linux/scripts
Masahiro Yamada f8f69dc0b4 kconfig: make unmet dependency warnings readable
Currently, the unmet dependency warnings end up with endlessly long
expressions, most of which are false positives.

Here is test code to demonstrate how it currently works.

[Test Case]

  config DEP1
          def_bool y

  config DEP2
          bool "DEP2"

  config A
          bool "A"
          select E

  config B
          bool "B"
          depends on DEP2
          select E

  config C
          bool "C"
          depends on DEP1 && DEP2
          select E

  config D
          def_bool n
          select E

  config E
          bool
          depends on DEP1 && DEP2

[Result]

  $ make config
  scripts/kconfig/conf  --oldaskconfig Kconfig
  *
  * Linux Kernel Configuration
  *
  DEP2 (DEP2) [N/y/?] (NEW) n
  A (A) [N/y/?] (NEW) y
  warning: (A && B && D) selects E which has unmet direct
  dependencies (DEP1 && DEP2)

Here, I see some points to be improved.

First, '(A || B || D)' would make more sense than '(A && B && D)'.
I am not sure if this is intentional, but expr_simplify_unmet_dep()
turns OR expressions into AND, like follows:

        case E_OR:
                return expr_alloc_and(

Second, we see false positives.  'A' is a real unmet dependency.
'B' is false positive because 'DEP1' is fixed to 'y', and 'B' depends
on 'DEP2'.  'C' was correctly dropped by expr_simplify_unmet_dep().
'D' is also false positive because it has no chance to be enabled.
Current expr_simplify_unmet_dep() cannot avoid those false positives.

After all, I decided to use the same helpers as used for printing
reverse dependencies in the help.

With this commit, unreadable warnings (most of the reported symbols are
false positives) in the real world:

$ make ARCH=score allyesconfig
scripts/kconfig/conf  --allyesconfig Kconfig
warning: (HWSPINLOCK_QCOM && AHCI_MTK && STMMAC_PLATFORM &&
 DWMAC_IPQ806X && DWMAC_LPC18XX && DWMAC_OXNAS && DWMAC_ROCKCHIP &&
 DWMAC_SOCFPGA && DWMAC_STI && TI_CPSW && PINCTRL_GEMINI &&
 PINCTRL_OXNAS && PINCTRL_ROCKCHIP && PINCTRL_DOVE &&
 PINCTRL_ARMADA_37XX && PINCTRL_STM32 && S3C2410_WATCHDOG &&
 VIDEO_OMAP3 && VIDEO_S5P_FIMC && USB_XHCI_MTK && RTC_DRV_AT91SAM9 &&
 LPC18XX_DMAMUX && VIDEO_OMAP4 && COMMON_CLK_GEMINI &&
 COMMON_CLK_ASPEED && COMMON_CLK_NXP && COMMON_CLK_OXNAS &&
 COMMON_CLK_BOSTON && QCOM_ADSP_PIL && QCOM_Q6V5_PIL && QCOM_GSBI &&
 ATMEL_EBI && ST_IRQCHIP && RESET_IMX7 && PHY_HI6220_USB &&
 PHY_RALINK_USB && PHY_ROCKCHIP_PCIE && PHY_DA8XX_USB) selects
 MFD_SYSCON which has unmet direct dependencies (HAS_IOMEM)
warning: (PINCTRL_AT91 && PINCTRL_AT91PIO4 && PINCTRL_OXNAS &&
 PINCTRL_PISTACHIO && PINCTRL_PIC32 && PINCTRL_MESON &&
 PINCTRL_NOMADIK && PINCTRL_MTK && PINCTRL_MT7622 && GPIO_TB10X)
 selects OF_GPIO which has unmet direct dependencies (GPIOLIB && OF &&
 HAS_IOMEM)
warning: (FAULT_INJECTION_STACKTRACE_FILTER && LATENCYTOP && LOCKDEP)
 selects FRAME_POINTER which has unmet direct dependencies
 (DEBUG_KERNEL && (CRIS || M68K || FRV || UML || SUPERH || BLACKFIN ||
 MN10300 || METAG) || ARCH_WANT_FRAME_POINTERS)

will be turned into:

