PVS-Studio warning V521 for Quake3

void Q1_AllocMaxBSP(void)
{
  ...
  q1_allocatedbspmem +=
    Q1_MAX_MAP_CLIPNODES * sizeof(q1_dclipnode_t);
  ...
  q1_allocatedbspmem +=
    Q1_MAX_MAP_EDGES , sizeof(q1_dedge_t);          <<<---
  ...
  q1_allocatedbspmem +=
    Q1_MAX_MAP_MARKSURFACES * sizeof(unsigned short);
  ...
}

This suspicious code was found in Quake3 project by PVS-Studio static code analyzer.
Warning message is:
V521 Such expressions using the ',' operator are dangerous. Make sure the expression is correct. bspc l_bsp_q1.c 136

PVS-Studio is a static analyzer for detecting bugs in the source code of applications written in C, C++, C++11, C++/CX. Site: http://www.viva64.com/en/pvs-studio/