On Fri, May 31, 2019 at 7:47 AM Segher Boessenkool <segher@xxxxxxxxxxxxxxxxxxx> wrote: > ... > > Man, it did not like that when using "&=r"(0ULL) (hundreds of them): > > > > error: lvalue required in asm statement > > > > (I assume you wanted an early clobber on the input %3). > > You are saying there that you want to output to something that is constant 0. > Yeah that doesn't work ;-) > > You should put the earlyclobber on the output, to tell GCC that that output > (register) is clobbered early, i.e. before all inputs are used (so that GCC > then knows to not put that output in the same place as one of the inputs). > Like so: Thanks Segher. That fixed it for me. Jeff
