vhdl_input_version Synthesis Directive
A VHDL synthesis directive that specifies the VHDL language version for the design units in a VHDL Design File (.vhd) Definition. This directive overrides the default HDL version and any HDL version specified in the File Properties dialog box.
-- synthesis VHDL_INPUT_VERSION <language version>
To use the VHDL_INPUT_VERSION
directive, embed it in a VHDL comment at the point where you want
to start using that language version. This directive takes a single
string argument, the <language version>
of the VHDL language you wish to use, which can be either
VHDL_1987
,
VHDL_1993
, or
VHDL_2008
.
When the
Quartus® Prime software reads a VHDL_INPUT_VERSION
directive, it changes the current language version as specified
until the end of the file, or until it reaches the next
VHDL_INPUT_VERSION
directive.