The semantics of `--undefined` differ between ld.bfd and ld.lld:
$ echo | gcc -x c -c - -o a.o
$ echo "EXTERN(test)" > a.lds
$ ld.bfd a.o -t a.lds -o - 2>/dev/null && objdump -t | grep test
0000000000000000 *UND* 0000000000000000 test
$ ld.lld a.o -t a.lds -o - 2>/dev/null && objdump -t | grep test
$
When building with CONFIG_STM=m, there are no in-kernel users of memcat_p()
and ld.lld discards this symbol because it's linked in via --no-whole-archive.
It's marked as undefined by a linker script but ld.lld discards it anyway (as
seen in the above snippet).
Work around the ld.lld behavior by moving the object file to obj-y.
Signed-off-by: Ilie Halip <ilie.halip@xxxxxxxxx>
Link: https://github.com/ClangBuiltLinux/linux/issues/515
---
lib/Makefile | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/lib/Makefile b/lib/Makefile
index 93217d44237f..eac343b81f77 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -30,7 +30,7 @@ lib-y := ctype.o string.o vsprintf.o cmdline.o \
flex_proportions.o ratelimit.o show_mem.o \
is_single_threaded.o plist.o decompress.o kobject_uevent.o \
earlycpio.o seq_buf.o siphash.o dec_and_lock.o \
- nmi_backtrace.o nodemask.o win_minmax.o memcat_p.o
+ nmi_backtrace.o nodemask.o win_minmax.o
lib-$(CONFIG_PRINTK) += dump_stack.o
lib-$(CONFIG_MMU) += ioremap.o
@@ -45,7 +45,7 @@ obj-y += bcd.o sort.o parser.o debug_locks.o random32.o \
bsearch.o find_bit.o llist.o memweight.o kfifo.o \
percpu-refcount.o rhashtable.o \
once.o refcount.o usercopy.o errseq.o bucket_locks.o \
- generic-radix-tree.o
+ generic-radix-tree.o memcat_p.o
obj-$(CONFIG_STRING_SELFTEST) += test_string.o
obj-y += string_helpers.o
obj-$(CONFIG_TEST_STRING_HELPERS) += test-string_helpers.o
base-commit: ee02f9544ebd8d38900dfe955710897b99483686
--
2.17.1
