Re: [PATCH v2] Fix objtool with clang

[Jiri Olsa]

On Mon, Nov 28, 2016 at 05:40:46PM -0200, Arnaldo Carvalho de Melo wrote:

SNIP

>   LD       /tmp/build/perf/pmu-events/pmu-events-in.o
>   CC       /tmp/build/perf/arch/x86/util/intel-bts.o
>   CC       /tmp/build/perf/builtin-buildid-cache.o
>   CC       /tmp/build/perf/builtin-list.o
>   LD       /tmp/build/perf/arch/x86/util/libperf-in.o
>   MKDIR    /tmp/build/perf/arch/x86/tests/
>   CC       /tmp/build/perf/arch/x86/tests/regs_load.o
> /tmp/build/perf/.plugin_jbd2.o.cmd:3: *** empty variable name.  Stop.
> Makefile:192: recipe for target '/tmp/build/perf/plugin_jbd2-in.o' failed
> make[2]: *** [/tmp/build/perf/plugin_jbd2-in.o] Error 2
> Makefile.perf:591: recipe for target '/tmp/build/perf/libtraceevent-dynamic-list' failed
> make[1]: *** [/tmp/build/perf/libtraceevent-dynamic-list] Error 2
> make[1]: *** Waiting for unfinished jobs....

ok, reproduced..

the commit changes the output of the depfile for some reason,
and our fixdep does not handle it correctly and produce wrong
cmd file that failed to parse.. checking for fix

depfile changes ('+' is after the change):

-plugin_jbd2.o: plugin_jbd2.c /usr/include/stdc-predef.h \
+plugin_jbd2.o plugin_jbd2.o: plugin_jbd2.c /usr/include/stdc-predef.h \

jirka