Linux Makefile : Why include/config/%. conf 总是被构建？

Question

我使用的是 Linux Makefile(4.2.0)。

如果我使用不存在的目标调用 make，例如“make ABCDEF”，则 make 始终重新制作目标:include/config/%.conf(第 570 行附近)，其配方为“ma​​kesilentoldconfig”。

下面是目标(第 556 行附近):

# Read in config
-include include/config/auto.conf

ifeq ($(KBUILD_EXTMOD),)
# Read in dependencies to all Kconfig* files, make sure to run
# oldconfig if changes are detected.
-include include/config/auto.conf.cmd

# To avoid any implicit rule to kick in, define an empty command
$(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;

# If .config is newer than include/config/auto.conf, someone tinkered
# with it and forgot to run make oldconfig.
# if auto.conf.cmd is missing then we are probably in a cleaned tree so
# we execute the config step to be sure to catch updated Kconfig files
include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
    $(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig

我只是想知道为什么这个目标“include/config/%.conf”总是被构建？甚至连目标也没有被调用。

有人可以帮助我吗？

Answer 1

使用 make -d 查看规则执行的原因