From 2f33032a93f24ccc0c0d2f23e2a3ec0442f638d4 Mon Sep 17 00:00:00 2001 From: Keith Seitz Date: Thu, 11 Jun 2020 14:34:44 +0200 Subject: Compute proper length for dynamic types of TYPE_CODE_TYPEDEF This patch fixes gdb/21356 in which we hit an assertion in value_contents_bits_eq: (gdb) p container_object2 (gdb) p container_object2 $1 = {_container_member2 = 15, _vla_struct_object2 = {_some_member = 0, _vla_field = { ../../src/gdb/value.c:829: internal-error: \ int value_contents_bits_eq(const value*, int, const value*, int, int): \ Assertion `offset1 + length \ <= TYPE_LENGTH (val1->enclosing_type) * TARGET_CHAR_BIT' failed. This is happening because TYPE_LENGTH (val1->enclosing_type) is erroneously based on enclosing_type, which is a typedef, instead of the actual underlying type. This can be traced back to resolve_dynamic_struct, where the size of the type is computed: ... TYPE_FIELD_TYPE (resolved_type, i) = resolve_dynamic_type_internal (TYPE_FIELD_TYPE (resolved_type, i), &pinfo, 0); gdb_assert (TYPE_FIELD_LOC_KIND (resolved_type, i) == FIELD_LOC_KIND_BITPOS); new_bit_length = TYPE_FIELD_BITPOS (resolved_type, i); if (TYPE_FIELD_BITSIZE (resolved_type, i) != 0) new_bit_length += TYPE_FIELD_BITSIZE (resolved_type, i); else new_bit_length += (TYPE_LENGTH (TYPE_FIELD_TYPE (resolved_type, i)) * TARGET_CHAR_BIT); ... In this function, resolved_type is TYPE_CODE_TYPEDEF which is not what we want to use to calculate the size of the actual field. This patch fixes this and the similar problem in resolve_dynamic_union. gdb/ChangeLog: 2020-06-11 Keith Seitz PR gdb/21356 * gdbtypes.c (resolve_dynamic_union, resolve_dynamic_struct): Resolve typedefs for type length calculations. gdb/testsuite/ChangeLog: 2020-06-11 Keith Seitz PR gdb/21356 * gdb.base/vla-datatypes.c (vla_factory): Add typedef for struct vla_struct. Add new struct vla_typedef and union vla_typedef_union and corresponding instantiation objects. Initialize new objects. * gdb.base/vla-datatypes.exp: Add tests for vla_typedef_struct_object and vla_typedef_union_object. Fixup type for vla_struct_object. --- gdb/ChangeLog | 6 ++++++ gdb/gdbtypes.c | 14 ++++++++++---- gdb/testsuite/ChangeLog | 12 ++++++++++++ gdb/testsuite/gdb.base/vla-datatypes.c | 28 +++++++++++++++++++++++++++- gdb/testsuite/gdb.base/vla-datatypes.exp | 6 +++++- 5 files changed, 60 insertions(+), 6 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index e009aabc8a8..e006943e493 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,9 @@ +2020-06-11 Keith Seitz + + PR gdb/21356 + * gdbtypes.c (resolve_dynamic_union, resolve_dynamic_struct): + Resolve typedefs for type length calculations. + 2020-06-10 Tom de Vries PR ada/24713 diff --git a/gdb/gdbtypes.c b/gdb/gdbtypes.c index b5a13107ede..cdf88a4a7d1 100644 --- a/gdb/gdbtypes.c +++ b/gdb/gdbtypes.c @@ -2264,8 +2264,10 @@ resolve_dynamic_union (struct type *type, t = resolve_dynamic_type_internal (resolved_type->field (i).type (), addr_stack, 0); resolved_type->field (i).set_type (t); - if (TYPE_LENGTH (t) > max_len) - max_len = TYPE_LENGTH (t); + + struct type *real_type = check_typedef (t); + if (TYPE_LENGTH (real_type) > max_len) + max_len = TYPE_LENGTH (real_type); } TYPE_LENGTH (resolved_type) = max_len; @@ -2521,8 +2523,12 @@ resolve_dynamic_struct (struct type *type, if (TYPE_FIELD_BITSIZE (resolved_type, i) != 0) new_bit_length += TYPE_FIELD_BITSIZE (resolved_type, i); else - new_bit_length += (TYPE_LENGTH (resolved_type->field (i).type ()) - * TARGET_CHAR_BIT); + { + struct type *real_type + = check_typedef (resolved_type->field (i).type ()); + + new_bit_length += (TYPE_LENGTH (real_type) * TARGET_CHAR_BIT); + } /* Normally, we would use the position and size of the last field to determine the size of the enclosing structure. But GCC