Verilator 4.016 2019-06-16 released

[wsnyder]

Verilator 4.016 2019-06-16 released

Notable:

• Add --quiet-exit. (verilator/verilator#1436) [Todd Strader]

Other:

• Error continuation lines no longer have %Error prefix.
• Support logical equivalence operator <->.
• Support VerilatedFstC set_time_unit. (verilator/verilator#1433) [Pieter Kapsenberg]
• Support deferred assertions. (verilator/verilator#1449) [Charles Eddleston]
• Mark infrequently called functions with GCC cold attribute.
• Fix sign-compare warning in verilated.cpp. (verilator/verilator#1437) [Sergey Kvachonok]
• Fix fault on $realtime with %t. (verilator/verilator#1443) [Julien Margetts]
• Fix $display with string without %s. (verilator/verilator#1441) [Denis Rystsov]
• Fix parameter function string returns. (verilator/verilator#1441) [Denis Rystsov]
• Fix invalid XML output due to special chars. (verilator/verilator#1444) [Kanad Kanhere]
• Fix performance when mulithreaded on 1 CPU. (verilator/verilator#1455) [Stefan Wallentowitz]
• Fix type and real parameter issues (verilator/verilator#1427) (verilator/verilator#1456) (verilator/verilator#1458) [Todd Strader]
• Fix build error on MinGW. (verilator/verilator#1460) [Richard Myers]
• Fix not reporting some duplicate signals. (verilator/verilator#1462) [Peter Gerst]
• Fix --savable invalid C++ on packed arrays. (verilator/verilator#1465) [Alex Chadwick]
• Fix constant function return of function var. (verilator/verilator#1467) [Roman Popov]