On Thu, May 02, 2024 at 06:58:20PM -0700, John Hubbard wrote:
First of all, in order to build with clang at all, one must first apply Valentin Obst's build fix for LLVM [1]. Once that is done, then when building with clang, via:
make LLVM=1 -C tools/testing/selftests...the following error occurs:
clang: error: cannot specify -o when generating multiple output files
This is because clang, unlike gcc, won't accept invocations of this form:
clang file1.c header2.hWhile trying to fix this, I noticed that:
a) selftests/lib.mk already avoids the problem, and
b) The binderfs Makefile indavertently bypasses the selftests/lib.mk build system, and quitely uses Make's implicit build rules for .c files instead.
The Makefile attempts to set up both a dependency and a source file, neither of which was needed, because lib.mk is able to automatically handle both. This line:
binderfs_test: binderfs_test.c...causes Make's implicit rules to run, which builds binderfs_test without ever looking at lib.mk.
Fix this by simply deleting the "binderfs_test:" Makefile target and letting lib.mk handle it instead.
[1] https://lore.kernel.org/all/20240329-selftests-libmk-llvm-rfc-v1-1-2f9ed7d1c...
Fixes: 6e29225af902 ("binderfs: port tests to test harness infrastructure") Cc: Christian Brauner brauner@kernel.org Signed-off-by: John Hubbard jhubbard@nvidia.com
Reviewed-by: Christian Brauner brauner@kernel.org