I tried to simulate cvfpu
(a floating-point unit written in SystemVerilog) with iverilog, but the compiler gave up every time when there was parameter int unsigned
in source code even if I added -g2005-sv
. Does it mean that int unsigned
is not supported by iverilog? And I'll also be appreciated that you can tell me how to simulate SystemVerilog codes, like cvfpu
, with iverilog (not vcs).
2 Answers
iverilog
does not support all SystemVerilog features.
I tried a trivial example on EDA Playground using the latest version of iverilog
which is available there, and it also generates a syntax error. It uses the -g2012
option to enable SystemVerilog features. The example compiles without errors with other simulators on that site.
If you want to continue to use iverilog
, you can try to contact the developers to see if a newer version is available.
Otherwise, you need to use a different simulator to run simulations with this syntax.

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It is worth mentioning that EDA Playground currently only has very old versions of iverilog
avaliable. The latest released version of iverilog
is V12 and their latest version is a preliminary (development) version of V10 from over 8 years ago. V12 was released half a year ago so a lot has changed since the V10 version they are providing.

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