From: =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= <rkrcmar@redhat.com>
Date: Wed, 13 Sep 2017 15:13:46 +0200
Subject: KVM: x86: fix clang build
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Patch-mainline: v4.14-rc1
Git-commit: 5153723388c8691b886eb9ad28dde92c01f9b191
References: bsc#1077761

Clang resolves __builtin_constant_p() to false even if the expression is
constant in the end.  The only purpose of that expression was to
differentiate a case where the following expression couldn't be checked
at compile-time, so we can just remove the check.

Clang handles the following two correctly.  Turn it into BUG_ON if there
are any more problems with this.

Fixes: d6321d493319 ("KVM: x86: generalize guest_cpuid_has_ helpers")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Acked-by: Alexander Graf <agraf@suse.de>
---
 arch/x86/kvm/cpuid.h |    1 -
 1 file changed, 1 deletion(-)

--- a/arch/x86/kvm/cpuid.h
+++ b/arch/x86/kvm/cpuid.h
@@ -59,7 +59,6 @@
 {
 	unsigned x86_leaf = x86_feature / 32;
 
-	BUILD_BUG_ON(!__builtin_constant_p(x86_leaf));
 	BUILD_BUG_ON(x86_leaf >= ARRAY_SIZE(reverse_cpuid));
 	BUILD_BUG_ON(reverse_cpuid[x86_leaf].function == 0);