https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99307
--- Comment #10 from Richard Biener <rguenth at gcc dot gnu.org> --- Using valgrind on the testcase makes the problem easier to trigger. > valgrind ./class_assign_4.exe ==4208== Memcheck, a memory error detector ==4208== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al. ==4208== Using Valgrind-3.15.0 and LibVEX; rerun with -h for copyright info ==4208== Command: ./class_assign_4.exe ==4208== ==4208== Invalid write of size 8 ==4208== at 0x4C35863: memmove (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so) ==4208== by 0x4076A7: test_t1_ (in /home/rguenther/obj-gcc10-g/gcc/class_assign_4.exe) ==4208== by 0x409DEF: MAIN__ (in /home/rguenther/obj-gcc10-g/gcc/class_assign_4.exe) ==4208== by 0x409E2B: main (in /home/rguenther/obj-gcc10-g/gcc/class_assign_4.exe) ==4208== Address 0x5e47bd8 is 8 bytes inside a block of size 12 alloc'd ==4208== at 0x4C308BF: realloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so) ==4208== by 0x405C3C: test_t1_ (in /home/rguenther/obj-gcc10-g/gcc/class_assign_4.exe) ==4208== by 0x409DEF: MAIN__ (in /home/rguenther/obj-gcc10-g/gcc/class_assign_4.exe) ==4208== by 0x409E2B: main (in /home/rguenther/obj-gcc10-g/gcc/class_assign_4.exe) ==4208== ==4208== Invalid read of size 4 ==4208== at 0x405048: check_t1.2 (in /home/rguenther/obj-gcc10-g/gcc/class_assign_4.exe) ==4208== by 0x407822: test_t1_ (in /home/rguenther/obj-gcc10-g/gcc/class_assign_4.exe) ==4208== by 0x409DEF: MAIN__ (in /home/rguenther/obj-gcc10-g/gcc/class_assign_4.exe) ==4208== by 0x409E2B: main (in /home/rguenther/obj-gcc10-g/gcc/class_assign_4.exe) ==4208== Address 0x5e47be0 is 4 bytes after a block of size 12 alloc'd ==4208== at 0x4C308BF: realloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so) ==4208== by 0x405C3C: test_t1_ (in /home/rguenther/obj-gcc10-g/gcc/class_assign_4.exe) ==4208== by 0x409DEF: MAIN__ (in /home/rguenther/obj-gcc10-g/gcc/class_assign_4.exe) ...
