From: Masahiro Yamada <masahiroy@xxxxxxxxxx> Subject: sparc,x86: vdso: remove meaningless undefining CONFIG_OPTIMIZE_INLINING The code, #undef CONFIG_OPTIMIZE_INLINING, is not working as expected because <linux/compiler_types.h> is parsed before vclock_gettime.c since 28128c61e08e ("kconfig.h: Include compiler types to avoid missed struct attributes"). Since then, <linux/compiler_types.h> is included really early by using the '-include' option. So, you cannot negate the decision of <linux/compiler_types.h> in this way. You can confirm it by checking the pre-processed code, like this: $ make arch/x86/entry/vdso/vdso32/vclock_gettime.i There is no difference with/without CONFIG_CC_OPTIMIZE_FOR_SIZE. It is about two years since 28128c61e08e. Nobody has reported a problem (or, nobody has even noticed the fact that this code is not working). It is ugly and unreliable to attempt to undefine a CONFIG option from C files, and anyway the inlining heuristic is up to the compiler. Just remove the broken code. Link: http://lkml.kernel.org/r/20200220110807.32534-1-masahiroy@xxxxxxxxxx Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx> Acked-by: Miguel Ojeda <miguel.ojeda.sandonis@xxxxxxxxx> Reviewed-by: Nathan Chancellor <natechancellor@xxxxxxxxx> Cc: Arnd Bergmann <arnd@xxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Masahiro Yamada <masahiroy@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Cc: David Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/sparc/vdso/vdso32/vclock_gettime.c | 4 ---- arch/x86/entry/vdso/vdso32/vclock_gettime.c | 4 ---- 2 files changed, 8 deletions(-) --- a/arch/sparc/vdso/vdso32/vclock_gettime.c~sparcx86-vdso-remove-meaningless-undefining-config_optimize_inlining +++ a/arch/sparc/vdso/vdso32/vclock_gettime.c @@ -4,10 +4,6 @@ #define BUILD_VDSO32 -#ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE -#undef CONFIG_OPTIMIZE_INLINING -#endif - #ifdef CONFIG_SPARC64 /* --- a/arch/x86/entry/vdso/vdso32/vclock_gettime.c~sparcx86-vdso-remove-meaningless-undefining-config_optimize_inlining +++ a/arch/x86/entry/vdso/vdso32/vclock_gettime.c @@ -1,10 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 #define BUILD_VDSO32 -#ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE -#undef CONFIG_OPTIMIZE_INLINING -#endif - #ifdef CONFIG_X86_64 /* _