$ make ARCH=score allyesconfig
scripts/kconfig/conf  --allyesconfig Kconfig

WARNING: unmet direct dependencies detected for MFD_SYSCON
  Depends on [n]: HAS_IOMEM [=n]
  Selected by [y]:
  - PINCTRL_STM32 [=y] && PINCTRL [=y] && (ARCH_STM32 ||
 COMPILE_TEST [=y]) && OF [=y]
  - RTC_DRV_AT91SAM9 [=y] && RTC_CLASS [=y] && (ARCH_AT91 ||
 COMPILE_TEST [=y])
  - RESET_IMX7 [=y] && RESET_CONTROLLER [=y]
  - PHY_HI6220_USB [=y] && (ARCH_HISI && ARM64 ||
 COMPILE_TEST [=y])
  - PHY_RALINK_USB [=y] && (RALINK || COMPILE_TEST [=y])
  - PHY_ROCKCHIP_PCIE [=y] && (ARCH_ROCKCHIP && OF [=y] ||
 COMPILE_TEST [=y])

WARNING: unmet direct dependencies detected for OF_GPIO
  Depends on [n]: GPIOLIB [=y] && OF [=y] && HAS_IOMEM [=n]
  Selected by [y]:
  - PINCTRL_MTK [=y] && PINCTRL [=y] && (ARCH_MEDIATEK ||
 COMPILE_TEST [=y]) && OF [=y]
  - PINCTRL_MT7622 [=y] && PINCTRL [=y] && (ARCH_MEDIATEK ||
 COMPILE_TEST [=y]) && OF [=y] && (ARM64 || COMPILE_TEST [=y])

WARNING: unmet direct dependencies detected for FRAME_POINTER
  Depends on [n]: DEBUG_KERNEL [=y] && (CRIS || M68K || FRV || UML ||
 SUPERH || BLACKFIN || MN10300 || METAG) || ARCH_WANT_FRAME_POINTERS [=n]
  Selected by [y]:
  - LATENCYTOP [=y] && DEBUG_KERNEL [=y] && STACKTRACE_SUPPORT [=y] &&
 PROC_FS [=y] && !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM_UNWIND &&
 !ARC && !X86

