Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look
OK for trunk?
-- >8 --
As a follow-up to r15-3741-gee3efe06c9c49c, which was only concerned
with usings, it seems we should also compare contexts of a reversed
vs non-reversed (member) candidate during operator overload
resolution.
DR 2789
gcc/cp/ChangeLog:
* call.cc (cand_parms_match): Check for matching class contexts
even in the reversed case.
gcc/testsuite/ChangeLog:
* g++.dg/cpp2a/concepts-memfun4.C: Adjust expected result
involving reversed candidate.
---
gcc/cp/call.cc | 11 +++++++----
gcc/testsuite/g++.dg/cpp2a/concepts-memfun4.C | 6 +++---
2 files changed, 10 insertions(+), 7 deletions(-)
diff --git a/gcc/cp/call.cc b/gcc/cp/call.cc
index f2ce50857ec..70783baac24 100644
--- a/gcc/cp/call.cc
+++ b/gcc/cp/call.cc
@@ -12865,10 +12865,6 @@ cand_parms_match (z_candidate *c1, z_candidate *c2,
pmatch match_kind)
}
}
- else if (reversed)
- return (reversed_match (c1, c2)
- && reversed_match (c2, c1));
-
tree parms1 = TYPE_ARG_TYPES (TREE_TYPE (fn1));
tree parms2 = TYPE_ARG_TYPES (TREE_TYPE (fn2));
@@ -12880,6 +12876,10 @@ cand_parms_match (z_candidate *c1, z_candidate *c2,
pmatch match_kind)
if (base1 != base2)
return false;
+ if (reversed)
+ return (reversed_match (c1, c2)
+ && reversed_match (c2, c1));
+
/* Use object_parms_correspond to simplify comparing iobj/xobj/static
member functions. */
if (!object_parms_correspond (fn1, fn2, base1))
@@ -12897,6 +12897,9 @@ cand_parms_match (z_candidate *c1, z_candidate *c2,
pmatch match_kind)
parms1 = skip_parms (fn1, parms1);
parms2 = skip_parms (fn2, parms2);
}
+ else if (reversed)
+ return (reversed_match (c1, c2)
+ && reversed_match (c2, c1));
return compparms (parms1, parms2);
}
diff --git a/gcc/testsuite/g++.dg/cpp2a/concepts-memfun4.C
b/gcc/testsuite/g++.dg/cpp2a/concepts-memfun4.C
index cf7f13c007d..d849e9129a3 100644
--- a/gcc/testsuite/g++.dg/cpp2a/concepts-memfun4.C
+++ b/gcc/testsuite/g++.dg/cpp2a/concepts-memfun4.C
@@ -91,7 +91,7 @@ namespace N1 {
A<> a;
B<> b;
- // when comparing the A op== to the reversed B op==, we compare them in
- // reverse order, so they match, and we choose the more constrained.
- static_assert (a == b);
+ // A op== and B op== are defined in different classes so constraints
+ // aren't considered, and the tie is broken via reversedness.
+ static_assert (!(a == b));
}
--
2.46.1.565.g6531f31ef3
