| Message ID | 20220404210525.725611-1-herton@redhat.com (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
| Series | tools/power/x86/intel-speed-select: fix build failure when using -Wl,--as-needed | expand |
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@redhat.com> > --- > 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)
On Mon, 2022-04-04 at 18:05 -0300, Herton R. Krzesinski wrote: > Build of intel-speed-select will fail if you run: > > $ LDFLAGS="-Wl,--as-needed" /usr/bin/make V=1 We realized this for some OS recently have an internal patch. So agree with the change. > ... > 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' > ... > > 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@redhat.com> Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> > --- > 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)
Hi All, On 4/4/22 23:05, 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' > ... > > 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@redhat.com> Thank you for your patch, I've applied this patch to my review-hans branch: https://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86.git/log/?h=review-hans I've also added this to my fixes branch and it will be included when I send the next fixes for 5.18 pull-req to Linus. Once I've run some tests on this branch the patches there will be added to the platform-drivers-x86/for-next branch and eventually will be included in the pdx86 pull-request to Linus for the next merge-window. Regards, Hans > --- > 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)
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)
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' ... 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@redhat.com> --- tools/power/x86/intel-speed-select/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)