Commit Graph

36 Commits

Author SHA1 Message Date
Masahiro Yamada 9ad86d747c kconfig: remove unreachable printf()
Remove the unreachable code detected by clang.

  $ make HOSTCC=clang HOSTCFLAGS=-Wunreachable-code defconfig
    [ snip ]
  scripts/kconfig/expr.c:1134:2: warning: code will never be executed [-Wunreachable-code]
          printf("[%dgt%d?]", t1, t2);
          ^~~~~~
  1 warning generated.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-12-28 16:22:47 +09:00
Thomas Hebb 3460d0bc25 kconfig: distinguish between dependencies and visibility in help text
Kconfig makes a distinction between dependencies (defined by "depends
on" expressions and enclosing "if" blocks) and visibility (which
includes all dependencies, but also includes inline "if" expressions of
individual properties as well as, for prompts, "visible if" expressions
of enclosing menus).

Before commit bcdedcc1af ("menuconfig: print more info for symbol
without prompts"), the "Depends on" lines of a symbol's help text
indicated the visibility of the prompt property they appeared under.
After bcdedcc1af, there was always only a single "Depends on" line,
which indicated the visibility of the first P_SYMBOL property of the
symbol. Since P_SYMBOLs never have inline if expressions, this was in
effect the same as the dependencies of the menu item that the P_SYMBOL
was attached to.

Neither of these situations accurately conveyed the dependencies of a
symbol--the first because it was actually the visibility, and the second
because it only showed the dependencies from a single definition.

With this series, we are back to printing separate dependencies for each
definition, but we print the actual dependencies (rather than the
visibility) in the "Depends on" line. However, it can still be useful to
know the visibility of a prompt, so this patch adds a "Visible if" line
that shows the visibility only if the visibility is different from the
dependencies (which it isn't for most prompts in Linux).

Before:

  Symbol: THUMB2_KERNEL [=n]
  Type  : bool
  Defined at arch/arm/Kconfig:1417
    Prompt: Compile the kernel in Thumb-2 mode
    Depends on: (CPU_V7 [=y] || CPU_V7M [=n]) && !CPU_V6 [=n] && !CPU_V6K [=n]
    Location:
      -> Kernel Features
    Selects: ARM_UNWIND [=n]

After:

   Symbol: THUMB2_KERNEL [=n]
   Type  : bool
   Defined at arch/arm/Kconfig:1417
     Prompt: Compile the kernel in Thumb-2 mode
     Depends on: (CPU_V7 [=y] || CPU_V7M [=n]) && !CPU_V6 [=n] && !CPU_V6K [=n]
     Visible if: (CPU_V7 [=y] || CPU_V7M [=n]) && !CPU_V6 [=n] && !CPU_V6K [=n] && !CPU_THUMBONLY [=n]
     Location:
       -> Kernel Features
     Selects: ARM_UNWIND [=n]

Signed-off-by: Thomas Hebb <tommyhebb@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-01-07 02:18:45 +09:00
Thomas Hebb 272a721030 kconfig: don't crash on NULL expressions in expr_eq()
NULL expressions are taken to always be true, as implemented by the
expr_is_yes() macro and by several other functions in expr.c. As such,
they ought to be valid inputs to expr_eq(), which compares two
expressions.

Signed-off-by: Thomas Hebb <tommyhebb@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2019-12-17 19:21:07 +09:00
Masahiro Yamada 558e78e3ce kconfig: split some C files out of zconf.y
I want to compile each C file independently instead of including all
of them from zconf.y.

Split out confdata.c, expr.c, symbol.c, and preprocess.c .
These are low-hanging fruits.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-28 22:22:38 +09:00
Masahiro Yamada 0c87410010 kconfig: convert to SPDX License Identifier
All files in lxdialog/ are licensed under GPL-2.0+, and the rest are
under GPL-2.0. I added GPL-2.0 tags to test scripts in tests/.

Documentation/process/license-rules.rst does not suggest anything
about the flex/bison files. Because flex does not accept the C++
comment style at the very top of a file, I used the C style for
zconf.l, and so for zconf.y for consistency.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-28 22:22:28 +09:00
Masahiro Yamada 0cbe3ac439 kconfig: remove k_invalid from expr_parse_string() return type
The only possibility of k_invalid being returned was when
expr_parse_sting() parsed S_OTHER type symbol. This actually never
happened, and this is even clearer since S_OTHER has gone.

