On 4/4/22 17:05, Herton R. Krzesinski wrote:
Build of intel-speed-select will fail if you run:
$ LDFLAGS="-Wl,--as-needed" /usr/bin/make V=1
...
gcc -O2 -Wall -g -D_GNU_SOURCE -Iinclude -I/usr/include/libnl3 -Wl,--as-needed -lnl-genl-3 -lnl-3 intel-speed-select-in.o -o intel-speed-select
/usr/bin/ld: intel-speed-select-in.o: in function `handle_event':
(...)/linux/tools/power/x86/intel-speed-select/hfi-events.c:189: undefined reference to `nlmsg_hdr'
...
Srinivas, This is important as it blocks ARK (ie think of RHEL-next)
kernel builds and blocks us from bringing this code into current
versions of RHEL.
Just an FYI,
P.
In this case the problem is that order when linking matters when using
the flag -Wl,--as-needed, symbols not used at that point are discarded.
So since intel-speed-select-in.o comes after, at that point the
libraries/symbols are already discarded and then missing/undefined
references are reported.
To fix this, make sure we specify LDFLAGS after the object file.
Signed-off-by: Herton R. Krzesinski <herton@xxxxxxxxxx>
---
tools/power/x86/intel-speed-select/Makefile | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/power/x86/intel-speed-select/Makefile b/tools/power/x86/intel-speed-select/Makefile
index 846f785e278d..7221f2f55e8b 100644
--- a/tools/power/x86/intel-speed-select/Makefile
+++ b/tools/power/x86/intel-speed-select/Makefile
@@ -42,7 +42,7 @@ ISST_IN := $(OUTPUT)intel-speed-select-in.o
$(ISST_IN): prepare FORCE
$(Q)$(MAKE) $(build)=intel-speed-select
$(OUTPUT)intel-speed-select: $(ISST_IN)
- $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $< -o $@
+ $(QUIET_LINK)$(CC) $(CFLAGS) $< $(LDFLAGS) -o $@
clean:
rm -f $(ALL_PROGRAMS)
