From: Jakub Jelinek Date: Thu, 19 Jan 2023 22:31:15 +0000 (+0100) Subject: c++: Fix up handling of non-dependent subscript with static operator[] [PR108437] X-Git-Tag: basepoints/gcc-14~1941 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=86caab6c5d1e26e1c54c3dceacc873d6e27bfc09;p=thirdparty%2Fgcc.git c++: Fix up handling of non-dependent subscript with static operator[] [PR108437] As the following testcases shows, when adding static operator[] support I've missed that the 2 build_min_non_dep_op_overload functions need to be adjusted. The first one we only use for the single index case, but as cp_tree_code_length (ARRAY_REF) is 2, we were running into an assertion there which compared nargs and expected_nargs. For ARRAY_REF, the operator[] is either a non-static member or newly static member, never out of class and for the static member case if user uses single index the operator[] needs to have a single argument as well, but the function is called with 2 - the object it is invoked on and the index. We need to evaluate side-effects of the object and use just a single argument in the call - the index. The other build_min_non_dep_op_overload overload has been added solely for ARRAY_REF - CALL_EXPR is the other operator that accepts variable number of operands but that one goes through different routines. There we asserted it is a METHOD_TYPE, so again we shouldn't assert that but handle the case when it is not one by making sure object's side-effects are evaluated if needed and passing all the index arguments to the static operator[]. 2023-01-19 Jakub Jelinek PR c++/108437 * cp-tree.h (keep_unused_object_arg): Declare. * call.cc (keep_unused_object_arg): No longer static. * tree.cc (build_min_non_dep_op_overload): Handle ARRAY_REF with overload being static member function. * g++.dg/cpp23/subscript12.C: New test. * g++.dg/cpp23/subscript13.C: New test. --- diff --git a/gcc/cp/call.cc b/gcc/cp/call.cc index 0780b5840a34..991730713e6b 100644 --- a/gcc/cp/call.cc +++ b/gcc/cp/call.cc @@ -5187,7 +5187,7 @@ build_operator_new_call (tree fnname, vec **args, or static operator(), in which cases the source expression would be `obj[...]' or `obj(...)'. */ -static tree +tree keep_unused_object_arg (tree result, tree obj, tree fn) { if (result == NULL_TREE diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h index d3058c093e12..9f188724cf2f 100644 --- a/gcc/cp/cp-tree.h +++ b/gcc/cp/cp-tree.h @@ -6599,6 +6599,7 @@ inline tree build_new_op (const op_location_t &loc, enum tree_code code, return build_new_op (loc, code, flags, arg1, arg2, NULL_TREE, NULL_TREE, NULL, complain); } +extern tree keep_unused_object_arg (tree, tree, tree); extern tree build_op_call (tree, vec **, tsubst_flags_t); extern tree build_op_subscript (const op_location_t &, tree, diff --git a/gcc/cp/tree.cc b/gcc/cp/tree.cc index 8060d39d216c..c1da868732b2 100644 --- a/gcc/cp/tree.cc +++ b/gcc/cp/tree.cc @@ -3693,14 +3693,20 @@ build_min_non_dep_op_overload (enum tree_code op, { va_list p; int nargs, expected_nargs; - tree fn, call; + tree fn, call, obj = NULL_TREE; non_dep = extract_call_expr (non_dep); nargs = call_expr_nargs (non_dep); expected_nargs = cp_tree_code_length (op); - if (TREE_CODE (TREE_TYPE (overload)) == METHOD_TYPE) + if (TREE_CODE (TREE_TYPE (overload)) == METHOD_TYPE + /* For ARRAY_REF, operator[] is either a non-static member or newly + static member, never out of class and for the static member case + if user uses single index the operator[] needs to have a single + argument as well, but the function is called with 2 - the object + it is invoked on and the index. */ + || op == ARRAY_REF) expected_nargs -= 1; if ((op == POSTINCREMENT_EXPR || op == POSTDECREMENT_EXPR) @@ -3715,6 +3721,8 @@ build_min_non_dep_op_overload (enum tree_code op, if (TREE_CODE (TREE_TYPE (overload)) == FUNCTION_TYPE) { fn = overload; + if (op == ARRAY_REF) + obj = va_arg (p, tree); for (int i = 0; i < nargs; i++) { tree arg = va_arg (p, tree); @@ -3746,6 +3754,8 @@ build_min_non_dep_op_overload (enum tree_code op, CALL_EXPR_ORDERED_ARGS (call_expr) = CALL_EXPR_ORDERED_ARGS (non_dep); CALL_EXPR_REVERSE_ARGS (call_expr) = CALL_EXPR_REVERSE_ARGS (non_dep); + if (obj) + return keep_unused_object_arg (call, obj, overload); return call; } @@ -3759,11 +3769,15 @@ build_min_non_dep_op_overload (tree non_dep, tree overload, tree object, non_dep = extract_call_expr (non_dep); unsigned int nargs = call_expr_nargs (non_dep); - gcc_assert (TREE_CODE (TREE_TYPE (overload)) == METHOD_TYPE); - tree binfo = TYPE_BINFO (TREE_TYPE (object)); - tree method = build_baselink (binfo, binfo, overload, NULL_TREE); - tree fn = build_min (COMPONENT_REF, TREE_TYPE (overload), - object, method, NULL_TREE); + tree fn = overload; + if (TREE_CODE (TREE_TYPE (overload)) == METHOD_TYPE) + { + tree binfo = TYPE_BINFO (TREE_TYPE (object)); + tree method = build_baselink (binfo, binfo, overload, NULL_TREE); + fn = build_min (COMPONENT_REF, TREE_TYPE (overload), + object, method, NULL_TREE); + object = NULL_TREE; + } gcc_assert (vec_safe_length (args) == nargs); tree call = build_min_non_dep_call_vec (non_dep, fn, args); @@ -3774,6 +3788,8 @@ build_min_non_dep_op_overload (tree non_dep, tree overload, tree object, CALL_EXPR_ORDERED_ARGS (call_expr) = CALL_EXPR_ORDERED_ARGS (non_dep); CALL_EXPR_REVERSE_ARGS (call_expr) = CALL_EXPR_REVERSE_ARGS (non_dep); + if (object) + return keep_unused_object_arg (call, object, overload); return call; } diff --git a/gcc/testsuite/g++.dg/cpp23/subscript12.C b/gcc/testsuite/g++.dg/cpp23/subscript12.C new file mode 100644 index 000000000000..49cd8a6ac5b0 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp23/subscript12.C @@ -0,0 +1,34 @@ +// PR c++/108437 +// { dg-do run { target c++23 } } + +struct S { static int &operator[] (int x) { static int a[2]; return a[x]; } }; +struct U { static int &operator[] (int x, int y, int z) { static int a[2]; return a[x + y + z]; } }; +struct V { static int &operator[] () { static int a; return a; } }; + +template void +foo () +{ + S s; + s[0]++; + T t; + t[0]++; + U u; + u[0, 0, 0]++; + V v; + v[]++; + W w; + w[0, 0, 0]++; + X x; + x[]++; +} + +int +main () +{ + S::operator[] (0) = 1; + U::operator[] (0, 0, 0) = 2; + V::operator[] () = 3; + foo (); + if (S::operator[] (0) != 3 || U::operator[] (0, 0, 0) != 4 || V::operator[] () != 5) + __builtin_abort (); +} diff --git a/gcc/testsuite/g++.dg/cpp23/subscript13.C b/gcc/testsuite/g++.dg/cpp23/subscript13.C new file mode 100644 index 000000000000..3fb3b4975b18 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp23/subscript13.C @@ -0,0 +1,43 @@ +// PR c++/108437 +// { dg-do run { target c++23 } } + +struct S { static int &operator[] (int x) { static int a[2]; return a[x]; } }; +struct U { static int &operator[] (int x, int y, int z) { static int a[2]; return a[x + y + z]; } }; +struct V { static int &operator[] () { static int a; return a; } }; +int cnt; + +template +T & +bar (T &x) +{ + ++cnt; + return x; +} + +template void +foo () +{ + S s; + bar (s)[0]++; + T t; + bar (t)[0]++; + U u; + bar (u)[0, 0, 0]++; + V v; + bar (v)[]++; + W w; + bar (w)[0, 0, 0]++; + X x; + bar (x)[]++; +} + +int +main () +{ + S::operator[] (0) = 1; + U::operator[] (0, 0, 0) = 2; + V::operator[] () = 3; + foo (); + if (S::operator[] (0) != 3 || U::operator[] (0, 0, 0) != 4 || V::operator[] () != 5 || cnt != 6) + __builtin_abort (); +}