Clean up unreachable code.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-08 10:42:42 +09:00
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
Eugeniu Rosca d9119b5925 kconfig: Print reverse dependencies in groups
Surprisingly or not, disabling a CONFIG option (which is assumed to
be unneeded) may be not so trivial. Especially it is not trivial, when
this CONFIG option is selected by a dozen of other configs. Before the
moment commit 1ccb271433 ("kconfig: make "Selected by:" and
"Implied by:" readable") popped up in v4.16-rc1, it was an absolute pain
to break down the "Selected by" reverse dependency expression in order
to identify all those configs which select (IOW *do not allow
disabling*) a certain feature (assumed to be not needed).

This patch tries to make one step further by putting at users'
fingertips the revdep top level OR sub-expressions grouped/clustered by
the tristate value they evaluate to. This should allow the users to
directly concentrate on and tackle the _active_ reverse dependencies.

To give some numbers and quantify the complexity of certain reverse
dependencies, assuming commit 617aebe6a9 ("Merge tag
'usercopy-v4.16-rc1' of
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux"), ARCH=arm64
and vanilla arm64 defconfig, here is the top 10 CONFIG options with
the highest amount of top level "||" sub-expressions/tokens that make
up the final "Selected by" reverse dependency expression.

| Config            | All revdep | Active revdep |
|-------------------|------------|---------------|
| REGMAP_I2C        | 212        | 9             |
| CRC32             | 167        | 25            |
| FW_LOADER         | 128        | 5             |
| MFD_CORE          | 124        | 9             |
| FB_CFB_IMAGEBLIT  | 114        | 2             |
| FB_CFB_COPYAREA   | 111        | 2             |
| FB_CFB_FILLRECT   | 110        | 2             |
| SND_PCM           | 103        | 2             |
| CRYPTO_HASH       | 87         | 19            |
| WATCHDOG_CORE     | 86         | 6             |

The story behind the above is that users need to visually
review/evaluate 212 expressions which *potentially* select REGMAP_I2C
in order to identify the expressions which *actually* select REGMAP_I2C,
for a particular ARCH and for a particular defconfig used.

To make this experience smoother, change the way reverse dependencies
are displayed to the user from [1] to [2].

[1] Old representation of DMA_ENGINE_RAID:
  Selected by:
  - AMCC_PPC440SPE_ADMA [=n] && DMADEVICES [=y] && (440SPe || 440SP)
  - BCM_SBA_RAID [=m] && DMADEVICES [=y] && (ARM64 [=y] || ...
  - FSL_RAID [=n] && DMADEVICES [=y] && FSL_SOC && ...
  - INTEL_IOATDMA [=n] && DMADEVICES [=y] && PCI [=y] && X86_64
  - MV_XOR [=n] && DMADEVICES [=y] && (PLAT_ORION || ARCH_MVEBU [=y] ...
  - MV_XOR_V2 [=y] && DMADEVICES [=y] && ARM64 [=y]
  - XGENE_DMA [=n] && DMADEVICES [=y] && (ARCH_XGENE [=y] || ...
  - DMATEST [=n] && DMADEVICES [=y] && DMA_ENGINE [=y]

[2] New representation of DMA_ENGINE_RAID:
  Selected by [y]:
  - MV_XOR_V2 [=y] && DMADEVICES [=y] && ARM64 [=y]
  Selected by [m]:
  - BCM_SBA_RAID [=m] && DMADEVICES [=y] && (ARM64 [=y] || ...
  Selected by [n]:
  - AMCC_PPC440SPE_ADMA [=n] && DMADEVICES [=y] && (440SPe || ...
  - FSL_RAID [=n] && DMADEVICES [=y] && FSL_SOC && ...
  - INTEL_IOATDMA [=n] && DMADEVICES [=y] && PCI [=y] && X86_64
  - MV_XOR [=n] && DMADEVICES [=y] && (PLAT_ORION || ARCH_MVEBU [=y] ...
  - XGENE_DMA [=n] && DMADEVICES [=y] && (ARCH_XGENE [=y] || ...
  - DMATEST [=n] && DMADEVICES [=y] && DMA_ENGINE [=y]

Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Reviewed-by: Petr Vorel <pvorel@suse.cz>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:03:58 +09:00
Masahiro Yamada 9a47ceec54 kconfig: clean-up reverse dependency help implementation
This commit splits out the special E_OR handling ('-' instead of '||')
into a dedicated helper expr_print_revdev().

