Rather than disable all warnings with -w, disable specific warnings. Predicate enabling the warnings on a recent version of bison. Tested with GCC 9.3.0 and clang 9.0.1.
Signed-off-by: Ian Rogers <irog...@google.com> --- tools/perf/util/Build | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/tools/perf/util/Build b/tools/perf/util/Build index 935ba132614c..c1692076469c 100644 --- a/tools/perf/util/Build +++ b/tools/perf/util/Build @@ -234,9 +234,17 @@ endif CFLAGS_parse-events-flex.o += $(flex_flags) CFLAGS_pmu-flex.o += $(flex_flags) CFLAGS_expr-flex.o += $(flex_flags) -CFLAGS_parse-events-bison.o += -DYYENABLE_NLS=0 -w -CFLAGS_pmu-bison.o += -DYYENABLE_NLS=0 -DYYLTYPE_IS_TRIVIAL=0 -w -CFLAGS_expr-bison.o += -DYYENABLE_NLS=0 -DYYLTYPE_IS_TRIVIAL=0 -w + +bison_flags := -DYYENABLE_NLS=0 +BISON_GE_353 := $(shell expr $(shell $(BISON) --version | grep bison | sed -e 's/.\+ \([0-9]\+\).\([0-9]\+\).\([0-9]\+\)/\1\2\3/g') \>\= 353) +ifeq ($(BISON_GE_353),1) + bison_flags += -Wno-unused-parameter -Wno-nested-externs -Wno-error=implicit-function-declaration +else + bison_flags += -w +endif +CFLAGS_parse-events-bison.o += $(bison_flags) +CFLAGS_pmu-bison.o += -DYYLTYPE_IS_TRIVIAL=0 $(bison_flags) +CFLAGS_expr-bison.o += -DYYLTYPE_IS_TRIVIAL=0 $(bison_flags) $(OUTPUT)util/parse-events.o: $(OUTPUT)util/parse-events-flex.c $(OUTPUT)util/parse-events-bison.c $(OUTPUT)util/pmu.o: $(OUTPUT)util/pmu-flex.c $(OUTPUT)util/pmu-bison.c -- 2.27.0.111.gc72c7da667-goog
