https://sourceware.org/bugzilla/show_bug.cgi?id=21285
--- Comment #3 from H.J. Lu <hjl.tools at gmail dot com> --- (In reply to Cary Coutant from comment #2) > OK, suppose we have the following sequence of instructions: > > cmp $0x8b, %al > movl bar@GOT, %eax > mov bar@GOT(%ecx), %esp > > which assemble to: > > 0: 3c 8b cmp $0x8b,%al > 2: a1 00 00 00 00 mov 0x0,%eax > 7: 8b a1 00 00 00 00 mov 0x0(%ecx),%esp > > How is the linker supposed to distinguish the two mov instructions? We > cannot make this optimization based on looking at the opcodes -- we need > separate relocations to tell us which is which, unless it's OK to invalidate > 0xa1 as a valid modrm byte in this usage. > > Doesn't ld have the same problem? movl bar@GOT, %eax is only supported with the updated i386 psABI, which requires "mov name@GOT, %eax must be encoded with opcode 0x8b, not 0xa0, to allow linker optimization." -- You are receiving this mail because: You are on the CC list for the bug. _______________________________________________ bug-binutils mailing list bug-binutils@gnu.org https://lists.gnu.org/mailman/listinfo/bug-binutils
