On Thu, Oct 29, 2020 at 11:20 AM Fangrui Song maskray@google.com wrote:
Commit 39d114ddc682 ("arm64: add KASAN support") added .weak directives to arch/arm64/lib/mem*.S instead of changing the existing SYM_FUNC_START_PI macros. This can lead to the assembly snippet `.weak memcpy ... .globl memcpy` which will produce a STB_WEAK memcpy with GNU as but STB_GLOBAL memcpy with LLVM's integrated assembler before LLVM 12. LLVM 12 (since https://reviews.llvm.org/D90108) will error on such an overridden symbol binding.
Use the appropriate SYM_FUNC_START_WEAK_PI instead.
Fixes: 39d114ddc682 ("arm64: add KASAN support") Reported-by: Sami Tolvanen samitolvanen@google.com Signed-off-by: Fangrui Song maskray@google.com Cc: stable@vger.kernel.org
arch/arm64/lib/memcpy.S | 3 +-- arch/arm64/lib/memmove.S | 3 +-- arch/arm64/lib/memset.S | 3 +-- 3 files changed, 3 insertions(+), 6 deletions(-)
Thanks for the patch! This fixes the build with Clang 12 + LLVM_IAS=1, and also builds and boots with gcc 9.3 and Clang 12 without IAS.
Tested-by: Sami Tolvanen samitolvanen@google.com
Sami