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Petr Vorel <petr.vorel@gmail.com>
2018-03-26 02:04:06 +09:00
..
basic fixdep: do not ignore kconfig.h 2018-03-05 23:48:29 +09:00
coccinelle Coccinelle: memdup: Fix typo in warning messages 2018-03-03 00:41:24 +09:00
dtc DeviceTree for 4.15: 2017-11-14 18:25:40 -08:00
gcc-plugins gcc-plugins: Use dynamic initializers 2018-02-05 17:27:46 -08:00
gdb scripts/gdb/linux/tasks.py: fix get_thread_info 2018-01-19 10:09:41 -08:00
genksyms genksyms: drop *.hash.c from .gitignore 2018-01-13 21:50:13 +09:00
kconfig kconfig: make unmet dependency warnings readable 2018-03-26 02:04:06 +09:00
ksymoops Fix dead URLs to ftp.kernel.org 2017-03-28 16:16:52 +02:00
mod Modules updates for v4.16 2018-02-07 14:29:34 -08:00
package kbuild: pkg: make out-of-tree rpm/deb-pkg build immediately fail 2017-12-13 00:07:00 +09:00
selinux Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
tracing License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
.gitignore Docs: clean up some DocBook loose ends 2017-06-23 14:17:38 -06:00
adjust_autoksyms.sh kbuild: fix scripts/adjust_autoksyms.sh* for the no modules case 2016-12-11 22:30:10 +01:00
asn1_compiler.c ASN.1: fix open failure check on headername 2016-04-06 14:06:48 +01:00
bloat-o-meter scripts/bloat-o-meter: fix typos in help 2018-03-09 01:12:31 +09:00
bootgraph.pl scripts: Switch to more portable Perl shebang 2017-05-14 11:20:44 +09:00
check_00index.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
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 checkkconfigsymbols.py: support Kconfig's 'imply' statement 2017-02-03 11:49:06 +01:00
checkpatch.pl checkpatch: kconfig: prefer 'help' over '---help---' 2018-03-26 02:03:57 +09:00
checkstack.pl License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
checksyscalls.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +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
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 Coccinelle: coccicheck: fix typo 2018-02-02 00:21:47 +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
const_structs.checkpatch const_structs.checkpatch: add frequently used from Julia Lawall's list 2016-10-11 15:06:30 -07:00
decode_stacktrace.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
decodecode scripts/decodecode: make it take multiline Code line 2018-01-31 17:18:34 -08:00
depmod.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
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 Documentation: add script and build target to check for broken file references 2017-10-12 11:07:42 -06:00
export_report.pl scripts: Switch to more portable Perl shebang 2017-05-14 11:20:44 +09:00
extract_xc3028.pl scripts: Switch to more portable Perl shebang 2017-05-14 11:20:44 +09:00
extract-cert.c KEYS: Remove unnecessary header #inclusions from extract-cert.c 2015-09-25 16:31:45 +01:00
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
faddr2line scripts/faddr2line: fix CROSS_COMPILE unset error 2017-12-14 16:00:48 -08:00
find-unused-docs.sh scripts: Add a script to find unused documentation 2017-10-23 08:01:37 -06:00
gcc-goto.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
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 License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
gcc-x86_32-has-stack-protector.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
gcc-x86_64-has-stack-protector.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
gen_initramfs_list.sh Kbuild misc updates for 4.13 2017-07-07 15:09:09 -07:00
get_dvb_firmware scripts: Switch to more portable Perl shebang 2017-05-14 11:20:44 +09:00
get_maintainer.pl get_maintainer: add more --self-test options 2017-11-17 16:10:01 -08:00
gfp-translate
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 Merge branch 'linus' into locking/core, to resolve conflicts 2017-11-07 10:32:44 +01:00
headers.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
insert-sys-cert.c KEYS: Reserve an extra certificate symbol for inserting without recompiling 2016-02-26 15:30:20 +00:00
kallsyms.c kbuild/kallsyms: trivial typo fix 2018-03-02 09:20:56 +09:00
Kbuild.include kbuild: create directory for make cache only when necessary 2017-11-16 09:07:32 +09:00
kernel-doc scripts: kernel_doc: better handle show warnings logic 2018-01-01 12:49:07 -07:00
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 leaking_addresses: add SigIgn to false positives 2017-11-14 09:29:27 +11:00
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 kbuild: drop superfluous GCC_PLUGINS_CFLAGS assignment 2018-03-02 09:20:56 +09:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Makefile.asm-generic Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Makefile.build objtool, retpolines: Integrate objtool with retpoline support more closely 2018-02-21 16:54:32 +01:00
Makefile.clean License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Makefile.dtbinst DeviceTree for 4.15: 2017-11-14 18:25:40 -08:00
Makefile.extrawarn Kbuild: suppress packed-not-aligned warning for default setting only 2018-01-18 09:37:53 +09:00
Makefile.gcc-plugins License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Makefile.headersinst Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Makefile.host Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Makefile.kasan kasan: rework Kconfig settings 2018-02-06 18:32:47 -08:00
Makefile.kcov Makefile: support flag -fsanitizer-coverage=trace-cmp 2017-11-17 16:10:04 -08:00
Makefile.lib kbuild: Handle builtin dtb file names containing hyphens 2018-03-09 01:14:38 +09:00
Makefile.modbuiltin License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Makefile.modinst License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Makefile.modpost Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Makefile.modsign License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Makefile.ubsan lib/ubsan: remove returns-nonnull-attribute checks 2018-02-06 18:32:46 -08:00
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 scripts: Switch to more portable Perl shebang 2017-05-14 11:20:44 +09:00
mkcompile_h Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
mkmakefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mksysmap mksysmap: Add h8300 local symbol pattern 2015-06-23 13:35:47 +09:00
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 module: set .init_array alignment to 8 2017-03-13 09:40:28 -07:00
namespace.pl scripts: Switch to more portable Perl shebang 2017-05-14 11:20:44 +09:00
objdiff scripts: objdiff: Ignore debug info when comparing 2017-03-11 11:13:38 +09:00
parse-maintainers.pl parse-maintainers: add ability to specify filenames 2017-11-17 16:10:01 -08:00
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 ftrace: Allow for function tracing to record init functions on boot up 2017-03-24 20:51:49 -04:00
recordmcount.h recordmcount: Fix endianness handling bug for nop_mcount 2015-11-03 10:45:26 -05:00
recordmcount.pl scripts: Switch to more portable Perl shebang 2017-05-14 11:20:44 +09:00
setlocalversion License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
show_delta
sign-file.c sign-file: fix build error in sign-file.c with libressl 2017-02-10 12:43:47 +11:00
sortextable.c powerpc: Build-time sort the exception table 2016-11-14 11:11:51 +11:00
sortextable.h
spelling.txt spelling.txt: add "unnecessary" typo variants 2017-11-17 16:10:00 -08:00
sphinx-pre-install docs-rst: don't require adjustbox anymore 2017-09-08 10:02:55 -06:00
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
tags.sh scripts/tags.sh: change find_other_sources() for include directories 2018-01-31 17:18:34 -08:00
unifdef.c
ver_linux License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +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