Restore the original expr_print() prior to commit 1ccb271433
("kconfig: make "Selected by:" and "Implied by:" readable").

This makes sense because:

  - We need to chop those expressions only when printing the reverse
    dependency, and only when E_OR is encountered

  - Otherwise, it should be printed as before, so fall back to
    expr_print()

This also improves the behavior; for a single line, it was previously
displayed in the same line as "Selected by", like this:

  Selected by: A [=n] && B [=n]

This will be displayed in a new line, consistently:

  Selected by:
  - A [=n] && B [=n]

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Petr Vorel <pvorel@suse.cz>
2018-03-26 02:03:57 +09:00
Masahiro Yamada 9e3e10c725 kconfig: send error messages to stderr
These messages should be directed to stderr.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-02-09 04:10:10 +09:00
Linus Torvalds 562f36ed28 Kconfig updates for v4.16
A pretty big batch of Kconfig updates. I have to mention the lexer
 and parser of Kconfig are now built from real .l and .y sources.
 So, flex and bison are the requirement for building the kernel.
 Both of them (unlike gperf) have been stable for a long time. This
 change has been tested several weeks in linux-next, and I did not
 receive any problem report about this.
 
 Summary:
 
 - Add checks for mistakes, like the choice default is not in
   choice, help is doubled
 
 - Document data structure and complex code
 
 - Fix various memory leaks
 
 - Change Makefile to build lexer and parser instead of using
   pre-generated C files
 
 - Drop 'boolean' keyword, which is equivalent to 'bool'
 
 - Use default 'yy' prefix and remove unneeded Make variables
 
 - Fix gettext() check for xconfig
 
 - Announce that oldnoconfig will be finally removed
 
 - Make 'Selected by:' and 'Implied by' readable in help and
   search result
 
 - Hide silentoldconfig from 'make help' to stop confusing people
 
 - Fix misc things and cleanups
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Merge tag 'kconfig-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kconfig updates from Masahiro Yamada:
 "A pretty big batch of Kconfig updates.

  I have to mention the lexer and parser of Kconfig are now built from
  real .l and .y sources. So, flex and bison are the requirement for
  building the kernel. Both of them (unlike gperf) have been stable for
  a long time. This change has been tested several weeks in linux-next,
  and I did not receive any problem report about this.

  Summary:

   - add checks for mistakes, like the choice default is not in choice,
     help is doubled

   - document data structure and complex code

   - fix various memory leaks

   - change Makefile to build lexer and parser instead of using
     pre-generated C files

   - drop 'boolean' keyword, which is equivalent to 'bool'

   - use default 'yy' prefix and remove unneeded Make variables

   - fix gettext() check for xconfig

   - announce that oldnoconfig will be finally removed

   - make 'Selected by:' and 'Implied by' readable in help and search
     result

   - hide silentoldconfig from 'make help' to stop confusing people

   - fix misc things and cleanups"

* tag 'kconfig-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (37 commits)
  kconfig: Remove silentoldconfig from help and docs; fix kconfig/conf's help
  kconfig: make "Selected by:" and "Implied by:" readable
  kconfig: announce removal of oldnoconfig if used
  kconfig: fix make xconfig when gettext is missing
  kconfig: Clarify menu and 'if' dependency propagation
  kconfig: Document 'if' flattening logic
  kconfig: Clarify choice dependency propagation
  kconfig: Document SYMBOL_OPTIONAL logic
  kbuild: remove unnecessary LEX_PREFIX and YACC_PREFIX
  kconfig: use default 'yy' prefix for lexer and parser
  kconfig: make conf_unsaved a local variable of conf_read()
  kconfig: make xfgets() really static
  kconfig: make input_mode static
  kconfig: Warn if there is more than one help text
  kconfig: drop 'boolean' keyword
  kconfig: use bool instead of boolean for type definition attributes, again
  kconfig: Remove menu_end_entry()
  kconfig: Document important expression functions
  kconfig: Document automatic submenu creation code
  kconfig: Fix choice symbol expression leak
  ...
2018-02-01 11:45:49 -08:00
Petr Vorel 1ccb271433 kconfig: make "Selected by:" and "Implied by:" readable
Reverse dependency expressions can get rather unwieldy, especially if
a symbol is selected by more than a handful of other symbols. I.e. it's
possible to have near endless expressions like:
   A && B && !C || D || F && (G || H) || [...]

