diff options
| -rw-r--r-- | gdb/ChangeLog | 4 | ||||
| -rw-r--r-- | gdb/gdbtypes.c | 8 | ||||
| -rw-r--r-- | gdb/stabsread.c | 24 |
3 files changed, 27 insertions, 9 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 4e8de26..d758201 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,5 +1,9 @@ 2002-05-03 Jim Blandy <jimb@redhat.com> + * stabsread.c (cleanup_undefined_types): Use replace_type, not memcpy. + (read_type): Doc fix. + * gdbtypes.c (replace_type): Doc fix. + * stabsread.c (multiply_defined_struct): New complaint. (read_struct_type): If the type we were passed isn't empty, or incomplete, don't read the new struct type into it; complain, diff --git a/gdb/gdbtypes.c b/gdb/gdbtypes.c index fa01f36..9132c40 100644 --- a/gdb/gdbtypes.c +++ b/gdb/gdbtypes.c @@ -521,10 +521,10 @@ finish_cv_type (struct type *type) /* Replace the contents of ntype with the type *type. - This function should not be necessary, but is due to quirks in the stabs - reader. This should go away. It does not handle the replacement type - being cv-qualified; it could be easily fixed to, but it should go away, - remember? */ + When building recursive types, it is necessary to update a type's + definition after people already have references to it. The C + language's concept of an `incomplete type' is an acknowledgement of + this. */ void replace_type (struct type *ntype, struct type *type) { diff --git a/gdb/stabsread.c b/gdb/stabsread.c index 74a873e..7065b7b 100644 --- a/gdb/stabsread.c +++ b/gdb/stabsread.c @@ -2537,7 +2537,24 @@ again: the related problems with unnecessarily stubbed types; someone motivated should attempt to clean up the issue here as well. Once a type pointed to has been created it - should not be modified. */ + should not be modified. + + Well, it's not *absolutely* wrong. Constructing recursive + types (trees, linked lists) necessarily entails modifying + types after creating them. Constructing any loop structure + entails side effects. The Dwarf 2 reader does handle this + more gracefully (it never constructs more than once + instance of a type object, so it doesn't have to copy type + objects wholesale), but it still mutates type objects after + other folks have references to them. + + Keep in mind that this circularity/mutation issue shows up + at the source language level, too: C's "incomplete types", + for example. So the proper cleanup, I think, would be to + limit GDB's type smashing to match exactly those required + by the source language. So GDB could have a + "complete_this_type" function, but never create unnecessary + copies of a type otherwise. */ replace_type (type, xtype); TYPE_NAME (type) = NULL; TYPE_TAG_NAME (type) = NULL; @@ -5122,10 +5139,7 @@ cleanup_undefined_types (void) && (TYPE_CODE (SYMBOL_TYPE (sym)) == TYPE_CODE (*type)) && STREQ (SYMBOL_NAME (sym), typename)) - { - memcpy (*type, SYMBOL_TYPE (sym), - sizeof (struct type)); - } + replace_type (*type, SYMBOL_TYPE (sym)); } } } |