From 1e099144a514d5b6211f5537471b6390f7771627 Mon Sep 17 00:00:00 2001 From: Mark Mitchell Date: Thu, 10 Apr 2003 19:28:46 +0000 Subject: [PATCH] class.c (layout_class_type): Correct handling for overlong bit-fields whose width is the same as an integer type. * class.c (layout_class_type): Correct handling for overlong bit-fields whose width is the same as an integer type. * g++.dg/abi/bitfield10.C: New test. From-SVN: r65432 --- gcc/cp/ChangeLog | 5 +++++ gcc/cp/class.c | 36 +++++++++++++++++++++-------------- gcc/testsuite/ChangeLog | 4 ++++ gcc/testsuite/g++.dg/abi/bitfield10.C | 5 +++++ 4 files changed, 36 insertions(+), 14 deletions(-) create mode 100644 gcc/testsuite/g++.dg/abi/bitfield10.C diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog index 8311500..3e3e4f3 100644 --- a/gcc/cp/ChangeLog +++ b/gcc/cp/ChangeLog @@ -1,3 +1,8 @@ +2003-04-10 Mark Mitchell + + * class.c (layout_class_type): Correct handling for overlong + bit-fields whose width is the same as an integer type. + 2003-04-06 Zack Weinberg * cp-tree.def: Make fourth element for all 'c' and 'x' nodes zero. diff --git a/gcc/cp/class.c b/gcc/cp/class.c index e6fad0a..ed0824a 100644 --- a/gcc/cp/class.c +++ b/gcc/cp/class.c @@ -4819,6 +4819,8 @@ layout_class_type (tree t, tree *virtuals_p) } type = TREE_TYPE (field); + + padding = NULL_TREE; /* If this field is a bit-field whose width is greater than its type, then there are some special rules for allocating @@ -4842,19 +4844,26 @@ layout_class_type (tree t, tree *virtuals_p) type that fits. */ integer_type = integer_types[itk - 1]; - if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE) - /* In a union, the padding field must have the full width - of the bit-field; all fields start at offset zero. */ - padding = DECL_SIZE (field); - else + /* Figure out how much additional padding is required. GCC + 3.2 always created a padding field, even if it had zero + width. */ + if (!abi_version_at_least (2) + || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field))) { - if (warn_abi && TREE_CODE (t) == UNION_TYPE) - warning ("size assigned to `%T' may not be " - "ABI-compliant and may change in a future " - "version of GCC", - t); - padding = size_binop (MINUS_EXPR, DECL_SIZE (field), - TYPE_SIZE (integer_type)); + if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE) + /* In a union, the padding field must have the full width + of the bit-field; all fields start at offset zero. */ + padding = DECL_SIZE (field); + else + { + if (warn_abi && TREE_CODE (t) == UNION_TYPE) + warning ("size assigned to `%T' may not be " + "ABI-compliant and may change in a future " + "version of GCC", + t); + padding = size_binop (MINUS_EXPR, DECL_SIZE (field), + TYPE_SIZE (integer_type)); + } } #ifdef PCC_BITFIELD_TYPE_MATTERS /* An unnamed bitfield does not normally affect the @@ -4873,8 +4882,6 @@ layout_class_type (tree t, tree *virtuals_p) DECL_ALIGN (field) = TYPE_ALIGN (integer_type); DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type); } - else - padding = NULL_TREE; layout_nonempty_base_or_field (rli, field, NULL_TREE, empty_base_offsets); @@ -4924,6 +4931,7 @@ layout_class_type (tree t, tree *virtuals_p) char_type_node); DECL_BIT_FIELD (padding_field) = 1; DECL_SIZE (padding_field) = padding; + DECL_CONTEXT (padding_field) = t; layout_nonempty_base_or_field (rli, padding_field, NULL_TREE, empty_base_offsets); diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index dfddab2..52be21c 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2003-04-10 Mark Mitchell + + * g++.dg/abi/bitfield10.C: New test. + 2003-04-09 Mike Stump * gcc.dg/pch/pch.exp: Make testcase names longer. diff --git a/gcc/testsuite/g++.dg/abi/bitfield10.C b/gcc/testsuite/g++.dg/abi/bitfield10.C new file mode 100644 index 0000000..df40fa3 --- /dev/null +++ b/gcc/testsuite/g++.dg/abi/bitfield10.C @@ -0,0 +1,5 @@ +// { dg-options "-w" } + +struct S { + int i : 64; +}; -- 2.7.4