On Wed, 3 Nov 2021 at 08:26, tongtiangen <tongtiangen@xxxxxxxxxx> wrote: > [...] > > Adding a function declaration in bpf_jit_comp64.c file cannot fix this compiler error: > AFAIK, there are two issues: 1. https://lore.kernel.org/llvm/202110290334.2zdMyRq4-lkp@xxxxxxxxx/ 2. https://lore.kernel.org/llvm/202111020610.9oy9Rr0G-lkp@xxxxxxxxx/ 1 is a warning when W=1 is enabled (missing prototype from -Wmissing-prototypes) 2 is an error, since the function is not defined when building CONFIG_ARCH_RV32I You are trying to address both issues in this patch. > .... > when CONFIG_BPF_JIT and CONFIG_ARCH_64I is open, There is the following compiler error (W=1): > error: no previous prototype for 'rv_bpf_fixup_exception' > .... > > To fix this compiler error, you need to make a declaration in a header file, which is also > the reason for introducing extable.h. > No, you don't need the header file. The forward declaration is sufficient to get rid of the warning, and the adding CONFIG_ARCH_RV64I fixes the RV32I build. Björn
