The kernel configuration phase is now tightly coupled with the compiler in use. It will be nice to show the compiler information in Kconfig. The compiler information will be displayed like this: $ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- config scripts/kconfig/conf --oldaskconfig Kconfig * * Linux/arm64 4.16.0-rc1 Kernel Configuration * * * Compiler: aarch64-linux-gnu-gcc (Linaro GCC 7.2-2017.11) 7.2.1 20171011 * * * General setup * Compile also drivers which will not load (COMPILE_TEST) [N/y/?] If you use GUI methods such as menuconfig, it will be displayed in the top menu. This is simply implemented by using the 'comment' statement. So, it will be saved into the .config file as well. This commit has a very important meaning. If the compiler is upgraded, Kconfig must be re-run since different compilers have different sets of supported options. All referenced environments are written to include/config/auto.conf.cmd so that any environment change triggers syncconfig, and prompt the user to input new values if needed. With this commit, something like follows will be added to include/config/auto.conf.cmd ifneq "$(CC_VERSION_TEXT)" "aarch64-linux-gnu-gcc (Linaro GCC 7.2-2017.11) 7.2.1 20171011" include/config/auto.conf: FORCE endif Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> --- Changes in v5: None Changes in v4: - Add comment to arch/x86/um/Kconfig as well Changes in v3: None Changes in v2: None Kconfig | 2 ++ Makefile | 2 ++ arch/x86/um/Kconfig | 2 ++ 3 files changed, 6 insertions(+) diff --git a/Kconfig b/Kconfig index 4af1b42..5b55d87 100644 --- a/Kconfig +++ b/Kconfig @@ -5,4 +5,6 @@ # mainmenu "Linux/$(ARCH) $(KERNELVERSION) Kernel Configuration" +comment "Compiler: $(CC_VERSION_TEXT)" + source "arch/$(SRCARCH)/Kconfig" diff --git a/Makefile b/Makefile index 58afa07..defb383 100644 --- a/Makefile +++ b/Makefile @@ -442,6 +442,8 @@ export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL export KBUILD_ARFLAGS +export CC_VERSION_TEXT := $(shell $(CC) --version | head -n 1) + # When compiling out-of-tree modules, put MODVERDIR in the module # tree rather than in the kernel tree. The kernel tree might # even be read-only. diff --git a/arch/x86/um/Kconfig b/arch/x86/um/Kconfig index 6a15c4d..a992f8e 100644 --- a/arch/x86/um/Kconfig +++ b/arch/x86/um/Kconfig @@ -1,6 +1,8 @@ # SPDX-License-Identifier: GPL-2.0 mainmenu "User Mode Linux/$(SUBARCH) $(KERNELVERSION) Kernel Configuration" +comment "Compiler: $(CC_VERSION_TEXT)" + source "arch/um/Kconfig.common" menu "UML-specific options" -- 2.7.4 -- 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