diff options
| -rw-r--r-- | gdb/ChangeLog | 6 | ||||
| -rw-r--r-- | gdb/ada-lang.c | 38 |
2 files changed, 42 insertions, 2 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 8872ab4..dd91159 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,5 +1,11 @@ 2010-11-22 Joel Brobecker <brobecker@adacore.com> + * ada-lang.c (ada_to_fixed_type): Expand function documentation. + Return the original type if the main type portions match rather + than when the type themselves match. + +2010-11-22 Joel Brobecker <brobecker@adacore.com> + * ada-lang.c (ada_template_to_fixed_record_type_1): For dynamic fields, check the field size against the maximum object size. diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c index 341db4a..4471481 100644 --- a/gdb/ada-lang.c +++ b/gdb/ada-lang.c @@ -7659,7 +7659,23 @@ ada_to_fixed_type_1 (struct type *type, const gdb_byte *valaddr, /* The same as ada_to_fixed_type_1, except that it preserves the type if it is a TYPE_CODE_TYPEDEF of a type that is already fixed. - ada_to_fixed_type_1 would return the type referenced by TYPE. */ + + The typedef layer needs be preserved in order to differentiate between + arrays and array pointers when both types are implemented using the same + fat pointer. In the array pointer case, the pointer is encoded as + a typedef of the pointer type. For instance, considering: + + type String_Access is access String; + S1 : String_Access := null; + + To the debugger, S1 is defined as a typedef of type String. But + to the user, it is a pointer. So if the user tries to print S1, + we should not dereference the array, but print the array address + instead. + + If we didn't preserve the typedef layer, we would lose the fact that + the type is to be presented as a pointer (needs de-reference before + being printed). And we would also use the source-level type name. */ struct type * ada_to_fixed_type (struct type *type, const gdb_byte *valaddr, @@ -7669,8 +7685,26 @@ ada_to_fixed_type (struct type *type, const gdb_byte *valaddr, struct type *fixed_type = ada_to_fixed_type_1 (type, valaddr, address, dval, check_tag); + /* If TYPE is a typedef and its target type is the same as the FIXED_TYPE, + then preserve the typedef layer. + + Implementation note: We can only check the main-type portion of + the TYPE and FIXED_TYPE, because eliminating the typedef layer + from TYPE now returns a type that has the same instance flags + as TYPE. For instance, if TYPE is a "typedef const", and its + target type is a "struct", then the typedef elimination will return + a "const" version of the target type. See check_typedef for more + details about how the typedef layer elimination is done. + + brobecker/2010-11-19: It seems to me that the only case where it is + useful to preserve the typedef layer is when dealing with fat pointers. + Perhaps, we could add a check for that and preserve the typedef layer + only in that situation. But this seems unecessary so far, probably + because we call check_typedef/ada_check_typedef pretty much everywhere. + */ if (TYPE_CODE (type) == TYPE_CODE_TYPEDEF - && TYPE_TARGET_TYPE (type) == fixed_type) + && (TYPE_MAIN_TYPE (TYPE_TARGET_TYPE (type)) + == TYPE_MAIN_TYPE (fixed_type))) return type; return fixed_type; |