https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107818
Bug ID: 107818
Summary: Overflow of linemap breaks its chronological order
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: fxue at os dot amperecomputing.com
Target Milestone: ---
Large-size source codes might exceed representation space of linemap. When this
happens, UNKNOWN_LOCATION(0) would inserted to the end of linemap. And the
action breaks the order constraint on the map, which requires all logical
locations contained by it should remain chronologically-ordered, so that binary
search could be used.(Comments in linemap_ordinary_map_lookup).
In the function "linemap_add":
...
if (start_location >= LINE_MAP_MAX_LOCATION)
/* We ran out of line map space. */
start_location = 0;
line_map_ordinary *map
= linemap_check_ordinary (new_linemap (set, start_location));
^^^^^^^^^^^
UNKNOWN_LOCATION(0) is also added to linemap
map->reason = reason;
...
Afterwards, logical location to source line would be mis-translated.
pr86872 only partially fixed see-able ICE due to linemap overflow, but made a
this hidden issue.
