[ Sorry for dropping the ball on this. ] On Tue, Sep 17, 2019 at 11:59:02PM -0400, Jason Merrill wrote: > On 9/16/19 1:12 PM, Marek Polacek wrote: > > On Sun, Sep 15, 2019 at 10:18:29AM -0400, Jason Merrill wrote: > > > On 9/5/19 9:24 PM, Marek Polacek wrote: > > > > They use > > > > non_lvalue_loc, but that won't create a NON_LVALUE_EXPR wrapper around > > > > a location > > > > wrapper. > > > > > > That seems like the bug. maybe_lvalue_p should be true for > > > VIEW_CONVERT_EXPR. > > > > That makes sense but it breaks in tsubst_* which doesn't expect a > > NON_LVALUE_EXPR wrapped around a location wrapper. > > Hmm, why would we get that in a template when we don't get NON_LVALUE_EXPR > wrapped around other lvalue nodes?
I just retested the patch without the pt.c hunk and no longer see that problem, and the fold-const.c hunk still fixes the bogus error. Yay? So I think the following should be good to go: Bootstrapped/regtested on x86_64-linux, ok for trunk? 2019-12-06 Marek Polacek <pola...@redhat.com> PR c++/91678 - wrong error with decltype and location wrapper. * fold-const.c (maybe_lvalue_p): Handle VIEW_CONVERT_EXPR. * g++.dg/cpp0x/decltype73.C: New test. --- gcc/fold-const.c +++ gcc/fold-const.c @@ -2594,6 +2594,7 @@ maybe_lvalue_p (const_tree x) case TARGET_EXPR: case COND_EXPR: case BIND_EXPR: + case VIEW_CONVERT_EXPR: break; default: --- /dev/null +++ gcc/testsuite/g++.dg/cpp0x/decltype73.C @@ -0,0 +1,4 @@ +// PR c++/91678 - wrong error with decltype and location wrapper. +// { dg-do compile { target c++11 } } + +float* test(float* c) { return (decltype(c + 0))(float*)c; }