[PATCH AUTOSEL 4.19 052/252] kconfig: fix broken dependency in randconfig-generated .config

[PATCH AUTOSEL 4.19 052/252] kconfig: fix broken dependency in randconfig-generated .config

[Sasha Levin]

From: Masahiro Yamada <masahiroy@kernel.org>

[ Upstream commit c8fb7d7e48d11520ad24808cfce7afb7b9c9f798 ]

Running randconfig on arm64 using KCONFIG_SEED=0x40C5E904 (e.g. on v5.5)
produces the .config with CONFIG_EFI=y and CONFIG_CPU_BIG_ENDIAN=y,
which does not meet the !CONFIG_CPU_BIG_ENDIAN dependency.

This is because the user choice for CONFIG_CPU_LITTLE_ENDIAN vs
CONFIG_CPU_BIG_ENDIAN is set by randomize_choice_values() after the
value of CONFIG_EFI is calculated.

When this happens, the has_changed flag should be set.

Currently, it takes the result from the last iteration. It should
accumulate all the results of the loop.

Fixes: 3b9a19e08960 ("kconfig: loop as long as we changed some symbols in randconfig")
Reported-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 scripts/kconfig/confdata.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c
index 0dde19cf74865..2caf5fac102a2 100644
--- a/scripts/kconfig/confdata.c
+++ b/scripts/kconfig/confdata.c
@@ -1314,7 +1314,7 @@ bool conf_set_all_new_symbols(enum conf_def_mode mode)
 
 		sym_calc_value(csym);
 		if (mode == def_random)
-			has_changed = randomize_choice_values(csym);
+			has_changed |= randomize_choice_values(csym);
 		else {
 			set_all_choice_values(csym);
 			has_changed = true;
-- 
2.20.1

[PATCH AUTOSEL 4.19 201/252] kbuild: use -S instead of -E for precise cc-option test in Kconfig

[Sasha Levin]

From: Masahiro Yamada <masahiroy@kernel.org>

[ Upstream commit 3bed1b7b9d79ca40e41e3af130931a3225e951a3 ]

Currently, -E (stop after the preprocessing stage) is used to check
whether the given compiler flag is supported.

While it is faster than -S (or -c), it can be false-positive. You need
to run the compilation proper to check the flag more precisely.

For example, -E and -S disagree about the support of
"--param asan-instrument-allocas=1".

$ gcc -Werror --param asan-instrument-allocas=1 -E -x c /dev/null -o /dev/null
$ echo $?
0

$ gcc -Werror --param asan-instrument-allocas=1 -S -x c /dev/null -o /dev/null
cc1: error: invalid --param name ‘asan-instrument-allocas’; did you mean ‘asan-instrument-writes’?
$ echo $?
1

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 scripts/Kconfig.include | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/Kconfig.include b/scripts/Kconfig.include
index 3b2861f47709b..79455ad6b3863 100644
--- a/scripts/Kconfig.include
+++ b/scripts/Kconfig.include
@@ -20,7 +20,7 @@ success = $(if-success,$(1),y,n)
 
 # $(cc-option,<flag>)
 # Return y if the compiler supports <flag>, n otherwise
-cc-option = $(success,$(CC) -Werror $(CLANG_FLAGS) $(1) -E -x c /dev/null -o /dev/null)
+cc-option = $(success,$(CC) -Werror $(CLANG_FLAGS) $(1) -S -x c /dev/null -o /dev/null)
 
 # $(ld-option,<flag>)
 # Return y if the linker supports <flag>, n otherwise
-- 
2.20.1