kconfig: recursive checks drop file/lineno
This prevents segfault when getting filename and lineno in recursive
checks.
If the following snippet is found in Kconfig:
[Test code 1]
config FOO
bool
depends on BAR
select BAR
... without BAR defined; then there is a segfault.
Kconfig:34:error: recursive dependency detected!
Kconfig:34: symbol FOO depends on BAR
make[4]: *** [scripts/kconfig/Makefile:85: allnoconfig] Segmentation fault
This is because of the following. BAR is a fake entry created by
sym_lookup() with prop being NULL. In the recursive check, there is a
NULL check for prop to fall back to stack->sym->prop if stack->prop is
NULL. However, in this case, stack->sym points to the fake BAR entry
created by sym_lookup(), so prop is still NULL. prop was then referenced
without additional NULL checks, causing segfault.
As the previous email thread suggests, the file and lineno for select is
also wrong:
[Test code 2]
config FOO
bool
config BAR
bool
config FOO
bool "FOO"
depends on BAR
select BAR
$ make defconfig
*** Default configuration is based on 'x86_64_defconfig'
Kconfig:1:error: recursive dependency detected!
Kconfig:1: symbol FOO depends on BAR
Kconfig:4: symbol BAR is selected by FOO
[...]
Kconfig:4 should be Kconfig:10.
This patch deletes the wrong and segfault-prone filename/lineno
inference completely. With this patch, Test code 1 yields:
error: recursive dependency detected!
symbol FOO depends on BAR
symbol BAR is selected by FOO
Signed-off-by: HONG Yifan <elsk@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2 files changed
