Linus Torvalds writes: (Summary) Both in the sense of "this kernel
config option depends on the compiler supporting flag XYZ" but also in
the sense of "the use flag ABC depends on not only compiler support,
but also on whether the kernel was configured for profiling" or
whatever.
whatever.
Then the actual Makefile parts would be things like Then the actual Makefile parts would be things like CFLAGS-$(CONFIG_CC_SPLIT_DWARF) += -gsplit_dwarf
CFLAGS-$(CONFIG_CC_SPLIT_DWARF) += -gsplit_dwarf
because the Kconfig phase would already have all the logic for whether (a) gcc actually supports -gsplit-dwarf at all and (b) whether the user actually asked for split debug info.
user actually asked for split debug info.
And we'd not have the performance issues that made that whole caching thing be an issue, because the actual gcc support testing would only happen at Kconfig time.
happen at Kconfig time.
..
whatever.
Then the actual Makefile parts would be things like Then the actual Makefile parts would be things like CFLAGS-$(CONFIG_CC_SPLIT_DWARF) += -gsplit_dwarf
CFLAGS-$(CONFIG_CC_SPLIT_DWARF) += -gsplit_dwarf
because the Kconfig phase would already have all the logic for whether (a) gcc actually supports -gsplit-dwarf at all and (b) whether the user actually asked for split debug info.
user actually asked for split debug info.
And we'd not have the performance issues that made that whole caching thing be an issue, because the actual gcc support testing would only happen at Kconfig time.
happen at Kconfig time.
..