Skip to contentSkip to conversation

FAILED: patch "[PATCH] kbuild: Disable -Wpointer-to-enum-cast" failed to apply to 4.14-stable tree

PATCH [email protected] 1 participant 1 message Mar 23, 2020

Subsystems (2)
lore
Share & tools
lore

[email protected]

author maintainer
#0 lore raw

The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 82f2bc2fcc0160d6f82dd1ac64518ae0a4dd183f Mon Sep 17 00:00:00 2001
From: Nathan Chancellor <[email protected]>
Date: Wed, 11 Mar 2020 12:41:21 -0700
Subject: [PATCH] kbuild: Disable -Wpointer-to-enum-cast

Clang's -Wpointer-to-int-cast deviates from GCC in that it warns when casting to enums. The kernel does this in certain places, such as device tree matches to set the version of the device being used, which allows the kernel to avoid using a gigantic union.

https://elixir.bootlin.com/linux/v5.5.8/source/drivers/ata/ahci_brcm.c#L428
https://elixir.bootlin.com/linux/v5.5.8/source/drivers/ata/ahci_brcm.c#L402
https://elixir.bootlin.com/linux/v5.5.8/source/include/linux/mod_devicetable.h#L264

To avoid a ton of false positive warnings, disable this particular part of the warning, which has been split off into a separate diagnostic so that the entire warning does not need to be turned off for clang. It will be visible under W=1 in case people want to go about fixing these easily and enabling the warning treewide.

scripts/Makefile.extrawarn +1 -0
index ecddf83ac142..ca08f2fe7c34 100644
@@ -48,6 +48,7 @@ KBUILD_CFLAGS += -Wno-initializer-overrides
 KBUILD_CFLAGS += -Wno-format
 KBUILD_CFLAGS += -Wno-sign-compare
 KBUILD_CFLAGS += -Wno-format-zero-length
+KBUILD_CFLAGS += $(call cc-disable-warning, pointer-to-enum-cast)
 endif
 
 endif