From c4850e7fee85527976519f6d55685706d41cb91b Mon Sep 17 00:00:00 2001 From: Sami Tolvanen Date: Wed, 10 Apr 2019 14:17:20 -0700 Subject: [PATCH 24/24] x86, build: allow LTO_CLANG and THINLTO to be selected Allow CONFIG_LTO_CLANG and CONFIG_THINLTO to be enabled. Signed-off-by: Sami Tolvanen --- arch/x86/Kconfig | 2 ++ arch/x86/Makefile | 5 +++++ 2 files changed, 7 insertions(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 4a64395bc35d..16f046d5abea 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -92,6 +92,8 @@ config X86 select ARCH_SUPPORTS_ACPI select ARCH_SUPPORTS_ATOMIC_RMW select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 + select ARCH_SUPPORTS_LTO_CLANG if X86_64 + select ARCH_SUPPORTS_THINLTO if X86_64 select ARCH_USE_BUILTIN_BSWAP select ARCH_USE_QUEUED_RWLOCKS select ARCH_USE_QUEUED_SPINLOCKS diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 00e378de8bc0..a1abc1e081ad 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -188,6 +188,11 @@ ifdef CONFIG_X86_64 KBUILD_LDFLAGS += $(call ld-option, -z max-page-size=0x200000) endif +ifdef CONFIG_LTO_CLANG +KBUILD_LDFLAGS += -plugin-opt=-code-model=kernel \ + -plugin-opt=-stack-alignment=$(if $(CONFIG_X86_32),4,8) +endif + # Workaround for a gcc prelease that unfortunately was shipped in a suse release KBUILD_CFLAGS += -Wno-sign-compare # -- 2.28.0