: remove useless script 2019-10-17 09:05:56 -07:00
dtc scripts/dtc: Remove redundant YYLOC global declaration 2020-04-01 11:02:00 +02:00
gcc-plugins gcc-plugins: make it possible to disable CONFIG_GCC_PLUGINS again 2020-01-09 10:19:57 +01:00
gdb scripts/gdb: fix debugging modules compiled with hot/cold partitioning 2019-11-06 08:47:50 -08:00
genksyms genksyms: convert to SPDX License Identifier for lex.l and parse.y 2019-09-14 11:40:13 +09:00
kconfig kconfig: fix broken dependency in randconfig-generated .config 2020-02-24 08:36:32 +01:00
ksymoops
mod modpost: move the namespace field in Module.symvers last 2020-03-25 08:25:55 +01:00
package kbuild/deb-pkg: annotate libelf-dev dependency as :native 2020-01-17 19:49:07 +01:00
selinux treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
tracing treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
.gitignore scripts: remove unnecessary ihex2fw and check-lc_ctypes from .gitignore 2018-12-22 00:37:52 +09:00
adjust_autoksyms.sh kbuild: remove the first line of *.mod files 2019-07-18 02:19:31 +09:00
asn1_compiler.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36 2019-05-24 17:27:11 +02:00
bin2c.c kbuild: move bin2c back to scripts/ from scripts/basic/ 2018-07-18 01:18:05 +09:00
bloat-o-meter bloat-o-meter: ignore __addressable_ symbols 2018-12-28 12:11:44 -08:00
bootgraph.pl treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 391 2019-06-05 17:37:11 +02:00
bpf_helpers_doc.py bpf: fix script for generating man page on BPF helpers 2019-05-13 01:12:45 +02:00
cc-can-link.sh bpfilter: check compiler capability in Kconfig 2018-06-28 13:36:39 +09:00
check_extable.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
checkincludes.pl License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
checkkconfigsymbols.py treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
checkpatch.pl checkpatch: check for nested (un)?likely() calls 2019-09-25 17:51:42 -07:00
checkstack.pl scripts/checkstack.pl: Fix arm64 wrong or unknown architecture 2019-06-05 02:33:10 +09:00
checksyscalls.sh checksyscalls: fix up mq_timedreceive and stat exceptions 2019-02-19 21:27:53 +01:00
checkversion.pl License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
clang-version.sh kbuild: update comment block of scripts/clang-version.sh 2019-03-04 22:34:54 +09:00
cleanfile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cleanpatch License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
coccicheck coccicheck: return proper error code on fail 2018-08-14 08:58:56 +09:00
config License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
conmakehash.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 54 2019-05-24 17:36:42 +02:00
const_structs.checkpatch
decode_stacktrace.sh scripts/decode_stacktrace: Accept dash/underscore in modules 2019-07-12 11:05:41 -07:00
decodecode scripts/decodecode: set ARCH when running natively on arm/arm64 2018-12-28 12:11:44 -08:00
depmod.sh kbuild: modules_install: warn when missing System.map file 2018-09-09 09:14:07 +09:00
diffconfig License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
documentation-file-ref-check scripts/documentation-file-ref-check: ignore output dir 2019-06-14 14:43:01 -06:00
export_report.pl modpost: move the namespace field in Module.symvers last 2020-03-25 08:25:55 +01:00
extract_xc3028.pl treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 339 2019-06-05 17:37:07 +02:00
extract-cert.c
extract-ikconfig
extract-module-sig.pl License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
extract-sys-certs.pl License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
extract-vmlinux treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 378 2019-06-05 17:37:10 +02:00
faddr2line scripts/faddr2line: fix location of start_kernel in comment 2018-11-18 10:15:09 -08:00
file-size.sh kbuild: Use ls(1) instead of stat(1) to obtain file size 2018-03-26 02:01:24 +09:00
find-unused-docs.sh scripts/find-unused-docs: Fix massive false positives 2020-02-11 04:35:23 -08:00
gcc-goto.sh jump_label: move 'asm goto' support test to Kconfig 2019-01-06 09:46:51 +09:00
gcc-ld License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
gcc-plugin.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
gcc-version.sh kbuild: clean up scripts/gcc-version.sh 2019-03-04 22:35:04 +09:00
gcc-x86_32-has-stack-protector.sh stack-protector: test compiler capability in Kconfig and drop AUTO mode 2018-06-08 18:56:00 +09:00
gcc-x86_64-has-stack-protector.sh stack-protector: Fix test with 32-bit userland and CONFIG_64BIT=y 2018-06-25 23:21:13 +09:00
gen_compile_commands.py gen_compile_commands: lower the entry count threshold 2019-07-27 12:18:19 +09:00
gen_ksymdeps.sh kbuild: simplify dependency generation for CONFIG_TRIM_UNUSED_KSYMS 2018-12-01 23:13:14 +09:00
get_abi.pl doc: ABI scripts: add a SPDX header file 2019-06-21 16:58:37 +02:00
get_dvb_firmware treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 61 2019-05-24 17:36:45 +02:00
get_maintainer.pl get_maintainer: add ability to skip moderated mailing lists 2019-07-16 19:23:22 -07:00
gfp-translate treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
headerdep.pl License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
headers_check.pl License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
headers_install.sh kbuild: re-implement detection of CONFIG options leaked to user-space 2019-08-21 21:05:21 +09:00
