From 79e7b1fe3290f351f178dafee4b3df4ece61ba9c Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Thu, 10 May 2018 19:40:28 +0200 Subject: [PATCH] re PR c++/85662 ("error: non-constant condition for static assertion" from __builtin_offsetof in C++) PR c++/85662 * c-common.h (fold_offsetof_1): Removed. (fold_offsetof): Add TYPE argument defaulted to size_type_node and CTX argument defaulted to ERROR_MARK. * c-common.c (fold_offsetof_1): Renamed to ... (fold_offsetof): ... this. Remove wrapper function. Add TYPE argument, convert the pointer constant to TYPE and use size_binop with PLUS_EXPR instead of fold_build_pointer_plus if type is not a pointer type. Adjust recursive calls. * c-fold.c (c_fully_fold_internal): Use fold_offsetof rather than fold_offsetof_1, pass TREE_TYPE (expr) as TYPE to it and drop the fold_convert_loc. * c-typeck.c (build_unary_op): Use fold_offsetof rather than fold_offsetof_1, pass argtype as TYPE to it and drop the fold_convert_loc. * cp-gimplify.c (cp_fold): Use fold_offsetof rather than fold_offsetof_1, pass TREE_TYPE (x) as TYPE to it and drop the fold_convert. * g++.dg/ext/offsetof2.C: New test. From-SVN: r260119 --- gcc/c-family/ChangeLog | 12 ++++++++++++ gcc/c-family/c-common.c | 24 +++++++++--------------- gcc/c-family/c-common.h | 4 ++-- gcc/c/ChangeLog | 10 ++++++++++ gcc/c/c-fold.c | 2 +- gcc/c/c-typeck.c | 2 +- gcc/cp/ChangeLog | 7 +++++++ gcc/cp/cp-gimplify.c | 2 +- gcc/testsuite/ChangeLog | 5 +++++ gcc/testsuite/g++.dg/ext/offsetof2.C | 6 ++++++ 10 files changed, 54 insertions(+), 20 deletions(-) create mode 100644 gcc/testsuite/g++.dg/ext/offsetof2.C diff --git a/gcc/c-family/ChangeLog b/gcc/c-family/ChangeLog index 6ea5eaf1fdf..052b2226588 100644 --- a/gcc/c-family/ChangeLog +++ b/gcc/c-family/ChangeLog @@ -1,3 +1,15 @@ +2018-05-10 Jakub Jelinek + + PR c++/85662 + * c-common.h (fold_offsetof_1): Removed. + (fold_offsetof): Add TYPE argument defaulted to size_type_node and + CTX argument defaulted to ERROR_MARK. + * c-common.c (fold_offsetof_1): Renamed to ... + (fold_offsetof): ... this. Remove wrapper function. Add TYPE + argument, convert the pointer constant to TYPE and use size_binop + with PLUS_EXPR instead of fold_build_pointer_plus if type is not + a pointer type. Adjust recursive calls. + 2018-05-10 Eric Botcazou PR c++/85400 diff --git a/gcc/c-family/c-common.c b/gcc/c-family/c-common.c index 7e6905e791e..e8bb3eb23f8 100644 --- a/gcc/c-family/c-common.c +++ b/gcc/c-family/c-common.c @@ -6168,10 +6168,11 @@ c_common_to_target_charset (HOST_WIDE_INT c) /* Fold an offsetof-like expression. EXPR is a nested sequence of component references with an INDIRECT_REF of a constant at the bottom; much like the - traditional rendering of offsetof as a macro. Return the folded result. */ + traditional rendering of offsetof as a macro. TYPE is the desired type of + the whole expression. Return the folded result. */ tree -fold_offsetof_1 (tree expr, enum tree_code ctx) +fold_offsetof (tree expr, tree type, enum tree_code ctx) { tree base, off, t; tree_code code = TREE_CODE (expr); @@ -6196,10 +6197,10 @@ fold_offsetof_1 (tree expr, enum tree_code ctx) error ("cannot apply % to a non constant address"); return error_mark_node; } - return TREE_OPERAND (expr, 0); + return convert (type, TREE_OPERAND (expr, 0)); case COMPONENT_REF: - base = fold_offsetof_1 (TREE_OPERAND (expr, 0), code); + base = fold_offsetof (TREE_OPERAND (expr, 0), type, code); if (base == error_mark_node) return base; @@ -6216,7 +6217,7 @@ fold_offsetof_1 (tree expr, enum tree_code ctx) break; case ARRAY_REF: - base = fold_offsetof_1 (TREE_OPERAND (expr, 0), code); + base = fold_offsetof (TREE_OPERAND (expr, 0), type, code); if (base == error_mark_node) return base; @@ -6273,23 +6274,16 @@ fold_offsetof_1 (tree expr, enum tree_code ctx) /* Handle static members of volatile structs. */ t = TREE_OPERAND (expr, 1); gcc_checking_assert (VAR_P (get_base_address (t))); - return fold_offsetof_1 (t); + return fold_offsetof (t, type); default: gcc_unreachable (); } + if (!POINTER_TYPE_P (type)) + return size_binop (PLUS_EXPR, base, convert (type, off)); return fold_build_pointer_plus (base, off); } - -/* Likewise, but convert it to the return type of offsetof. */ - -tree -fold_offsetof (tree expr) -{ - return convert (size_type_node, fold_offsetof_1 (expr)); -} - /* *PTYPE is an incomplete array. Complete it with a domain based on INITIAL_VALUE. If INITIAL_VALUE is not present, use 1 if DO_DEFAULT diff --git a/gcc/c-family/c-common.h b/gcc/c-family/c-common.h index 6cf7614f682..f2c66628e53 100644 --- a/gcc/c-family/c-common.h +++ b/gcc/c-family/c-common.h @@ -1033,8 +1033,8 @@ extern bool c_dump_tree (void *, tree); extern void verify_sequence_points (tree); -extern tree fold_offsetof_1 (tree, tree_code ctx = ERROR_MARK); -extern tree fold_offsetof (tree); +extern tree fold_offsetof (tree, tree = size_type_node, + tree_code ctx = ERROR_MARK); extern int complete_array_type (tree *, tree, bool); diff --git a/gcc/c/ChangeLog b/gcc/c/ChangeLog index d88d70d99fc..a8e21284deb 100644 --- a/gcc/c/ChangeLog +++ b/gcc/c/ChangeLog @@ -1,3 +1,13 @@ +2018-05-10 Jakub Jelinek + + PR c++/85662 + * c-fold.c (c_fully_fold_internal): Use fold_offsetof rather than + fold_offsetof_1, pass TREE_TYPE (expr) as TYPE to it and drop the + fold_convert_loc. + * c-typeck.c (build_unary_op): Use fold_offsetof rather than + fold_offsetof_1, pass argtype as TYPE to it and drop the + fold_convert_loc. + 2018-05-02 David Pagan PR c/30552 diff --git a/gcc/c/c-fold.c b/gcc/c/c-fold.c index 480e34ce4f4..d276e635a28 100644 --- a/gcc/c/c-fold.c +++ b/gcc/c/c-fold.c @@ -473,7 +473,7 @@ c_fully_fold_internal (tree expr, bool in_init, bool *maybe_const_operands, && (op1 = get_base_address (op0)) != NULL_TREE && INDIRECT_REF_P (op1) && TREE_CONSTANT (TREE_OPERAND (op1, 0))) - ret = fold_convert_loc (loc, TREE_TYPE (expr), fold_offsetof_1 (op0)); + ret = fold_offsetof (op0, TREE_TYPE (expr)); else if (op0 != orig_op0 || in_init) ret = in_init ? fold_build1_initializer_loc (loc, code, TREE_TYPE (expr), op0) diff --git a/gcc/c/c-typeck.c b/gcc/c/c-typeck.c index 5b3ea28af06..45a4529ed52 100644 --- a/gcc/c/c-typeck.c +++ b/gcc/c/c-typeck.c @@ -4676,7 +4676,7 @@ build_unary_op (location_t location, enum tree_code code, tree xarg, if (val && INDIRECT_REF_P (val) && TREE_CONSTANT (TREE_OPERAND (val, 0))) { - ret = fold_convert_loc (location, argtype, fold_offsetof_1 (arg)); + ret = fold_offsetof (arg, argtype); goto return_build_unary_op; } diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog index a2de8f68125..e21afc7e09a 100644 --- a/gcc/cp/ChangeLog +++ b/gcc/cp/ChangeLog @@ -1,3 +1,10 @@ +2018-05-10 Jakub Jelinek + + PR c++/85662 + * cp-gimplify.c (cp_fold): Use fold_offsetof rather than + fold_offsetof_1, pass TREE_TYPE (x) as TYPE to it and drop the + fold_convert. + 2018-05-10 Eric Botcazou PR c++/85400 diff --git a/gcc/cp/cp-gimplify.c b/gcc/cp/cp-gimplify.c index 74490654631..84882f8dbb7 100644 --- a/gcc/cp/cp-gimplify.c +++ b/gcc/cp/cp-gimplify.c @@ -2232,7 +2232,7 @@ cp_fold (tree x) val = TREE_OPERAND (val, 0); STRIP_NOPS (val); if (TREE_CODE (val) == INTEGER_CST) - return fold_convert (TREE_TYPE (x), fold_offsetof_1 (op0)); + return fold_offsetof (op0, TREE_TYPE (x)); } } goto finish_unary; diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 694857b218c..89f64404b3f 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2018-05-10 Jakub Jelinek + + PR c++/85662 + * g++.dg/ext/offsetof2.C: New test. + 2018-05-10 Paul Thomas PR fortran/68846 diff --git a/gcc/testsuite/g++.dg/ext/offsetof2.C b/gcc/testsuite/g++.dg/ext/offsetof2.C new file mode 100644 index 00000000000..647cf8d0b77 --- /dev/null +++ b/gcc/testsuite/g++.dg/ext/offsetof2.C @@ -0,0 +1,6 @@ +// PR c++/85662 +// { dg-do compile { target c++11 } } + +struct S { unsigned long x[31]; }; +struct T { bool b; S f; }; +static_assert (__builtin_offsetof (T, f.x[31 - 1]) == __builtin_offsetof (T, f.x[30]), ""); -- 2.30.2