linux-stable/fs/btrfs/Makefile
David Sterba ebd99a6b34 btrfs: fix build when using M=fs/btrfs
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>
2021-03-17 19:42:18 +01:00

43 lines
1.9 KiB
Makefile

# SPDX-License-Identifier: GPL-2.0
# Subset of W=1 warnings
subdir-ccflags-y += -Wextra -Wunused -Wno-unused-parameter
subdir-ccflags-y += -Wmissing-declarations
subdir-ccflags-y += -Wmissing-format-attribute
subdir-ccflags-y += -Wmissing-prototypes
subdir-ccflags-y += -Wold-style-definition
subdir-ccflags-y += -Wmissing-include-dirs
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 += $(condflags)
# The following turn off the warnings enabled by -Wextra
subdir-ccflags-y += -Wno-missing-field-initializers
subdir-ccflags-y += -Wno-sign-compare
subdir-ccflags-y += -Wno-type-limits
obj-$(CONFIG_BTRFS_FS) := btrfs.o
btrfs-y += super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \
file-item.o inode-item.o disk-io.o \
transaction.o inode.o file.o tree-defrag.o \
extent_map.o sysfs.o struct-funcs.o xattr.o ordered-data.o \
extent_io.o volumes.o async-thread.o ioctl.o locking.o orphan.o \
export.o tree-log.o free-space-cache.o zlib.o lzo.o zstd.o \
compression.o delayed-ref.o relocation.o delayed-inode.o scrub.o \
reada.o backref.o ulist.o qgroup.o send.o dev-replace.o raid56.o \
uuid-tree.o props.o free-space-tree.o tree-checker.o space-info.o \
block-rsv.o delalloc-space.o block-group.o discard.o reflink.o \
subpage.o
btrfs-$(CONFIG_BTRFS_FS_POSIX_ACL) += acl.o
btrfs-$(CONFIG_BTRFS_FS_CHECK_INTEGRITY) += check-integrity.o
btrfs-$(CONFIG_BTRFS_FS_REF_VERIFY) += ref-verify.o
btrfs-$(CONFIG_BLK_DEV_ZONED) += zoned.o
btrfs-$(CONFIG_BTRFS_FS_RUN_SANITY_TESTS) += tests/free-space-tests.o \
tests/extent-buffer-tests.o tests/btrfs-tests.o \
tests/extent-io-tests.o tests/inode-tests.o tests/qgroup-tests.o \
tests/free-space-tree-tests.o tests/extent-map-tests.o