diff options
Diffstat (limited to 'gdb/ada-lang.c')
| -rw-r--r-- | gdb/ada-lang.c | 79 |
1 files changed, 74 insertions, 5 deletions
diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c index 7ea01c7..3a5b10f 100644 --- a/gdb/ada-lang.c +++ b/gdb/ada-lang.c @@ -228,8 +228,6 @@ static int ada_resolve_function (struct ada_symbol_info *, int, struct value **, int, const char *, struct type *); -static struct value *ada_coerce_to_simple_array (struct value *); - static int ada_is_direct_array_type (struct type *); static void ada_language_arch_info (struct gdbarch *, @@ -366,6 +364,41 @@ ada_inferior_exit (struct inferior *inf) /* Utilities */ +/* If TYPE is a TYPE_CODE_TYPEDEF type, return the target type after + all typedef layers have been pealed. Otherwise, return TYPE. + + Normally, we really expect a typedef type to only have 1 typedef layer. + In other words, we really expect the target type of a typedef type to be + a non-typedef type. This is particularly true for Ada units, because + the language does not have a typedef vs not-typedef distinction. + In that respect, the Ada compiler has been trying to eliminate as many + typedef definitions in the debugging information, since they generally + do not bring any extra information (we still use typedef under certain + circumstances related mostly to the GNAT encoding). + + Unfortunately, we have seen situations where the debugging information + generated by the compiler leads to such multiple typedef layers. For + instance, consider the following example with stabs: + + .stabs "pck__float_array___XUP:Tt(0,46)=s16P_ARRAY:(0,47)=[...]"[...] + .stabs "pck__float_array___XUP:t(0,36)=(0,46)",128,0,6,0 + + This is an error in the debugging information which causes type + pck__float_array___XUP to be defined twice, and the second time, + it is defined as a typedef of a typedef. + + This is on the fringe of legality as far as debugging information is + concerned, and certainly unexpected. But it is easy to handle these + situations correctly, so we can afford to be lenient in this case. */ + +static struct type * +ada_typedef_target_type (struct type *type) +{ + while (TYPE_CODE (type) == TYPE_CODE_TYPEDEF) + type = TYPE_TARGET_TYPE (type); + return type; +} + /* Given DECODED_NAME a string holding a symbol name in its decoded form (ie using the Ada dotted notation), returns its unqualified name. */ @@ -1354,6 +1387,9 @@ desc_base_type (struct type *type) if (type == NULL) return NULL; type = ada_check_typedef (type); + if (TYPE_CODE (type) == TYPE_CODE_TYPEDEF) + type = ada_typedef_target_type (type); + if (type != NULL && (TYPE_CODE (type) == TYPE_CODE_PTR || TYPE_CODE (type) == TYPE_CODE_REF)) @@ -1819,7 +1855,7 @@ ada_coerce_to_simple_array_ptr (struct value *arr) Otherwise, returns a standard GDB array describing ARR (which may be ARR itself if it already is in the proper form). */ -static struct value * +struct value * ada_coerce_to_simple_array (struct value *arr) { if (ada_is_array_descriptor_type (value_type (arr))) @@ -1893,10 +1929,17 @@ ada_is_unconstrained_packed_array_type (struct type *type) static long decode_packed_array_bitsize (struct type *type) { - char *raw_name = ada_type_name (ada_check_typedef (type)); + char *raw_name; char *tail; long bits; + /* Access to arrays implemented as fat pointers are encoded as a typedef + of the fat pointer type. We need the name of the fat pointer type + to do the decoding, so strip the typedef layer. */ + if (TYPE_CODE (type) == TYPE_CODE_TYPEDEF) + type = ada_typedef_target_type (type); + + raw_name = ada_type_name (ada_check_typedef (type)); if (!raw_name) raw_name = ada_type_name (desc_base_type (type)); @@ -1904,6 +1947,7 @@ decode_packed_array_bitsize (struct type *type) return 0; tail = strstr (raw_name, "___XP"); + gdb_assert (tail != NULL); if (sscanf (tail + sizeof ("___XP") - 1, "%ld", &bits) != 1) { @@ -7146,6 +7190,15 @@ ada_template_to_fixed_record_type_1 (struct type *type, { struct type *field_type = TYPE_FIELD_TYPE (type, f); + /* If our field is a typedef type (most likely a typedef of + a fat pointer, encoding an array access), then we need to + look at its target type to determine its characteristics. + In particular, we would miscompute the field size if we took + the size of the typedef (zero), instead of the size of + the target type. */ + if (TYPE_CODE (field_type) == TYPE_CODE_TYPEDEF) + field_type = ada_typedef_target_type (field_type); + TYPE_FIELD_TYPE (rtype, f) = field_type; TYPE_FIELD_NAME (rtype, f) = TYPE_FIELD_NAME (type, f); if (TYPE_FIELD_BITSIZE (type, f) > 0) @@ -7703,7 +7756,7 @@ ada_to_fixed_type (struct type *type, const gdb_byte *valaddr, because we call check_typedef/ada_check_typedef pretty much everywhere. */ if (TYPE_CODE (type) == TYPE_CODE_TYPEDEF - && (TYPE_MAIN_TYPE (TYPE_TARGET_TYPE (type)) + && (TYPE_MAIN_TYPE (ada_typedef_target_type (type)) == TYPE_MAIN_TYPE (fixed_type))) return type; @@ -7789,6 +7842,15 @@ ada_check_typedef (struct type *type) if (type == NULL) return NULL; + /* If our type is a typedef type of a fat pointer, then we're done. + We don't want to strip the TYPE_CODE_TYPDEF layer, because this is + what allows us to distinguish between fat pointers that represent + array types, and fat pointers that represent array access types + (in both cases, the compiler implements them as fat pointers). */ + if (TYPE_CODE (type) == TYPE_CODE_TYPEDEF + && is_thick_pntr (ada_typedef_target_type (type))) + return type; + CHECK_TYPEDEF (type); if (type == NULL || TYPE_CODE (type) != TYPE_CODE_ENUM || !TYPE_STUB (type) @@ -9282,6 +9344,13 @@ ada_evaluate_subexp (struct type *expect_type, struct expression *exp, argvec[0] = value_addr (argvec[0]); type = ada_check_typedef (value_type (argvec[0])); + + /* Ada allows us to implicitly dereference arrays when subscripting + them. So, if this is an typedef (encoding use for array access + types encoded as fat pointers), strip it now. */ + if (TYPE_CODE (type) == TYPE_CODE_TYPEDEF) + type = ada_typedef_target_type (type); + if (TYPE_CODE (type) == TYPE_CODE_PTR) { switch (TYPE_CODE (ada_check_typedef (TYPE_TARGET_TYPE (type)))) |