Hi Masahiro, Thanks for constantly improving the user experience of Kconfig. Just one small remark below. On Tue, Mar 06, 2018 at 07:51:39PM +0900, Masahiro Yamada wrote: > 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 > def_bool n > > 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 allyesconfig > scripts/kconfig/conf --allyesconfig Kconfig > 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 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 && DWMA > C_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 && LP > C18XX_DMAMUX && VIDEO_OMAP4 && COMMON_CLK_GEMINI && COMMON_CLK_ASPEED && C > OMMON_CLK_NXP && COMMON_CLK_OXNAS && COMMON_CLK_BOSTON && ATMEL_ST && QCOM > _ADSP_PIL && QCOM_Q6V5_PIL && QCOM_GSBI && ATMEL_EBI && ST_IRQCHIP && RESE > T_IMX7 && PHY_HI6220_USB && PHY_RALINK_USB && PHY_ROCKCHIP_PCIE && PHY_DA8 > XX_USB) selects MFD_SYSCON which has unmet direct dependencies (HAS_IOMEM) > warning: (PINCTRL_AT91 && PINCTRL_AT91PIO4 && PINCTRL_OXNAS && PINCTRL_PIS > TACHIO && PINCTRL_PIC32 && PINCTRL_MESON && PINCTRL_NOMADIK && PINCTRL_MTK > && PINCTRL_MT7622 && GPIO_TB10X) selects OF_GPIO which has unmet direct d > ependencies (GPIOLIB && OF && HAS_IOMEM) > warning: (FAULT_INJECTION_STACKTRACE_FILTER && LATENCYTOP && LOCKDEP) sele > cts FRAME_POINTER which has unmet direct dependencies (DEBUG_KERNEL && (CR > IS || M68K || FRV || UML || SUPERH || BLACKFIN || MN10300 || METAG) || ARC > H_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: > 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]) > - ATMEL_ST [=y] && GENERIC_CLOCKEVENTS [=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: > 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: > 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@xxxxxxxxxxxxx> > --- > > Changes in v2: > - update test case > > scripts/kconfig/expr.c | 29 ----------------------------- > scripts/kconfig/expr.h | 1 - > scripts/kconfig/symbol.c | 33 +++++++++++++++++++++------------ > 3 files changed, 21 insertions(+), 42 deletions(-) > > diff --git a/scripts/kconfig/expr.c b/scripts/kconfig/expr.c > index 49376e1..235e179 100644 > --- a/scripts/kconfig/expr.c > +++ b/scripts/kconfig/expr.c > @@ -1150,35 +1150,6 @@ expr_get_leftmost_symbol(const struct expr *e) > return expr_copy(e); > } > > -/* > - * Given expression `e1' and `e2', returns the leaf of the longest > - * sub-expression of `e1' not containing 'e2. > - */ > -struct expr *expr_simplify_unmet_dep(struct expr *e1, struct expr *e2) > -{ > - struct expr *ret; > - > - switch (e1->type) { > - case E_OR: > - return expr_alloc_and( > - expr_simplify_unmet_dep(e1->left.expr, e2), > - expr_simplify_unmet_dep(e1->right.expr, e2)); > - case E_AND: { > - struct expr *e; > - e = expr_alloc_and(expr_copy(e1), expr_copy(e2)); > - e = expr_eliminate_dups(e); > - ret = (!expr_eq(e, e1)) ? e1 : NULL; > - expr_free(e); > - break; > - } > - default: > - ret = e1; > - break; > - } > - > - return expr_get_leftmost_symbol(ret); It looks like expr_get_leftmost_symbol() has no more callers left and could be removed with this patch? Thanks, Eugeniu. -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html