Chop these expressions into actually readable chunks:
   - A && B && !C
   - D
   - F && (G || H)
   - [...]

I.e. transform the top level OR tokens into newlines and prepend each
line with a minus. This makes the "Selected by:" and "Implied by:" blurb
much easier to read. This is done only if there is more than one top
level OR. "Depends on:" and "Range :" were deliberately left as they are.

Based on idea from Paul Bolle.

Suggested-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Petr Vorel <petr.vorel@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-25 21:53:00 +09:00
Ulf Magnusson 0735f7e5de kconfig: Document important expression functions
Many of these functions are quite the head scratchers if you don't know
what they're trying to do. Document them.

Also make it clear which functions rewrite expressions in-place and
which return new expressions. This prevents memory errors.

No functional changes. Only comments added.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 00:49:28 +09:00
Ulf Magnusson 5b1374b3b3 kconfig: Fix expr_free() E_NOT leak
Only the E_NOT operand and not the E_NOT node itself was freed, due to
accidentally returning too early in expr_free(). Outline of leak:

	switch (e->type) {
	...
	case E_NOT:
		expr_free(e->left.expr);
		return;
	...
	}
	*Never reached, 'e' leaked*
	free(e);

Fix by changing the 'return' to a 'break'.

Summary from Valgrind on 'menuconfig' (ARCH=x86) before the fix:

	LEAK SUMMARY:
	   definitely lost: 44,448 bytes in 1,852 blocks
	   ...

Summary after the fix:

	LEAK SUMMARY:
	   definitely lost: 1,608 bytes in 67 blocks
	   ...

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 00:49:27 +09:00
Nicolas Pitre 9059a3493e kconfig: fix relational operators for bool and tristate symbols
Since commit 31847b67be ("kconfig: allow use of relations other than
(in)equality") it is possible to use relational operators in Kconfig
statements. However, those operators give unexpected results when
applied to bool/tristate values:

	(n < y) = y (correct)
	(m < y) = y (correct)
	(n < m) = n (wrong)

This happens because relational operators process bool and tristate
symbols as strings and m sorts before n. It makes little sense to do a
lexicographical compare on bool and tristate values though.

Documentation/kbuild/kconfig-language.txt states that expression can have
a value of 'n', 'm' or 'y' (or 0, 1, 2 respectively for calculations).
Let's make it so for relational comparisons with bool/tristate
expressions as well and document them. If at least one symbol is an
actual string then the lexicographical compare works just as before.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-06 02:31:23 +09:00
Michal Sojka f6aad2615c kconfig: Fix copy&paste error
Fixes: 31847b67be ("kconfig: allow use of relations other than (in)equality")
Signed-off-by: Michal Sojka <sojkam1@fel.cvut.cz>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2015-10-20 19:13:14 +02:00
Jan Beulich 31847b67be kconfig: allow use of relations other than (in)equality
Over the years I found it desirable to be able to use all sorts of
relations, not just (in)equality. And apparently I'm not the only one,
as there's at least one example in the tree where the programmer
assumed this would work (see DEBUG_UART_8250_WORD in
arch/arm/Kconfig.debug). Another possible use would e.g. be to fold the
two SMP/NR_CPUS prompts into one: SMP could be promptless, simply
depending on NR_CPUS > 1.

A (desirable) side effect of this change - resulting from numeric
values now necessarily being compared as numbers rather than as
strings - is that comparing hex values now works as expected: Other
than int ones (which aren't allowed to have leading zeroes), zeroes
following the 0x prefix made them compare unequal even if their values
were equal.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2015-06-15 14:05:58 +02:00
Martin Walch e911503085 Kconfig: Remove bad inference rules expr_eliminate_dups2()
expr_eliminate_dups2() in scripts/kconfig/expr.c applies two invalid
inference rules:

(FOO || BAR) && (!FOO && !BAR) -> n
(FOO && BAR) || (!FOO || !BAR) -> y

They would be correct in propositional logic, but this is a three-valued
logic, and here it is wrong in that it changes semantics. It becomes
immediately visible when assigning the value 1 to both, FOO and BAR:

(FOO || BAR) && (!FOO && !BAR)
-> min(max(1, 1), min(2-1, 2-1)) = min(1, 1) = 1

while n evaluates to 0 and

(FOO && BAR) || (!FOO || !BAR)
-> max(min(1, 1), max(2-1, 2-1)) = max(1, 1) = 1

with y evaluating to 2.

