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| author | Masahiro Yamada <masahiroy@kernel.org> | 2020-01-18 02:14:35 +0900 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-02-24 08:34:50 +0100 |
| commit | 4feefb5cd5859dfcd9e4ce1e6dd7265052c2da04 (patch) | |
| tree | bf41005dd5bb0e93cbd4093b7d1b7372da128e7b /scripts | |
| parent | afdf4de910986e50567c92b9e4ff901606013978 (diff) | |
kbuild: use -S instead of -E for precise cc-option test in Kconfig
[ 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>
Diffstat (limited to 'scripts')
| -rw-r--r-- | scripts/Kconfig.include | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/scripts/Kconfig.include b/scripts/Kconfig.include index 3b2861f47709..79455ad6b386 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 |