[PATCH v4 26/31] gcov: remove CONFIG_GCOV_FORMAT_AUTODETECT

Masahiro Yamada
2018-05-17T06:19:16Z

CONFIG_GCOV_FORMAT_AUTODETECT compiles either gcc_3_4.c or gcc_4_7.c
according to your GCC version.

We can achieve the equivalent behavior by setting reasonable dependency
with the knowledge of the compiler version.

If GCC older than 4.7 is used, GCOV_FORMAT_3_4 is the default, but users
are still allowed to select GCOV_FORMAT_4_7 in case the newer format is
back-ported.

On the other hand, If GCC 4.7 or newer is used, there is no reason to
use GCOV_FORMAT_3_4, so it should be hidden.

If you downgrade the compiler to GCC 4.7 or older, oldconfig/syncconfig
will display a prompt for the choice because GCOV_FORMAT_3_4 becomes
visible as a new symbol.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
---

Changes in v4: None
Changes in v3: None
Changes in v2: None

kernel/gcov/Kconfig | 17 +++++------------
kernel/gcov/Makefile | 2 --
2 files changed, 5 insertions(+), 14 deletions(-)

diff --git a/kernel/gcov/Kconfig b/kernel/gcov/Kconfig
index 1276aab..1e3823f 100644
--- a/kernel/gcov/Kconfig
+++ b/kernel/gcov/Kconfig
@@ -53,23 +53,16 @@ config GCOV_PROFILE_ALL
choice
prompt "Specify GCOV format"
depends on GCOV_KERNEL
- default GCOV_FORMAT_AUTODETECT
---help---
- The gcov format is usually determined by the GCC version, but there are
+ The gcov format is usually determined by the GCC version, and the
+ default is chosen according to your GCC version. However, there are
exceptions where format changes are integrated in lower-version GCCs.
- In such a case use this option to adjust the format used in the kernel
- accordingly.
-
- If unsure, choose "Autodetect".
-
-config GCOV_FORMAT_AUTODETECT
- bool "Autodetect"
- ---help---
- Select this option to use the format that corresponds to your GCC
- version.
+ In such a case, change this option to adjust the format used in the
+ kernel accordingly.

config GCOV_FORMAT_3_4
bool "GCC 3.4 format"
+ depends on CC_IS_GCC && GCC_VERSION < 40700
---help---
Select this option to use the format defined by GCC 3.4.

diff --git a/kernel/gcov/Makefile b/kernel/gcov/Makefile
index c6c50e5..ff06d64 100644
--- a/kernel/gcov/Makefile
+++ b/kernel/gcov/Makefile
@@ -4,5 +4,3 @@ ccflags-y := -DSRCTREE='"$(srctree)"' -DOBJTREE='"$(objtree)"'
obj-y := base.o fs.o
obj-$(CONFIG_GCOV_FORMAT_3_4) += gcc_3_4.o
obj-$(CONFIG_GCOV_FORMAT_4_7) += gcc_4_7.o
-obj-$(CONFIG_GCOV_FORMAT_AUTODETECT) += $(call cc-ifversion, -lt, 0407, \
- gcc_3_4.o, gcc_4_7.o)
--
2.7.4