[PATCH] x86: Enable clang LTO for 32-bit as well

From: Nathan Chancellor
Date: Thu Apr 29 2021 - 19:26:55 EST


Commit b33fff07e3e3 ("x86, build: allow LTO to be selected") enabled
support for LTO for x86_64 but 32-bit works fine as well.

I tested the following config combinations:

* i386_defconfig + CONFIG_LTO_CLANG_FULL=y

* i386_defconfig + CONFIG_LTO_CLANG_THIN=y

* ARCH=i386 allmodconfig + CONFIG_LTO_CLANG_THIN=y

with LLVM 11.1.0, 12.0.0, and 13.0.0 from git without any build
failures. The defconfigs boot in QEMU with no new warnings.

Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx>
---
arch/x86/Kconfig | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 0fc82237414d..d8a919d9535e 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -97,8 +97,8 @@ config X86
select ARCH_SUPPORTS_DEBUG_PAGEALLOC
select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
select ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP if NR_CPUS <= 4096
- select ARCH_SUPPORTS_LTO_CLANG if X86_64
- select ARCH_SUPPORTS_LTO_CLANG_THIN if X86_64
+ select ARCH_SUPPORTS_LTO_CLANG
+ select ARCH_SUPPORTS_LTO_CLANG_THIN
select ARCH_USE_BUILTIN_BSWAP
select ARCH_USE_QUEUED_RWLOCKS
select ARCH_USE_QUEUED_SPINLOCKS

base-commit: d8201efe75e13146ebde433745c7920e15593baf
--
2.31.1.362.g311531c9de