On Fri, Apr 23, 2021 at 5:19 AM Nathan Chancellor <nathan@xxxxxxxxxx> wrote: > > Normally, invocations of $(HOSTCC) include $(KBUILD_HOSTLDFLAGS), which > in turn includes $(HOSTLDFLAGS), which allows users to pass in their own > flags when linking. However, the 'has_libelf' test does not, meaning > that if a user requests a specific linker via HOSTLDFLAGS=-fuse-ld=..., > it is not respected and the build might error. > > For example, if a user building with clang wants to use all of the LLVM > tools without any GNU tools, they might remove all of the GNU tools from > their system or PATH then build with > > $ make HOSTLDFLAGS=-fuse-ld=lld LLVM=1 LLVM_IAS=1 > > which says use all of the LLVM tools, the integrated assembler, and > ld.lld for linking host executables. Without this change, the build will > error because $(HOSTCC) uses its default linker, rather than the one > requested via -fuse-ld=..., which is GNU ld in clang's case in a default > configuration. > > error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please > install libelf-dev, libelf-devel or elfutils-libelf-devel > make[1]: *** [Makefile:1260: prepare-objtool] Error 1 > > Add $(KBUILD_HOSTLDFLAGS) to the 'has_libelf' test so that the linker > choice is respected. > > Link: https://github.com/ClangBuiltLinux/linux/issues/479 > Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx> > --- I applied this since the MW is opening shortly. However, I believe the right thing to do is to kill the pointless check entirely. > Makefile | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/Makefile b/Makefile > index bc19584fee59..1535b32c8baa 100644 > --- a/Makefile > +++ b/Makefile > @@ -1092,7 +1092,7 @@ 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) > + echo "int main() {}" | $(HOSTCC) $(KBUILD_HOSTLDFLAGS) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0) > > ifdef CONFIG_STACK_VALIDATION > ifeq ($(has_libelf),1) > > base-commit: bf05bf16c76bb44ab5156223e1e58e26dfe30a88 > -- > 2.31.1.362.g311531c9de > -- Best Regards Masahiro Yamada
