Re: POSIX pthread counter (integer) overflow in valgrind drd_vc.c

> |drd: drd_vc.c:96 (vgDrd_vc_increment): Assertion 'oldcount < vc->vc[i].count' failed.
> My program was running a quite large volume of data (millions of records).

How many millions, and how long does the program run, both with an without drd?
It's quite possible to overflow the 'count', which is an unsigned 32-bit integer
(see drd/drd_vc.h.)  That's only 4300 times one million; I would not be surprised
by an overflow in one day of execution.

What version of drd?  (Run "valgrind --version".)
The drd addresses in the traceback are 0x38000000; current drd uses 0x58000000.
The other versions that you specified are somewhat old: gcc-4.8 (current is gcc-9.1)
and Linux 4.4.76 built 2017-07-14 (almost 2 years ago).