Hello! For some reason simplify_subreg does not like stack pointer. We call simplify_subreg when printing address operands, so we have to prevent SImode subregs of stack pointers from going into the address. 2012-08-01 Uros Bizjak * config/i386/i386.c (ix86_address_subreg_operand): Reject stack pointer. (ix86_print_operand_address): Assert that parts.base and parts.index are non-NULL after call to simplify_subreg. Tested on x86_64-pc-linux-gnu {,-m32} and committed to mainline SVN. The patch will be backported to 4.7 branch. Uros.