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It cause more symbol cost > in the "*.o" files. For ABS symbols, if several "*.o" files are linked > together, there will be several extra symbols. Llvm works OK by creating > ABS symbol (I tried, but forgot the details), but GNU AS is not. Because > it applies its ABS value to addend (, Qinggang has investigated before.). Elf64_Sym is relatively smaller with just 24 bytes (unlike other control structures in ELF). To bypass a specific oddity in relocatable linking, consider using a SHN_ABS symbol. You can define a SHN_ABS STB_GLOBAL STV_HIDDEN symbol to avoid redundant copies within the link unit. Duplicate SHN_ABS symbols of the same st_value do not cause duplicate symbol definitions (except mold). Alternatively, use STB_WEAK to make the deduplication intention clearer. > > On Fri, Mar 22, 2024 at 1:29=E2=80=AFAM mengqinggang wrote: > > I just saw this was pushed as commit daeda14191c1710ce967259a47ef4e0a3f= b6eebf. > > > > The addition of the generic elf_backend_is_rela_normal flag seems like > > something a global maintainer should take a closer look at. > > In particular, I'm curious if Alan, the author of the "rela_normal" > > commit (b491616acb5462a3694160ffef6413c160fed10a), has any thoughts on > > this. > > > > The idea appears to be > > (https://github.com/loongson/la-abi-specs/blob/release/laelf.adoc#:~:te= xt=3DR_LARCH_ALIGN) > > > > .text > > break 1 > > .p2align 4, , 8 // R_LARCH_ALIGN .text+0x0804 > > break 8 > > > > In a relocatable link, the addend associated with the STT_SECTION > > symbol is kept unchanged. > > Relocatable link merge input file text sections into one text section. > If a relocation reference a section symbol, the addend would add the > section offset in the final one text section. This is exactly my concern. Using a STT_SECTION symbol requires a special c= ase. https://inbox.sourceware.org/binutils/20020506132720.GT3698@bubble.sa.bigpo= nd.net.au/ specifies > mips is the fly in the ointment here, and the reason for elf_backend_rela= _normal. !rela_normal is weird, and we should not introduce more weird stuff (R_LARCH_ALIGN referencing STT_SECTION).