FROMLIST: kbuild: improve libelf detection

When `pkg-config --libs' wasn't used or didn't return anything useful,
the test for libelf would fail even if the headers and libraries were
available to kbuild via KBUILD_CFLAGS and KBUILD_LDFLAGS.

This makes the check in the core Makefile match the check that is done
in tools/objtool/Makefile. Specifically, the C compiler is passed the
full KBUILD_CFLAGS and KBUILD_LDFLAGS, which may have set up additional
sysroot/include/library search paths to find libelf.

Signed-off-by: Alistair Delva <adelva@google.com>
Link: https://lore.kernel.org/lkml/20210112190010.1582888-1-adelva@google.com/
Bug: 175705438
Change-Id: I06b0997c2df8545877d8b2d29b7a3045551c92e2
This commit is contained in:
Alistair Delva
2021-01-11 12:04:38 -08:00
parent da8c4ad2d7
commit e70e24e78e

View File

@@ -1075,8 +1075,9 @@ export mod_sign_cmd
HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
has_libelf = $(call try-run,\
echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
has_libelf := $(call try-run,\
echo "int main() {}" | \
$(HOSTCC) $(KBUILD_HOSTCFLAGS) -xc -o /dev/null $(KBUILD_HOSTLDFLAGS) $(HOST_LIBELF_LIBS) -,1,0)
ifdef CONFIG_STACK_VALIDATION
ifeq ($(has_libelf),1)