[Bug libstdc++/87787] [9 Regression][UBSAN] runtime error: null pointer passed as argument 2, which is declared to never be null

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87787

--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Author: redi
Date: Fri Nov  9 20:14:07 2018
New Revision: 265984

URL: https://gcc.gnu.org/viewcvs?rev=265984&root=gcc&view=rev
Log:
PR libstdc++/87787 fix UBsan error in std::vector

        PR libstdc++/87787
        * include/bits/stl_uninitialized.h (__relocate_a_1): Do not call
        memmove when there's nothing to copy (and pointers could be null).

Modified:
    trunk/libstdc++-v3/ChangeLog
    trunk/libstdc++-v3/include/bits/stl_uninitialized.h