| Message ID | 20200306184137.3926946-2-ppalka@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | c++: Fix missing SFINAE when binding a bit-field to a reference (PR 93729) | expand |
On 3/6/20 1:41 PM, Patrick Palka wrote: > We are unconditionally emitting an error here, without first checking complain. > > This is not a regression, though I guess it could loosely be considered to be a > concepts bug, and the fix seems to be relatively harmless. Does this maybe look > OK for trunk, or should it wait for stage 1? This looks obvious enough to be OK for trunk. > gcc/cp/ChangeLog: > > PR c++/93729 > * call.c (convert_like_real): Check complain before emitting an error > about binding a bit-field to a reference. > > gcc/testsuite/ChangeLog: > > PR c++/93729 > * g++.dg/concepts/pr93729.C: New test. > --- > gcc/cp/call.c | 21 ++++++++++++--------- > gcc/testsuite/g++.dg/concepts/pr93729.C | 15 +++++++++++++++ > 2 files changed, 27 insertions(+), 9 deletions(-) > create mode 100644 gcc/testsuite/g++.dg/concepts/pr93729.C > > diff --git a/gcc/cp/call.c b/gcc/cp/call.c > index 85bbd043a1d..c0340d96f3c 100644 > --- a/gcc/cp/call.c > +++ b/gcc/cp/call.c > @@ -7730,15 +7730,18 @@ convert_like_real (conversion *convs, tree expr, tree fn, int argnum, > { > /* If the reference is volatile or non-const, we > cannot create a temporary. */ > - if (lvalue & clk_bitfield) > - error_at (loc, "cannot bind bit-field %qE to %qT", > - expr, ref_type); > - else if (lvalue & clk_packed) > - error_at (loc, "cannot bind packed field %qE to %qT", > - expr, ref_type); > - else > - error_at (loc, "cannot bind rvalue %qE to %qT", > - expr, ref_type); > + if (complain & tf_error) > + { > + if (lvalue & clk_bitfield) > + error_at (loc, "cannot bind bit-field %qE to %qT", > + expr, ref_type); > + else if (lvalue & clk_packed) > + error_at (loc, "cannot bind packed field %qE to %qT", > + expr, ref_type); > + else > + error_at (loc, "cannot bind rvalue %qE to %qT", > + expr, ref_type); > + } > return error_mark_node; > } > /* If the source is a packed field, and we must use a copy > diff --git a/gcc/testsuite/g++.dg/concepts/pr93729.C b/gcc/testsuite/g++.dg/concepts/pr93729.C > new file mode 100644 > index 00000000000..7397edb311d > --- /dev/null > +++ b/gcc/testsuite/g++.dg/concepts/pr93729.C > @@ -0,0 +1,15 @@ > +// { dg-do compile { target c++2a } } > + > +// PR c++/93729 > + > +struct B > +{ > + int a:4; > + int b:4; > +}; > + > +template<typename T> > +concept c1 > + = requires(T x, void(f)(int &)) { f(x.a); }; // { dg-bogus "cannot bind" } > + > +static_assert(!c1<B>); >
diff --git a/gcc/cp/call.c b/gcc/cp/call.c index 85bbd043a1d..c0340d96f3c 100644 --- a/gcc/cp/call.c +++ b/gcc/cp/call.c @@ -7730,15 +7730,18 @@ convert_like_real (conversion *convs, tree expr, tree fn, int argnum, { /* If the reference is volatile or non-const, we cannot create a temporary. */ - if (lvalue & clk_bitfield) - error_at (loc, "cannot bind bit-field %qE to %qT", - expr, ref_type); - else if (lvalue & clk_packed) - error_at (loc, "cannot bind packed field %qE to %qT", - expr, ref_type); - else - error_at (loc, "cannot bind rvalue %qE to %qT", - expr, ref_type); + if (complain & tf_error) + { + if (lvalue & clk_bitfield) + error_at (loc, "cannot bind bit-field %qE to %qT", + expr, ref_type); + else if (lvalue & clk_packed) + error_at (loc, "cannot bind packed field %qE to %qT", + expr, ref_type); + else + error_at (loc, "cannot bind rvalue %qE to %qT", + expr, ref_type); + } return error_mark_node; } /* If the source is a packed field, and we must use a copy diff --git a/gcc/testsuite/g++.dg/concepts/pr93729.C b/gcc/testsuite/g++.dg/concepts/pr93729.C new file mode 100644 index 00000000000..7397edb311d --- /dev/null +++ b/gcc/testsuite/g++.dg/concepts/pr93729.C @@ -0,0 +1,15 @@ +// { dg-do compile { target c++2a } } + +// PR c++/93729 + +struct B +{ + int a:4; + int b:4; +}; + +template<typename T> +concept c1 + = requires(T x, void(f)(int &)) { f(x.a); }; // { dg-bogus "cannot bind" } + +static_assert(!c1<B>);