From: Sam Lunt <samueljlunt@xxxxxxxxx> commit b9c9ce4e598e012ca7c1813fae2f4d02395807de upstream. Python 3.8 changed the output of 'python-config --ldflags' to no longer include the '-lpythonX.Y' flag (this apparently fixed an issue loading modules with a statically linked Python executable). The libpython feature check in linux/build/feature fails if the Python library is not included in FEATURE_CHECK_LDFLAGS-libpython variable. This adds a check in the Makefile to determine if PYTHON_CONFIG accepts the '--embed' flag and passes that flag alongside '--ldflags' if so. tools/perf is the only place the libpython feature check is used. Signed-off-by: Sam Lunt <samuel.j.lunt@xxxxxxxxx> Tested-by: He Zhe <zhe.he@xxxxxxxxxxxxx> Link: http://lore.kernel.org/lkml/c56be2e1-8111-9dfe-8298-f7d0f9ab7431@xxxxxxxxxxxxx Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: trivial@xxxxxxxxxx Cc: stable@xxxxxxxxxx Link: http://lore.kernel.org/lkml/20200131181123.tmamivhq4b7uqasr@xxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- tools/perf/Makefile.config | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) --- a/tools/perf/Makefile.config +++ b/tools/perf/Makefile.config @@ -228,8 +228,17 @@ strip-libs = $(filter-out -l%,$(1)) PYTHON_CONFIG_SQ := $(call shell-sq,$(PYTHON_CONFIG)) +# Python 3.8 changed the output of `python-config --ldflags` to not include the +# '-lpythonX.Y' flag unless '--embed' is also passed. The feature check for +# libpython fails if that flag is not included in LDFLAGS +ifeq ($(shell $(PYTHON_CONFIG_SQ) --ldflags --embed 2>&1 1>/dev/null; echo $$?), 0) + PYTHON_CONFIG_LDFLAGS := --ldflags --embed +else + PYTHON_CONFIG_LDFLAGS := --ldflags +endif + ifdef PYTHON_CONFIG - PYTHON_EMBED_LDOPTS := $(shell $(PYTHON_CONFIG_SQ) --ldflags 2>/dev/null) + PYTHON_EMBED_LDOPTS := $(shell $(PYTHON_CONFIG_SQ) $(PYTHON_CONFIG_LDFLAGS) 2>/dev/null) PYTHON_EMBED_LDFLAGS := $(call strip-libs,$(PYTHON_EMBED_LDOPTS)) PYTHON_EMBED_LIBADD := $(call grep-libs,$(PYTHON_EMBED_LDOPTS)) -lutil PYTHON_EMBED_CCOPTS := $(shell $(PYTHON_CONFIG_SQ) --includes 2>/dev/null)