insert-sys-cert.c
kallsyms.c scripts/kallsyms: fix definitely-lost memory leak 2020-01-04 19:18:23 +01:00
Kbuild.include kbuild: remove *.tmp file when filechk fails 2020-02-24 08:36:49 +01:00
Kconfig.include kconfig: introduce m32-flag and m64-flag 2020-04-08 09:08:37 +02:00
kernel-doc kernel-doc: Allow anonymous enum 2019-08-12 15:00:37 -06:00
ld-version.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
leaking_addresses.pl treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
Lindent License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
link-vmlinux.sh bpf, btf: Always output invariant hit in pahole DWARF to BTF transform 2020-02-24 08:36:55 +01:00
Makefile Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity 2019-09-27 19:37:27 -07:00
Makefile.asm-generic kbuild: force all architectures except um to include mandatory-y 2019-03-17 12:56:32 +09:00
Makefile.build kbuild: remove header compile test 2020-03-05 16:43:47 +01:00
Makefile.clean kbuild: clean up subdir-ymn calculation in Makefile.clean 2019-08-29 23:54:29 +09:00
Makefile.dtbinst DeviceTree for 4.15: 2017-11-14 18:25:40 -08:00
Makefile.extrawarn kbuild: Disable -Wpointer-to-enum-cast 2020-03-25 08:25:54 +01:00
Makefile.gcc-plugins gcc-plugins: structleak: Generalize to all variable types 2019-03-04 09:29:41 -08:00
Makefile.headersinst kbuild: move headers_check rule to usr/include/Makefile 2020-03-05 16:43:47 +01:00
Makefile.host kbuild: change *FLAGS_<basetarget>.o to take the path relative to $(obj) 2019-09-04 23:12:50 +09:00
Makefile.kasan kasan/arm64: fix CONFIG_KASAN_SW_TAGS && KASAN_INLINE 2019-08-15 13:24:04 +01:00
Makefile.kcov treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
Makefile.lib kbuild: remove header compile test 2020-03-05 16:43:47 +01:00
Makefile.modbuiltin kbuild: get rid of kernel/ prefix from in-tree modules.{order,builtin} 2019-07-17 22:39:27 +09:00
Makefile.modfinal kbuild: move modkern_{c,a}flags to Makefile.lib from Makefile.build 2019-08-22 01:14:11 +09:00
Makefile.modinst kbuild: modinst: read modules.order instead of $(MODVERDIR)/*.mod 2019-07-17 22:39:27 +09:00
Makefile.modpost Modules updates for v5.4 2019-09-22 10:34:46 -07:00
Makefile.modsign kbuild: modsign: read modules.order instead of $(MODVERDIR)/*.mod 2019-07-17 22:39:27 +09:00
Makefile.package kbuild: pkg: rename scripts/package/Makefile to scripts/Makefile.package 2019-08-25 07:42:00 +09:00
Makefile.ubsan ubsan: Remove vla bound checks. 2019-05-06 11:12:09 -07:00
makelst License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
markup_oops.pl treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 373 2019-06-05 17:37:10 +02:00
mkcompile_h Kbuild: Handle PREEMPT_RT for version string and magic 2019-08-14 01:10:42 +09:00
mkmakefile kbuild: get rid of $(realpath ...) from scripts/mkmakefile 2019-08-29 23:54:29 +09:00
mksysmap
mkuboot.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
module-common.lds
modules-check.sh kbuild: get rid of kernel/ prefix from in-tree modules.{order,builtin} 2019-07-17 22:39:27 +09:00
namespace.pl namespace: fix namespace.pl script to support relative paths 2019-10-05 15:29:49 +09:00
nsdeps scripts/nsdeps: make sure to pass all module source files to spatch 2019-11-05 14:08:29 +01:00
objdiff treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 199 2019-05-30 11:29:23 -07:00
parse-maintainers.pl parse-maintainers: Mark as executable 2020-03-25 08:25:49 +01:00
patch-kernel License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pnmtologo.c
profile2linkerlist.pl License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
prune-kernel License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
recordmcount.c ARM: 8950/1: ftrace/recordmcount: filter relocation types 2020-01-29 16:45:27 +01:00
recordmcount.h recordmcount: Fix nop_mcount() function 2019-10-12 20:49:33 -04:00
recordmcount.pl treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
setlocalversion scripts: setlocalversion: fix a bashism 2019-10-15 23:45:07 +09:00
show_delta treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 438 2019-06-05 17:37:17 +02:00
sign-file.c
sortextable.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 378 2019-06-05 17:37:10 +02:00
sortextable.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 378 2019-06-05 17:37:10 +02:00
spdxcheck-test.sh scripts: add spdxcheck.py self test 2018-12-28 12:11:44 -08:00
spdxcheck.py spdxcheck.py: fix directory structures 2019-06-01 15:51:31 -07:00
spelling.txt scripts/spelling.txt: add more spellings to spelling.txt 2019-07-12 11:05:41 -07:00
sphinx-pre-install scripts/sphinx-pre-install: seek for Noto CJK fonts for pdf output 2019-07-17 06:57:52 -03:00
split-man.pl MAINTAINERS & files: Canonize the e-mails I use at files 2018-05-04 06:21:06 -04:00
stackdelta License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
stackusage License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
subarch.include selftests: add headers_install to lib.mk 2018-09-05 08:12:09 -06:00
tags.sh kbuild: add a flag to force absolute path for srctree 2019-07-11 00:05:09 +09:00
tools-support-relr.sh scripts/tools-support-relr.sh: un-quote variables 2019-11-13 10:52:05 +00:00
unifdef.c unifdef: use memcpy instead of strncpy 2018-11-30 14:45:01 -08:00
ver_linux ver_linux: Assign constant RE to variable name for clarity 2019-01-22 13:34:35 +01:00
xen-hypercalls.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
xz_wrap.sh