gcc/c/ChangeLog: * c-decl.cc (finish_struct): Change errors to pedwarns for the cases flexible array members in union or alone in structures.
gcc/cp/ChangeLog: * class.cc (diagnose_flexarrays): Change error to pdewarn for the case flexible array members alone in structures. * decl.cc (grokdeclarator): Change error to pdewarn for the case flexible array members in unions. gcc/ChangeLog: * stor-layout.cc (place_union_field): Use zero sizes for flexible array member fields. --- gcc/c/c-decl.cc | 16 +++++----------- gcc/cp/class.cc | 11 ++++++++--- gcc/cp/decl.cc | 7 +++---- gcc/stor-layout.cc | 9 +++++++-- 4 files changed, 23 insertions(+), 20 deletions(-) diff --git a/gcc/c/c-decl.cc b/gcc/c/c-decl.cc index 345090dae38b..947f3cd589eb 100644 --- a/gcc/c/c-decl.cc +++ b/gcc/c/c-decl.cc @@ -9471,11 +9471,8 @@ finish_struct (location_t loc, tree t, tree fieldlist, tree attributes, if (flexible_array_member_type_p (TREE_TYPE (x))) { if (TREE_CODE (t) == UNION_TYPE) - { - error_at (DECL_SOURCE_LOCATION (x), - "flexible array member in union"); - TREE_TYPE (x) = error_mark_node; - } + pedwarn (DECL_SOURCE_LOCATION (x), OPT_Wpedantic, + "flexible array member in union is a GCC extension"); else if (!is_last_field) { error_at (DECL_SOURCE_LOCATION (x), @@ -9483,12 +9480,9 @@ finish_struct (location_t loc, tree t, tree fieldlist, tree attributes, TREE_TYPE (x) = error_mark_node; } else if (!saw_named_field) - { - error_at (DECL_SOURCE_LOCATION (x), - "flexible array member in a struct with no named " - "members"); - TREE_TYPE (x) = error_mark_node; - } + pedwarn (DECL_SOURCE_LOCATION (x), OPT_Wpedantic, + "flexible array member in a struct with no named " + "members is a GCC extension"); } if (pedantic && TREE_CODE (t) == RECORD_TYPE diff --git a/gcc/cp/class.cc b/gcc/cp/class.cc index 5f258729940b..0c8afb72550f 100644 --- a/gcc/cp/class.cc +++ b/gcc/cp/class.cc @@ -7624,6 +7624,7 @@ diagnose_flexarrays (tree t, const flexmems_t *fmem) bool diagd = false; const char *msg = 0; + const char *msg_fam = 0; if (TYPE_DOMAIN (TREE_TYPE (fmem->array))) { @@ -7649,15 +7650,19 @@ diagnose_flexarrays (tree t, const flexmems_t *fmem) if (fmem->after[0]) msg = G_("flexible array member %qD not at end of %q#T"); else if (!fmem->first) - msg = G_("flexible array member %qD in an otherwise empty %q#T"); + msg_fam = G_("flexible array member %qD in an otherwise" + " empty %q#T is a GCC extension"); - if (msg) + if (msg || msg_fam) { location_t loc = DECL_SOURCE_LOCATION (fmem->array); diagd = true; auto_diagnostic_group d; - error_at (loc, msg, fmem->array, t); + if (msg) + error_at (loc, msg, fmem->array, t); + else + pedwarn (loc, OPT_Wpedantic, msg_fam, fmem->array, t); /* In the unlikely event that the member following the flexible array member is declared in a different class, or the member diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc index 65ab64885ff8..9a91c6f80da1 100644 --- a/gcc/cp/decl.cc +++ b/gcc/cp/decl.cc @@ -14566,10 +14566,9 @@ grokdeclarator (const cp_declarator *declarator, if (ctype && (TREE_CODE (ctype) == UNION_TYPE || TREE_CODE (ctype) == QUAL_UNION_TYPE)) - { - error_at (id_loc, "flexible array member in union"); - type = error_mark_node; - } + pedwarn (id_loc, OPT_Wpedantic, + "flexible array member in union is a GCC extension"); + else { /* Array is a flexible member. */ diff --git a/gcc/stor-layout.cc b/gcc/stor-layout.cc index e34be19689c0..10c0809914cd 100644 --- a/gcc/stor-layout.cc +++ b/gcc/stor-layout.cc @@ -1245,13 +1245,18 @@ place_union_field (record_layout_info rli, tree field) && TYPE_TYPELESS_STORAGE (TREE_TYPE (field))) TYPE_TYPELESS_STORAGE (rli->t) = 1; + /* We might see a flexible array member field (with no DECL_SIZE_UNIT), use + zero size for such field. */ + tree field_size_unit = DECL_SIZE_UNIT (field) + ? DECL_SIZE_UNIT (field) + : build_int_cst (sizetype, 0); /* We assume the union's size will be a multiple of a byte so we don't bother with BITPOS. */ if (TREE_CODE (rli->t) == UNION_TYPE) - rli->offset = size_binop (MAX_EXPR, rli->offset, DECL_SIZE_UNIT (field)); + rli->offset = size_binop (MAX_EXPR, rli->offset, field_size_unit); else if (TREE_CODE (rli->t) == QUAL_UNION_TYPE) rli->offset = fold_build3 (COND_EXPR, sizetype, DECL_QUALIFIER (field), - DECL_SIZE_UNIT (field), rli->offset); + field_size_unit, rli->offset); } /* A bitfield of SIZE with a required access alignment of ALIGN is allocated -- 2.31.1