Re: [PATCH v2] kvm: x86: mmu: Add cast to negated bitmasks in update_permission_bitmask()

From: Joe Perches
Date: Mon Jun 25 2018 - 13:51:05 EST


On Mon, 2018-06-25 at 10:35 -0700, Matthias Kaehlcke wrote:
> Some other instances of the warning that have been addressed are:
> commit 644d87dccdc69cf79834a72ed0c889580d6af32a
> commit e2a5dca753d1cdc3212519023ed8a13e13f5495b
> commit dae1a432ab1fe79ae53129ededeaece35a2dc14d
> commit d1600401faad4bc186bfdb291d8af644465e20bd
> commit a45463cbf3f9dcdae683033c256f50bded513d6a

I think all these implicit conversion warnings are senseless
and should really be silenced by setting them only to be
output at W=3 with all the other non-static and generally
unnecessary signed/unsigned conversions

---
scripts/Makefile.extrawarn | 1 +
1 file changed, 1 insertion(+)

diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn
index 8d5357053f86..9b1d0d59e8d0 100644
--- a/scripts/Makefile.extrawarn
+++ b/scripts/Makefile.extrawarn
@@ -46,6 +46,7 @@ warning-2 += $(call cc-option, -Wunused-macros)
warning-3 := -Wbad-function-cast
warning-3 += -Wcast-qual
warning-3 += -Wconversion
+warning-3 += $(call cc-option -Wconstant-conversion)
warning-3 += -Wpacked
warning-3 += -Wpadded
warning-3 += -Wpointer-arith