https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87095
Bug ID: 87095
Summary: UndefinedBehaviorSanitizer vptr false positive with
virtual inheritance only with -fno-sanitize-recover
Product: gcc
Version: 8.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: sanitizer
Assignee: unassigned at gcc dot gnu.org
Reporter: vakevk at gmail 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, marxin at
gcc dot gnu.org
Target Milestone: ---
Created attachment 44591
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=44591&action=edit
main.cpp
Program does not run successfully when compiled with:
g++ -fsanitize=vptr -fno-sanitize-recover=vptr main.cpp
main.cpp:9:8: runtime error: member call on address 0x7ffd7987dc20 which does
not point to an object of type 'A'
0x7ffd7987dc20: note: object has invalid vptr
c1 55 00 00 00 00 00 00 00 00 00 00 00 b0 34 7e ca 6d 56 eb 20 dd 87 79 fd
7f 00 00 00 00 00 00
^~~~~~~~~~~~~~~~~~~~~~~
invalid vptr
Program runs successfully if -fno-sanitize-recover=vptr is not specified or
when compiled with clang++ (6.0.1-5) with the original options.
Even without knowing whether the error message is correct, there is bug here
because the message should be shown consistently regardless of the recovery
option.
g++ -v
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-pc-linux-gnu/8.2.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /build/gcc/src/gcc/configure --prefix=/usr --libdir=/usr/lib
--libexecdir=/usr/lib --mandir=/usr/share/man --infodir=/usr/share/info
--with-bugurl=https://bugs.archlinux.org/
--enable-languages=c,c++,ada,fortran,go,lto,objc,obj-c++ --enable-shared
--enable-threads=posix --enable-libmpx --with-system-zlib --with-isl
--enable-__cxa_atexit --disable-libunwind-exceptions --enable-clocale=gnu
--disable-libstdcxx-pch --disable-libssp --enable-gnu-unique-object
--enable-linker-build-id --enable-lto --enable-plugin
--enable-install-libiberty --with-linker-hash-style=gnu
--enable-gnu-indirect-function --enable-multilib --disable-werror
--enable-checking=release --enable-default-pie --enable-default-ssp
--enable-cet=auto
Thread model: posix
gcc version 8.2.0 (GCC)
