On Fri, Jul 21, 2017 at 8:24 PM, Andrew Pinski <pins...@gmail.com> wrote: > Hi, > Due to the way bit-field access lower is done, we can get an > unitialized memory load and this causes the unitialized warning to > kick in. > The case we have is: > temp_1 = BIT_FIELD_REF<a, 0, 64> > temp_2 = BIT_INSERT<temp_1, V, P (N bits)> > BIT_FIELD_REF<a, 0, 64> = temp_2 > > What this patch does is similar to what was done for the case of > BIT_INSERT for unitialized ssa names (default) but for memory > accesses. > Note also tested with the bit-field lower pass added; this and the > fold-const.c/tree-ssa-sccvn.c patch (which was just committed) are > requirements to the lower pass. > > OK? Bootstrapped and tested on aarch64-linux-gnu with no regressions.
Ok. Thanks, Richard. > Thanks, > Andrew Pinski > * tree-ssa-uninit.c (warn_uninitialized_vars): Don't warn about memory > accesses where the use is for the first operand of a BIT_INSERT.
