On Fri, May 31, 2024 at 06:45:33PM -0700, John Hubbard wrote:

When building with clang via:

make LLVM=1 -C tools/testing/selftests

two distinct failures occur:

1. gcc requires -static-libasan in order to ensure that Address

Sanitizer's library is the first one loaded. However, this leads to build failures on clang, when building via:

   make LLVM=1 -C tools/testing/selftests

However, clang already does the right thing by default: it statically links the Address Sanitizer if -fsanitize is specified. Therefore, fix this by simply omitting -static-libasan for clang builds. And leave behind a comment, because the whole reason for static linking might not be obvious.

2. clang won't accept invocations of this form, but gcc will:

   $(CC) file1.c header2.h

Fix this by using selftests/lib.mk facilities for tracking local header file dependencies: add them to LOCAL_HDRS, leaving only the .c files to be passed to the compiler.

Reviewed-by: Ryan Roberts ryan.roberts@arm.com Signed-off-by: John Hubbard jhubbard@nvidia.com

Assuming that $(LLVM) is the correct conditional to test for:

Reviewed-by: Nathan Chancellor nathan@kernel.org

---

tools/testing/selftests/openat2/Makefile | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/openat2/Makefile b/tools/testing/selftests/openat2/Makefile index 254d676a2689..185dc76ebb5f 100644 --- a/tools/testing/selftests/openat2/Makefile +++ b/tools/testing/selftests/openat2/Makefile @@ -1,8 +1,18 @@ # SPDX-License-Identifier: GPL-2.0-or-later -CFLAGS += -Wall -O2 -g -fsanitize=address -fsanitize=undefined -static-libasan +CFLAGS += -Wall -O2 -g -fsanitize=address -fsanitize=undefined TEST_GEN_PROGS := openat2_test resolve_test rename_attack_test +# gcc requires -static-libasan in order to ensure that Address Sanitizer's +# library is the first one loaded. However, clang already statically links the +# Address Sanitizer if -fsanitize is specified. Therefore, simply omit +# -static-libasan for clang builds. +ifeq ($(LLVM),)

• CFLAGS += -static-libasan

+endif

+LOCAL_HDRS += helpers.h

include ../lib.mk -$(TEST_GEN_PROGS): helpers.c helpers.h

+$(TEST_GEN_PROGS): helpers.c

2.45.1

On Fri, May 31, 2024 at 06:45:34PM -0700, John Hubbard wrote:

gcc requires -static-libasan in order to ensure that Address Sanitizer's library is the first one loaded. However, this leads to build failures on clang, when building via:

make LLVM=1 -C tools/testing/selftests

However, clang already does the right thing by default: it statically links the Address Sanitizer if -fsanitize is specified. Therefore, simply omit -static-libasan for clang builds. And leave behind a comment, because the whole reason for static linking might not be obvious.

Cc: Ryan Roberts ryan.roberts@arm.com Signed-off-by: John Hubbard jhubbard@nvidia.com

Assuming that $(LLVM) is the correct conditional to test for:

Reviewed-by: Nathan Chancellor nathan@kernel.org

---

tools/testing/selftests/fchmodat2/Makefile | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/fchmodat2/Makefile b/tools/testing/selftests/fchmodat2/Makefile index 71ec34bf1501..4373cea79b79 100644 --- a/tools/testing/selftests/fchmodat2/Makefile +++ b/tools/testing/selftests/fchmodat2/Makefile @@ -1,6 +1,15 @@ # SPDX-License-Identifier: GPL-2.0-or-later -CFLAGS += -Wall -O2 -g -fsanitize=address -fsanitize=undefined -static-libasan $(KHDR_INCLUDES) +CFLAGS += -Wall -O2 -g -fsanitize=address -fsanitize=undefined $(KHDR_INCLUDES)

+# gcc requires -static-libasan in order to ensure that Address Sanitizer's +# library is the first one loaded. However, clang already statically links the +# Address Sanitizer if -fsanitize is specified. Therefore, simply omit +# -static-libasan for clang builds. +ifeq ($(LLVM),)

• CFLAGS += -static-libasan

+endif

TEST_GEN_PROGS := fchmodat2_test include ../lib.mk -- 2.45.1