../packages/RandomPkg.vhd(92): Range 0 downto 1 is null

[vio123]

Hi all,

from RandomPkg.vhd  ref.: 2.1

* constant NULL_INTV : integer_vector (0 downto 1) := (others => 0);

Modelsim gives 

** Warning: [3] ../packages/RandomPkg.vhd(92): (vcom-1246) Range 0 downto 1 is null

NULL_INTV is used as init value, but why with this empty range ?

Bug, Feature ?

[Jim Lewis]

Actually technique.  Note it is not illegal in the language to do this.  The simulator just flags it because usually the code is wrong – in this case it is ok.  

It is used on functions normal and poisson to make the exclude vector optional.

CoveragePkg use same technique so expect a null vector warning there too.

Jim

[Author]

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