gdb/dwarf: update comment of cutu_reader::cutu_reader (the DWO variant)
The comment on this constructor is really outdated. Update it to better
reflect the reality today.
I'd eventually like to change this cutu_reader constructor not to use
dwarf2_per_cu, because it seems like an abuse of dwarf2_per_cu just to
pass 3 values. But for now, just document the existing behavior.
Change-Id: Id96db020c361e64d9b0d2f25d51950b206658aa2
Approved-By: Tom Tromey <tom@tromey.com>
diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c
index bcfa254..b3ad50a 100644
--- a/gdb/dwarf2/read.c
+++ b/gdb/dwarf2/read.c
@@ -3167,21 +3167,17 @@ cutu_reader::release_cu ()
return std::move (m_new_cu);
}
-/* Read CU/TU THIS_CU but do not follow DW_AT_GNU_dwo_name (DW_AT_dwo_name)
- if present. DWO_FILE, if non-NULL, is the DWO file to read (the caller is
- assumed to have already done the lookup to find the DWO file).
+/* This constructor exists for the special case of reading many units in a row
+ from a given known DWO file.
- The caller is required to fill in THIS_CU->section, THIS_CU->offset, and
- THIS_CU->is_debug_types, but nothing else.
+ THIS_CU is a special dwarf2_per_cu to represent where to read the unit from,
+ in the DWO file. The caller is required to fill THIS_CU::SECTION,
+ THIS_CU::SECT_OFF, and THIS_CU::IS_DEBUG_TYPES. This constructor will fill
+ in the length. THIS_CU::SECTION must point to a section from the DWO file,
+ which is normally not the case for regular dwarf2_per_cu uses.
- We fill in THIS_CU->length.
-
- THIS_CU->cu is always freed when done.
- This is done in order to not leave THIS_CU->cu in a state where we have
- to care whether it refers to the "main" CU or the DWO CU.
-
- When parent_cu is passed, it is used to provide a default value for
- str_offsets_base and addr_base from the parent. */
+ PARENT_CU is the CU created when reading the skeleton unit, and is used to
+ provide a default value for str_offsets_base and addr_base. */
cutu_reader::cutu_reader (dwarf2_per_cu *this_cu,
dwarf2_per_objfile *per_objfile,
