Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-16 00:52:01 +00:00
Code Issues Packages Projects Releases Wiki Activity

btrfs: fix build when using M=fs/btrfs

Browse Source 
There are people building the module with M= that's supposed to be used
for external modules. This got broken in e9aa7c285d ("btrfs: enable
W=1 checks for btrfs").

  $ make M=fs/btrfs
  scripts/Makefile.lib:10: *** Recursive variable 'KBUILD_CFLAGS' references itself (eventually).  Stop.
  make: *** [Makefile:1755: modules] Error 2

There's a difference compared to 'make fs/btrfs/btrfs.ko' which needs
to rebuild a few more things and also the dependency modules need to be
available. It could fail with eg.

  WARNING: Symbol version dump "Module.symvers" is missing.
	   Modules may not have dependencies or modversions.

In some environments it's more convenient to rebuild just the btrfs
module by M= so let's make it work.

The problem is with recursive variable evaluation in += so the
conditional C options are stored in a temporary variable to avoid the
recursion.

Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
David Sterba 2021-03-17 11:43:13 +01:00
parent 3cb894972f
commit ebd99a6b34
1 changed files with 6 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
fs/btrfs/Makefile
View File

@ -7,10 +7,12 @@ subdir-ccflags-y += -Wmissing-format-attribute
subdir-ccflags-y += -Wmissing-prototypes
subdir-ccflags-y += -Wold-style-definition
subdir-ccflags-y += -Wmissing-include-dirs
subdir-ccflags-y += $(call cc-option, -Wunused-but-set-variable)
subdir-ccflags-y += $(call cc-option, -Wunused-const-variable)
subdir-ccflags-y += $(call cc-option, -Wpacked-not-aligned)
subdir-ccflags-y += $(call cc-option, -Wstringop-truncation)
condflags := \
$(call cc-option, -Wunused-but-set-variable) \
$(call cc-option, -Wunused-const-variable) \
$(call cc-option, -Wpacked-not-aligned) \
$(call cc-option, -Wstringop-truncation)
subdir-ccflags-y += $(condflags)
# The following turn off the warnings enabled by -Wextra
subdir-ccflags-y += -Wno-missing-field-initializers
subdir-ccflags-y += -Wno-sign-compare