https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67258
Bug ID: 67258
Summary: "invalid vptr" false positive from ubsan for virtual
inheritance
Product: gcc
Version: 5.1.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: sanitizer
Assignee: unassigned at gcc dot gnu.org
Reporter: arvo at me dot com
CC: dodji at gcc dot gnu.org, dvyukov at gcc dot gnu.org,
jakub at gcc dot gnu.org, kcc at gcc dot gnu.org
Target Milestone: ---
Created attachment 36200
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=36200&action=edit
Minimal test program that triggers "invalid vptr" message from ubsan
Building the attached minimal test program, which should be free of undefined
behavior, with --sanitize=undefined and executing it yields:
ubsan-virtual.cxx:7:8: runtime error: member call on address 0x7fff43c04a20
which does not point to an object of type 'A'
0x7fff43c04a20: note: object has invalid vptr
00 00 00 00 40 18 40 00 00 00 00 00 18 18 40 00 00 00 00 00 20 4b c0 43 ff
7f 00 00 00 3c c4 4f
^~~~~~~~~~~~~~~~~~~~~~~
invalid vptr
