From: Masahiro Yamada <masahiroy@xxxxxxxxxx>
commit 3a7c733165a4799fa1beb262fe244bfbcdd1c163 upstream.
The support for __uint128_t is dependent on the target bit size.
GCC that defaults to the 32-bit can still build the 64-bit kernel
with -m64 flag passed.
However, $(cc-option,-D__SIZEOF_INT128__=0) is evaluated against the
default machine bit, which may not match to the kernel it is building.
Theoretically, this could be evaluated separately for 64BIT/32BIT.
config CC_HAS_INT128
bool
default !$(cc-option,$(m64-flag) -D__SIZEOF_INT128__=0) if 64BIT
default !$(cc-option,$(m32-flag) -D__SIZEOF_INT128__=0)
I simplified it more because the 32-bit compiler is unlikely to support
__uint128_t.
Fixes: c12d3362a74b ("int128: move __uint128_t compiler test to Kconfig")
Reported-by: George Spelvin <lkml@xxxxxxx>
Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Tested-by: George Spelvin <lkml@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
init/Kconfig | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -767,8 +767,7 @@ config ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
bool
config CC_HAS_INT128
- def_bool y
- depends on !$(cc-option,-D__SIZEOF_INT128__=0)
+ def_bool !$(cc-option,$(m64-flag) -D__SIZEOF_INT128__=0) && 64BIT
#
# For architectures that know their GCC __int128 support is sound