Fix it by removing expr_eliminate_dups2() and the functions that have no
use anywhere else: expr_extract_eq_and(), expr_extract_eq_or(),
and expr_extract_eq() from scripts/kconfig/expr.c

Currently the bug is not triggered in mainline, so this patch does not
modify the configuration space there. To observe the bug consider this
example:

config MODULES
        def_bool y
        option modules

config FOO
        def_tristate m

config BAR
        def_tristate m

config TEST1
        def_tristate y
        depends on (FOO || BAR) && (!FOO && !BAR)

if TEST1 = n
comment "TEST1 broken"
endif

config TEST2
        def_tristate y
        depends on (FOO && BAR) || (!FOO || !BAR)

if TEST2 = y
comment "TEST2 broken"
endif

config TEST3
        def_tristate y
        depends on m && !m

if TEST3 = n
comment "TEST3 broken"
endif

TEST1, TEST2 and TEST3 should all evaluate to m, but without the patch,
none of them does. It is probably not obvious that TEST3 is the same bug,
but it becomes clear when considering what happens internally to the
expression
m && !m":
First it expands to
(m && MODULES) && !(m && MODULES),
then it is transformed into
(m && MODULES) && (!m || !MODULES),
and finally due to the bug it is replaced with n.

As a side effect, this patch reduces code size in expr.c by roughly 10%
and slightly improves startup time for all configuration frontends.

Signed-off-by: Martin Walch <walch.martin@web.de>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2015-05-25 16:04:12 +08:00
Michal Marek ad8d40cda3 kconfig: Remove unnecessary prototypes from headers
Signed-off-by: Michal Marek <mmarek@suse.cz>
2015-02-25 15:00:17 +01:00
Michal Marek 463157444e kconfig: Remove dead code
Signed-off-by: Michal Marek <mmarek@suse.cz>
2015-02-25 15:00:16 +01:00
Alan Cox 177acf7846 kconfig: Fix malloc handling in conf tools
(and get them out of the noise in the audit work)

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-11-20 12:12:47 +01:00
Arnaud Lacombe 8494453ad5 kconfig: use calloc() for expr allocation
Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
2011-07-02 01:04:37 -04:00
Arnaud Lacombe 5a6f8d2bd9 kconfig: nuke LKC_DIRECT_LINK cruft
This interface is not (and has never been ?) used by any frontend, just get rid
of it.

Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
2011-06-06 15:32:20 -04:00
Michal Marek 17742dc743 kconfig: Make expr_copy() take a const argument
Fixes
scripts/kconfig/expr.c: In function ‘expr_get_leftmost_symbol’:
scripts/kconfig/expr.c:1026:2: warning: passing argument 1 of ‘expr_copy’ discards qualifiers from pointer target type
scripts/kconfig/expr.c:67:14: note: expected ‘struct expr *’ but argument is of type ‘const struct expr *’

Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-12-21 17:59:16 +01:00
Arnaud Lacombe 1137c56b74 kconfig: simplify select-with-unmet-direct-dependency warning
This is an attempt to simplify the expressing printed by kconfig when a
symbol is selected but still has direct unmet dependency.

First, the symbol reverse dependency is split in sub-expression. Then,
each sub-expression is checked to ensure that it does not contains the
unmet dependency. This removes the false-positive symbols and fixed symbol
which already have the correct dependency. Finally, only the symbol
responsible of the "select" is printed, instead of its full dependency tree.

CC: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-12-21 17:59:14 +01:00
Jean Sacren bf5e327a30 kconfig: Fix warning: ignoring return value of 'fwrite'
This fix facilitates fwrite() in both confdata.c and expr.c, either it
succeeds in writing, or an error occurs, or the end of file is reached.

