Index: cp/typeck.c =================================================================== --- cp/typeck.c (revision 220366) +++ cp/typeck.c (working copy) @@ -4552,35 +4552,44 @@ cp_build_binary_op (location_t location, The reason for the `!op0.pfn' bit is that a NULL pointer-to-member is any member with a zero PFN and - LSB of the DELTA field is 0. */ + LSB of the DELTA field is 0. Note: avoid generating the + '|| (!op0.pfn && ...)' if !op0.pfn is known to be false. */ - e1 = cp_build_binary_op (location, BIT_AND_EXPR, - delta0, - integer_one_node, - complain); - e1 = cp_build_binary_op (location, - EQ_EXPR, e1, integer_zero_node, - complain); - e2 = cp_build_binary_op (location, BIT_AND_EXPR, - delta1, - integer_one_node, - complain); - e2 = cp_build_binary_op (location, - EQ_EXPR, e2, integer_zero_node, - complain); - e1 = cp_build_binary_op (location, - TRUTH_ANDIF_EXPR, e2, e1, - complain); - e2 = cp_build_binary_op (location, EQ_EXPR, - pfn0, - build_zero_cst (TREE_TYPE (pfn0)), - complain); - e2 = cp_build_binary_op (location, - TRUTH_ANDIF_EXPR, e2, e1, complain); - e1 = cp_build_binary_op (location, - EQ_EXPR, delta0, delta1, complain); - e1 = cp_build_binary_op (location, - TRUTH_ORIF_EXPR, e1, e2, complain); + if (TREE_CODE (pfn0) != ADDR_EXPR + || !decl_with_nonnull_addr_p (TREE_OPERAND (pfn0, 0))) + { + e1 = cp_build_binary_op (location, BIT_AND_EXPR, + delta0, + integer_one_node, + complain); + e1 = cp_build_binary_op (location, + EQ_EXPR, e1, integer_zero_node, + complain); + e2 = cp_build_binary_op (location, BIT_AND_EXPR, + delta1, + integer_one_node, + complain); + e2 = cp_build_binary_op (location, + EQ_EXPR, e2, integer_zero_node, + complain); + e1 = cp_build_binary_op (location, + TRUTH_ANDIF_EXPR, e2, e1, + complain); + e2 = cp_build_binary_op (location, EQ_EXPR, + pfn0, + build_zero_cst (TREE_TYPE (pfn0)), + complain); + e2 = cp_build_binary_op (location, + TRUTH_ANDIF_EXPR, e2, e1, complain); + e1 = cp_build_binary_op (location, + EQ_EXPR, delta0, delta1, complain); + e1 = cp_build_binary_op (location, + TRUTH_ORIF_EXPR, e1, e2, complain); + + } + else + e1 = cp_build_binary_op (location, + EQ_EXPR, delta0, delta1, complain); } else { @@ -4591,17 +4600,22 @@ cp_build_binary_op (location_t location, The reason for the `!op0.pfn' bit is that a NULL pointer-to-member is any member with a zero PFN; the - DELTA field is unspecified. */ + DELTA field is unspecified. Note: avoid generating the + '!op0.pfn ||' if !op0.pfn is known to be false. */ e1 = cp_build_binary_op (location, EQ_EXPR, delta0, delta1, complain); - e2 = cp_build_binary_op (location, - EQ_EXPR, - pfn0, - build_zero_cst (TREE_TYPE (pfn0)), - complain); - e1 = cp_build_binary_op (location, - TRUTH_ORIF_EXPR, e1, e2, complain); + if (TREE_CODE (pfn0) != ADDR_EXPR + || !decl_with_nonnull_addr_p (TREE_OPERAND (pfn0, 0))) + { + e2 = cp_build_binary_op (location, + EQ_EXPR, + pfn0, + build_zero_cst (TREE_TYPE (pfn0)), + complain); + e1 = cp_build_binary_op (location, + TRUTH_ORIF_EXPR, e1, e2, complain); + } } e2 = build2 (EQ_EXPR, boolean_type_node, pfn0, pfn1); e = cp_build_binary_op (location, Index: testsuite/g++.dg/warn/Waddress-2.C =================================================================== --- testsuite/g++.dg/warn/Waddress-2.C (revision 0) +++ testsuite/g++.dg/warn/Waddress-2.C (working copy) @@ -0,0 +1,24 @@ +// PR c++/64877 +// { dg-options "-Waddress" } + +template +struct S +{ + void m() { + } + + S() + { + if (&S::Unwrap != &Derived::Unwrap) + m(); + } + + void Unwrap() { + } +}; + +struct T : public S +{ +}; + +T t;