From: Xie XiuQi <xiexiuqi@xxxxxxxxxx> Commit 97d5f2e9ee12 ("tools api fs: More thread safety for global filesystem variables") introduces pthread_once, so the libpthread should be added at link time, or we'll meet the following compile error when 'make -C tools/mm': gcc -Wall -Wextra -I../lib/ -o page-types page-types.c ../lib/api/libapi.a ~/linux/tools/lib/api/fs/fs.c:146: undefined reference to `pthread_once' ~/linux/tools/lib/api/fs/fs.c:147: undefined reference to `pthread_once' ~/linux/tools/lib/api/fs/fs.c:148: undefined reference to `pthread_once' ~/linux/tools/lib/api/fs/fs.c:149: undefined reference to `pthread_once' ~/linux/tools/lib/api/fs/fs.c:150: undefined reference to `pthread_once' /usr/bin/ld: ../lib/api/libapi.a(libapi-in.o):~/linux/tools/lib/api/fs/fs.c:151: more undefined references to `pthread_once' follow collect2: error: ld returned 1 exit status make: *** [Makefile:22: page-types] Error 1 Fixes: 97d5f2e9ee12 ("tools api fs: More thread safety for global filesystem variables") Signed-off-by: Xie XiuQi <xiexiuqi@xxxxxxxxxx> Acked-by: Ian Rogers <irogers@xxxxxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> --- v3: add it to both CFLAGS and LDFLAGS v2: use '-pthread' instead of -lpthread' --- tools/mm/Makefile | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/mm/Makefile b/tools/mm/Makefile index 6c1da51f4177..1c5606cc3334 100644 --- a/tools/mm/Makefile +++ b/tools/mm/Makefile @@ -8,8 +8,8 @@ TARGETS=page-types slabinfo page_owner_sort LIB_DIR = ../lib/api LIBS = $(LIB_DIR)/libapi.a -CFLAGS += -Wall -Wextra -I../lib/ -LDFLAGS += $(LIBS) +CFLAGS += -Wall -Wextra -I../lib/ -pthread +LDFLAGS += $(LIBS) -pthread all: $(TARGETS) -- 2.25.1