Signed-off-by: Jean Sacren <sakiwit@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-08-13 00:40:26 +02:00
Li Zefan 70ed074718 kconfig: print the range of integer/hex symbol in help text
Without this patch, one has to refer to the Kconfig file to find
out the range of an integer/hex symbol.

  │ Symbol: NR_CPUS [=4]
  │ Type  : integer
  │ Range : [2 8]
  │ Prompt: Maximum number of CPUs
  │   Defined at arch/x86/Kconfig:761
  │   Depends on: SMP [=y] && !MAXSMP [=n]
  │   Location:
  │     -> Processor type and features

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-06-02 15:10:32 +02:00
Vadim Bendebury (вб) da60fbbcb6 menuconfig: wrap long help lines
Help text for certain config options is very extensive (the text
includes the names of all  other options the option in question depends
on). Long lines are not wrapped, making it impossible to see the list
without scrolling horizontally.

This patch adds some logic which wraps help screen lines at word
boundaries to prevent truncating.

Tested by running

  ARCH=powerpc make menuconfig O=/tmp/build

which shows that the long lines are now wrapped, and

 ARCH=powerpc make xconfig O=/tmp/build

to demonstrate that it still compiles and operates as expected.

Signed-off-by: Vadim Bendebury <vbendeb@google.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-02-02 14:33:55 +01:00
Trevor Keith 4356f48907 kbuild: add static to prototypes
Warnings found via gcc -Wmissing-prototypes.

Signed-off-by: Trevor Keith <tsrk@tsrk.net>
Acked-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-09-20 12:27:44 +02:00
Cheng Renquan 544e433a9e kconfig: add symbol value to help find the real depend
Sometimes when configuring need to disable some unused item, but the item is
selected by many other items, it's hard to find the real dependency which
selected it, This patch add every symbol's value accompanied to make it
possible to find the real dependency easily.

An example is CONFIG_RFKILL,

  ---------------------- RF switch subsystem support ----------------------
  | CONFIG_RFKILL:                                                        |
  |                                                                       |
  | Say Y here if you want to have control over RF switches               |
  | found on many WiFi and Bluetooth cards.                               |
  |                                                                       |
  | To compile this driver as a module, choose M here: the                |
  | module will be called rfkill.                                         |
  |                                                                       |
  | Symbol: RFKILL [=m]                                                   |
  | Prompt: RF switch subsystem support                                   |
  |   Defined at net/rfkill/Kconfig:4                                     |
  |   Depends on: NET [=y]                                                |
  |   Location:                                                           |
  |     -> Networking support (NET [=y])                                  |
  |   Selected by: IWLCORE [=n] && NETDEVICES [=y] && !S390 [=S390] && PC |
  |                                                                       |
  ----------------------------------------------------------------( 99%)---

Signed-off-by: Cheng Renquan <crquan@gmail.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-09-20 12:27:41 +02:00
Jan Beulich f5eaa323eb kconfig: tristate choices with mixed tristate and boolean values
Change kconfig behavior so that mixing bool and tristate config
settings in a choice is possible and has the desired effect of offering
just the tristate options individually if the choice gets set to M, and
a normal boolean selection if the choice gets set to Y.

Also fix scripts/kconfig/conf's handling of children of choice values -
there may be more than one immediate child, and all of them need to be
processed.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: "Roman Zippel" <zippel@linux-m68k.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-01-28 23:21:18 +01:00
Roman Zippel 7a96292335 kconfig: explicitly introduce expression list
Rename E_CHOICE to E_LIST to explicitly add support for expression
lists. Add a helper macro expr_list_for_each_sym to more easily iterate
over the list.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-01-28 23:14:39 +01:00
Sam Ravnborg d6ee35764f kconfig: rename E_OR & friends to avoid name clash
We had macros named the same as a set of enumeration values.
It is legal code but very confusing to read - so rename
the macros from E_* to EXPR_*

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
2008-01-28 23:14:38 +01:00
Roman Zippel ab45d190fd kconfig: create links in info window
Extend the expression print helper function to allow customization of the
symbol output and use it to add links to the info window.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-06-09 16:28:07 +02:00
Roman Zippel c0e150acde kconfig: remove SYMBOL_{YES,MOD,NO}
The SYMBOL_{YES,MOD,NO} are not really used anymore (they were more used be
the cml1 converter), so just remove them.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-06-09 07:31:30 +02:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00