2023-07-25 09:29:57

by Xie XiuQi

Subject: [PATCH] tools/mm: fix undefined reference to pthread_once

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 <[email protected]>
---
tools/mm/Makefile | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/mm/Makefile b/tools/mm/Makefile
index 6c1da51f4177..9997b2e401ae 100644
--- a/tools/mm/Makefile
+++ b/tools/mm/Makefile
@@ -9,7 +9,7 @@ LIB_DIR = ../lib/api
LIBS = $(LIB_DIR)/libapi.a

CFLAGS += -Wall -Wextra -I../lib/
-LDFLAGS += $(LIBS)
+LDFLAGS += $(LIBS) -lpthread

all: $(TARGETS)

--
2.25.1

2023-07-26 18:17:02

by Ian Rogers

Subject: Re: [PATCH] tools/mm: fix undefined reference to pthread_once

On Tue, Jul 25, 2023 at 2:24 AM Xie XiuQi <[email protected]> wrote:
>
> 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 <[email protected]>

Apologies.
Acked-by: Ian Rogers <[email protected]>

Alternatively we could #ifdef the behavior, but this way is cleaner imo.

Thanks,
Ian

> ---
> tools/mm/Makefile | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/mm/Makefile b/tools/mm/Makefile
> index 6c1da51f4177..9997b2e401ae 100644
> --- a/tools/mm/Makefile
> +++ b/tools/mm/Makefile
> @@ -9,7 +9,7 @@ LIB_DIR = ../lib/api
> LIBS = $(LIB_DIR)/libapi.a
>
> CFLAGS += -Wall -Wextra -I../lib/
> -LDFLAGS += $(LIBS)
> +LDFLAGS += $(LIBS) -lpthread
>
> all: $(TARGETS)
>
> --
> 2.25.1
>