seems diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index e0fece65a00..7ff7de2b526 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,15 @@ +2020-06-11 Keith Seitz + + PR gdb/21356 + * gdb.base/vla-datatypes.c (vla_factory): Add typedef for struct + vla_struct. + Add new struct vla_typedef and union vla_typedef_union and + corresponding instantiation objects. + Initialize new objects. + * gdb.base/vla-datatypes.exp: Add tests for vla_typedef_struct_object + and vla_typedef_union_object. + Fixup type for vla_struct_object. + 2020-06-11 Tom de Vries * lib/gdb.exp (with_override): New proc, factored out of ... diff --git a/gdb/testsuite/gdb.base/vla-datatypes.c b/gdb/testsuite/gdb.base/vla-datatypes.c index ecdcf4313c2..682319fbdeb 100644 --- a/gdb/testsuite/gdb.base/vla-datatypes.c +++ b/gdb/testsuite/gdb.base/vla-datatypes.c @@ -50,7 +50,10 @@ vla_factory (int n) { int something; int vla_field[n]; - } vla_struct_object; + }; + /* Define a typedef for a VLA structure. */ + typedef struct vla_struct vla_struct_typedef; + vla_struct_typedef vla_struct_object; struct inner_vla_struct { @@ -59,14 +62,33 @@ vla_factory (int n) int after; } inner_vla_struct_object; + /* Define a structure which uses a typedef for the VLA field + to make sure that GDB creates the proper type for this field, + preventing a possible assertion failure (see gdb/21356). */ + struct vla_struct_typedef_struct_member + { + int something; + vla_struct_typedef vla_object; + } vla_struct_typedef_struct_member_object; + union vla_union { int vla_field[n]; } vla_union_object; + /* Like vla_struct_typedef_struct_member but a union type. */ + union vla_struct_typedef_union_member + { + int something; + vla_struct_typedef vla_object; + } vla_struct_typedef_union_member_object; + vla_struct_object.something = n; inner_vla_struct_object.something = n; inner_vla_struct_object.after = n; + vla_struct_typedef_struct_member_object.something = n * 2; + vla_struct_typedef_struct_member_object.vla_object.something = n * 3; + vla_struct_typedef_union_member_object.vla_object.something = n + 1; for (i = 0; i < n; i++) { int_vla[i] = i*2; @@ -85,6 +107,10 @@ vla_factory (int n) vla_struct_object.vla_field[i] = i*2; vla_union_object.vla_field[i] = i*2; inner_vla_struct_object.vla_field[i] = i*2; + vla_struct_typedef_struct_member_object.vla_object.vla_field[i] + = i * 3; + vla_struct_typedef_union_member_object.vla_object.vla_field[i] + = i * 3 - 1; } size_t int_size = sizeof(int_vla); /* vlas_filled */ diff --git a/gdb/testsuite/gdb.base/vla-datatypes.exp b/gdb/testsuite/gdb.base/vla-datatypes.exp index fbc2c97936a..e8d84579fed 100644 --- a/gdb/testsuite/gdb.base/vla-datatypes.exp +++ b/gdb/testsuite/gdb.base/vla-datatypes.exp @@ -45,6 +45,10 @@ gdb_test "print vla_struct_object" \ "\\\{something = 5, vla_field = \\\{0, 2, 4, 6, 8\\\}\\\}" gdb_test "print vla_union_object" \ "\\\{vla_field = \\\{0, 2, 4, 6, 8\\\}\\\}" +gdb_test "print vla_struct_typedef_struct_member_object" \ + "\\\{something = 10, vla_object = \\\{something = 15, vla_field = \\\{0, 3, 6, 9, 12\\\}\\\}\\\}" +gdb_test "print vla_struct_typedef_union_member_object" \ + "\\\{something = 6, vla_object = \\\{something = 6, vla_field = \\\{-1, 2, 5, 8, 11\\\}\\\}\\\}" # Check whatis of VLA's. gdb_test "whatis int_vla" "type = int \\\[5\\\]" @@ -61,7 +65,7 @@ gdb_test "whatis unsigned_short_vla" \ gdb_test "whatis unsigned_char_vla" "type = unsigned char \\\[5\\\]" gdb_test "whatis foo_vla" "type = struct foo \\\[5\\\]" gdb_test "whatis bar_vla" "type = BAR \\\[5\\\]" -gdb_test "whatis vla_struct_object" "type = struct vla_struct" +gdb_test "whatis vla_struct_object" "type = vla_struct_typedef" gdb_test "whatis vla_union_object" "type = union vla_union" # Check ptype of VLA's. -- cgit v1.2.1